Adding upstream version 115.7.0esr.upstream/115.7.0esr

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 3971 insertions, 0 deletions

diff --git a/gfx/wr/webrender/src/batch.rs b/gfx/wr/webrender/src/batch.rs
new file mode 100644
index 0000000000..d2be9ed3b8
--- /dev/null
+++ b/gfx/wr/webrender/src/batch.rs
@@ -0,0 +1,3971 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+use api::{AlphaType, ClipMode, ImageRendering, ImageBufferKind};
+use api::{FontInstanceFlags, YuvColorSpace, YuvFormat, ColorDepth, ColorRange, PremultipliedColorF};
+use api::units::*;
+use crate::clip::{ClipNodeFlags, ClipNodeRange, ClipItemKind, ClipStore};
+use crate::command_buffer::{PrimitiveCommand, QuadFlags};
+use crate::spatial_tree::{SpatialTree, SpatialNodeIndex, CoordinateSystemId};
+use glyph_rasterizer::{GlyphFormat, SubpixelDirection};
+use crate::gpu_cache::{GpuBlockData, GpuCache, GpuCacheAddress};
+use crate::gpu_types::{BrushFlags, BrushInstance, PrimitiveHeaders, ZBufferId, ZBufferIdGenerator};
+use crate::gpu_types::{SplitCompositeInstance, QuadInstance};
+use crate::gpu_types::{PrimitiveInstanceData, RasterizationSpace, GlyphInstance};
+use crate::gpu_types::{PrimitiveHeader, PrimitiveHeaderIndex, TransformPaletteId, TransformPalette};
+use crate::gpu_types::{ImageBrushData, get_shader_opacity, BoxShadowData};
+use crate::gpu_types::{ClipMaskInstanceCommon, ClipMaskInstanceImage, ClipMaskInstanceRect, ClipMaskInstanceBoxShadow};
+use crate::internal_types::{FastHashMap, Swizzle, TextureSource, Filter};
+use crate::picture::{Picture3DContext, PictureCompositeMode, calculate_screen_uv};
+use crate::prim_store::{PrimitiveInstanceKind, ClipData};
+use crate::prim_store::{PrimitiveInstance, PrimitiveOpacity, SegmentInstanceIndex};
+use crate::prim_store::{BrushSegment, ClipMaskKind, ClipTaskIndex};
+use crate::prim_store::{VECS_PER_SEGMENT, PrimitiveInstanceIndex};
+use crate::render_target::RenderTargetContext;
+use crate::render_task_graph::{RenderTaskId, RenderTaskGraph};
+use crate::render_task::{RenderTaskAddress, RenderTaskKind};
+use crate::renderer::{BlendMode, ShaderColorMode};
+use crate::renderer::{MAX_VERTEX_TEXTURE_WIDTH, GpuBufferBuilder, GpuBufferAddress};
+use crate::resource_cache::{GlyphFetchResult, ImageProperties, ImageRequest};
+use crate::space::SpaceMapper;
+use crate::visibility::{PrimitiveVisibilityFlags, VisibilityState};
+use smallvec::SmallVec;
+use std::{f32, i32, usize};
+use crate::util::{project_rect, MaxRect, MatrixHelpers, TransformedRectKind, ScaleOffset};
+use crate::segment::EdgeAaSegmentMask;
+
+// Special sentinel value recognized by the shader. It is considered to be
+// a dummy task that doesn't mask out anything.
+const OPAQUE_TASK_ADDRESS: RenderTaskAddress = RenderTaskAddress(0x7fff);
+
+/// Used to signal there are no segments provided with this primitive.
+pub const INVALID_SEGMENT_INDEX: i32 = 0xffff;
+
+/// Size in device pixels for tiles that clip masks are drawn in.
+const CLIP_RECTANGLE_TILE_SIZE: i32 = 128;
+
+/// The minimum size of a clip mask before trying to draw in tiles.
+const CLIP_RECTANGLE_AREA_THRESHOLD: f32 = (CLIP_RECTANGLE_TILE_SIZE * CLIP_RECTANGLE_TILE_SIZE * 4) as f32;
+
+#[derive(Copy, Clone, PartialEq, Eq, Hash, Debug)]
+#[cfg_attr(feature = "capture", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
+pub enum BrushBatchKind {
+    Solid,
+    Image(ImageBufferKind),
+    Blend,
+    MixBlend {
+        task_id: RenderTaskId,
+        backdrop_id: RenderTaskId,
+    },
+    YuvImage(ImageBufferKind, YuvFormat, ColorDepth, YuvColorSpace, ColorRange),
+    LinearGradient,
+    Opacity,
+}
+
+#[derive(Copy, Clone, PartialEq, Eq, Hash, Debug)]
+#[cfg_attr(feature = "capture", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
+pub enum BatchKind {
+    SplitComposite,
+    TextRun(GlyphFormat),
+    Brush(BrushBatchKind),
+    Primitive,
+}
+
+/// Input textures for a primitive, without consideration of clip mask
+#[derive(Copy, Clone, Debug)]
+#[cfg_attr(feature = "capture", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
+pub struct TextureSet {
+    pub colors: [TextureSource; 3],
+}
+
+impl TextureSet {
+    const UNTEXTURED: TextureSet = TextureSet {
+        colors: [
+            TextureSource::Invalid,
+            TextureSource::Invalid,
+            TextureSource::Invalid,
+        ],
+    };
+
+    /// A textured primitive
+    fn prim_textured(
+        color: TextureSource,
+    ) -> Self {
+        TextureSet {
+            colors: [
+                color,
+                TextureSource::Invalid,
+                TextureSource::Invalid,
+            ],
+        }
+    }
+
+    fn is_compatible_with(&self, other: &TextureSet) -> bool {
+        self.colors[0].is_compatible(&other.colors[0]) &&
+        self.colors[1].is_compatible(&other.colors[1]) &&
+        self.colors[2].is_compatible(&other.colors[2])
+    }
+}
+
+impl TextureSource {
+    fn combine(&self, other: TextureSource) -> TextureSource {
+        if other == TextureSource::Invalid {
+            *self
+        } else {
+            other
+        }
+    }
+}
+
+/// Optional textures that can be used as a source in the shaders.
+/// Textures that are not used by the batch are equal to TextureId::invalid().
+#[derive(Copy, Clone, Debug)]
+#[cfg_attr(feature = "capture", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
+pub struct BatchTextures {
+    pub input: TextureSet,
+    pub clip_mask: TextureSource,
+}
+
+impl BatchTextures {
+    /// An empty batch textures (no binding slots set)
+    pub fn empty() -> BatchTextures {
+        BatchTextures {
+            input: TextureSet::UNTEXTURED,
+            clip_mask: TextureSource::Invalid,
+        }
+    }
+
+    /// A textured primitive with optional clip mask
+    pub fn prim_textured(
+        color: TextureSource,
+        clip_mask: TextureSource,
+    ) -> BatchTextures {
+        BatchTextures {
+            input: TextureSet::prim_textured(color),
+            clip_mask,
+        }
+    }
+
+    /// An untextured primitive with optional clip mask
+    pub fn prim_untextured(
+        clip_mask: TextureSource,
+    ) -> BatchTextures {
+        BatchTextures {
+            input: TextureSet::UNTEXTURED,
+            clip_mask,
+        }
+    }
+
+    /// A composite style effect with single input texture
+    pub fn composite_rgb(
+        texture: TextureSource,
+    ) -> BatchTextures {
+        BatchTextures {
+            input: TextureSet {
+                colors: [
+                    texture,
+                    TextureSource::Invalid,
+                    TextureSource::Invalid,
+                ],
+            },
+            clip_mask: TextureSource::Invalid,
+        }
+    }
+
+    /// A composite style effect with up to 3 input textures
+    pub fn composite_yuv(
+        color0: TextureSource,
+        color1: TextureSource,
+        color2: TextureSource,
+    ) -> BatchTextures {
+        BatchTextures {
+            input: TextureSet {
+                colors: [color0, color1, color2],
+            },
+            clip_mask: TextureSource::Invalid,
+        }
+    }
+
+    pub fn is_compatible_with(&self, other: &BatchTextures) -> bool {
+        if !self.clip_mask.is_compatible(&other.clip_mask) {
+            return false;
+        }
+
+        self.input.is_compatible_with(&other.input)
+    }
+
+    pub fn combine_textures(&self, other: BatchTextures) -> Option<BatchTextures> {
+        if !self.is_compatible_with(&other) {
+            return None;
+        }
+
+        let mut new_textures = BatchTextures::empty();
+
+        new_textures.clip_mask = self.clip_mask.combine(other.clip_mask);
+
+        for i in 0 .. 3 {
+            new_textures.input.colors[i] = self.input.colors[i].combine(other.input.colors[i]);
+        }
+
+        Some(new_textures)
+    }
+
+    fn merge(&mut self, other: &BatchTextures) {
+        self.clip_mask = self.clip_mask.combine(other.clip_mask);
+
+        for (s, o) in self.input.colors.iter_mut().zip(other.input.colors.iter()) {
+            *s = s.combine(*o);
+        }
+    }
+}
+
+#[derive(Copy, Clone, Debug)]
+#[cfg_attr(feature = "capture", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
+pub struct BatchKey {
+    pub kind: BatchKind,
+    pub blend_mode: BlendMode,
+    pub textures: BatchTextures,
+}
+
+impl BatchKey {
+    pub fn new(kind: BatchKind, blend_mode: BlendMode, textures: BatchTextures) -> Self {
+        BatchKey {
+            kind,
+            blend_mode,
+            textures,
+        }
+    }
+
+    pub fn is_compatible_with(&self, other: &BatchKey) -> bool {
+        self.kind == other.kind && self.blend_mode == other.blend_mode && self.textures.is_compatible_with(&other.textures)
+    }
+}
+
+pub struct BatchRects {
+    /// Union of all of the batch's item rects.
+    ///
+    /// Very often we can skip iterating over item rects by testing against
+    /// this one first.
+    batch: PictureRect,
+    /// When the batch rectangle above isn't a good enough approximation, we
+    /// store per item rects.
+    items: Option<Vec<PictureRect>>,
+}
+
+impl BatchRects {
+    fn new() -> Self {
+        BatchRects {
+            batch: PictureRect::zero(),
+            items: None,
+        }
+    }
+
+    #[inline]
+    fn add_rect(&mut self, rect: &PictureRect) {
+        let union = self.batch.union(rect);
+        // If we have already started storing per-item rects, continue doing so.
+        // Otherwise, check whether only storing the batch rect is a good enough
+        // approximation.
+        if let Some(items) = &mut self.items {
+            items.push(*rect);
+        } else if self.batch.area() + rect.area() < union.area() {
+            let mut items = Vec::with_capacity(16);
+            items.push(self.batch);
+            items.push(*rect);
+            self.items = Some(items);
+        }
+
+        self.batch = union;
+    }
+
+    #[inline]
+    fn intersects(&mut self, rect: &PictureRect) -> bool {
+        if !self.batch.intersects(rect) {
+            return false;
+        }
+
+        if let Some(items) = &self.items {
+            items.iter().any(|item| item.intersects(rect))
+        } else {
+            // If we don't have per-item rects it means the batch rect is a good
+            // enough approximation and we didn't bother storing per-rect items.
+            true
+        }
+    }
+}
+
+
+pub struct AlphaBatchList {
+    pub batches: Vec<PrimitiveBatch>,
+    pub batch_rects: Vec<BatchRects>,
+    current_batch_index: usize,
+    current_z_id: ZBufferId,
+    break_advanced_blend_batches: bool,
+}
+
+impl AlphaBatchList {
+    fn new(break_advanced_blend_batches: bool, preallocate: usize) -> Self {
+        AlphaBatchList {
+            batches: Vec::with_capacity(preallocate),
+            batch_rects: Vec::with_capacity(preallocate),
+            current_z_id: ZBufferId::invalid(),
+            current_batch_index: usize::MAX,
+            break_advanced_blend_batches,
+        }
+    }
+
+    /// Clear all current batches in this list. This is typically used
+    /// when a primitive is encountered that occludes all previous
+    /// content in this batch list.
+    fn clear(&mut self) {
+        self.current_batch_index = usize::MAX;
+        self.current_z_id = ZBufferId::invalid();
+        self.batches.clear();
+        self.batch_rects.clear();
+    }
+
+    pub fn set_params_and_get_batch(
+        &mut self,
+        key: BatchKey,
+        features: BatchFeatures,
+        // The bounding box of everything at this Z plane. We expect potentially
+        // multiple primitive segments coming with the same `z_id`.
+        z_bounding_rect: &PictureRect,
+        z_id: ZBufferId,
+    ) -> &mut Vec<PrimitiveInstanceData> {
+        if z_id != self.current_z_id ||
+           self.current_batch_index == usize::MAX ||
+           !self.batches[self.current_batch_index].key.is_compatible_with(&key)
+        {
+            let mut selected_batch_index = None;
+
+            match key.blend_mode {
+                BlendMode::SubpixelWithBgColor => {
+                    for (batch_index, batch) in self.batches.iter().enumerate().rev() {
+                        // Some subpixel batches are drawn in two passes. Because of this, we need
+                        // to check for overlaps with every batch (which is a bit different
+                        // than the normal batching below).
+                        if self.batch_rects[batch_index].intersects(z_bounding_rect) {
+                            break;
+                        }
+
+                        if batch.key.is_compatible_with(&key) {
+                            selected_batch_index = Some(batch_index);
+                            break;
+                        }
+                    }
+                }
+                BlendMode::Advanced(_) if self.break_advanced_blend_batches => {
+                    // don't try to find a batch
+                }
+                _ => {
+                    for (batch_index, batch) in self.batches.iter().enumerate().rev() {
+                        // For normal batches, we only need to check for overlaps for batches
+                        // other than the first batch we consider. If the first batch
+                        // is compatible, then we know there isn't any potential overlap
+                        // issues to worry about.
+                        if batch.key.is_compatible_with(&key) {
+                            selected_batch_index = Some(batch_index);
+                            break;
+                        }
+
+                        // check for intersections
+                        if self.batch_rects[batch_index].intersects(z_bounding_rect) {
+                            break;
+                        }
+                    }
+                }
+            }
+
+            if selected_batch_index.is_none() {
+                // Text runs tend to have a lot of instances per batch, causing a lot of reallocation
+                // churn as items are added one by one, so we give it a head start. Ideally we'd start
+                // with a larger number, closer to 1k but in some bad cases with lots of batch break
+                // we would be wasting a lot of memory.
+                // Generally it is safe to preallocate small-ish values for other batch kinds because
+                // the items are small and there are no zero-sized batches so there will always be
+                // at least one allocation.
+                let prealloc = match key.kind {
+                    BatchKind::TextRun(..) => 128,
+                    _ => 16,
+                };
+                let mut new_batch = PrimitiveBatch::new(key);
+                new_batch.instances.reserve(prealloc);
+                selected_batch_index = Some(self.batches.len());
+                self.batches.push(new_batch);
+                self.batch_rects.push(BatchRects::new());
+            }
+
+            self.current_batch_index = selected_batch_index.unwrap();
+            self.batch_rects[self.current_batch_index].add_rect(z_bounding_rect);
+            self.current_z_id = z_id;
+        }
+
+        let batch = &mut self.batches[self.current_batch_index];
+        batch.features |= features;
+        batch.key.textures.merge(&key.textures);
+
+        &mut batch.instances
+    }
+}
+
+pub struct OpaqueBatchList {
+    pub pixel_area_threshold_for_new_batch: f32,
+    pub batches: Vec<PrimitiveBatch>,
+    pub current_batch_index: usize,
+    lookback_count: usize,
+}
+
+impl OpaqueBatchList {
+    fn new(pixel_area_threshold_for_new_batch: f32, lookback_count: usize) -> Self {
+        OpaqueBatchList {
+            batches: Vec::new(),
+            pixel_area_threshold_for_new_batch,
+            current_batch_index: usize::MAX,
+            lookback_count,
+        }
+    }
+
+    /// Clear all current batches in this list. This is typically used
+    /// when a primitive is encountered that occludes all previous
+    /// content in this batch list.
+    fn clear(&mut self) {
+        self.current_batch_index = usize::MAX;
+        self.batches.clear();
+    }
+
+    pub fn set_params_and_get_batch(
+        &mut self,
+        key: BatchKey,
+        features: BatchFeatures,
+        // The bounding box of everything at the current Z, whatever it is. We expect potentially
+        // multiple primitive segments produced by a primitive, which we allow to check
+        // `current_batch_index` instead of iterating the batches.
+        z_bounding_rect: &PictureRect,
+    ) -> &mut Vec<PrimitiveInstanceData> {
+        if self.current_batch_index == usize::MAX ||
+           !self.batches[self.current_batch_index].key.is_compatible_with(&key) {
+            let mut selected_batch_index = None;
+            let item_area = z_bounding_rect.area();
+
+            // If the area of this primitive is larger than the given threshold,
+            // then it is large enough to warrant breaking a batch for. In this
+            // case we just see if it can be added to the existing batch or
+            // create a new one.
+            if item_area > self.pixel_area_threshold_for_new_batch {
+                if let Some(batch) = self.batches.last() {
+                    if batch.key.is_compatible_with(&key) {
+                        selected_batch_index = Some(self.batches.len() - 1);
+                    }
+                }
+            } else {
+                // Otherwise, look back through a reasonable number of batches.
+                for (batch_index, batch) in self.batches.iter().enumerate().rev().take(self.lookback_count) {
+                    if batch.key.is_compatible_with(&key) {
+                        selected_batch_index = Some(batch_index);
+                        break;
+                    }
+                }
+            }
+
+            if selected_batch_index.is_none() {
+                let new_batch = PrimitiveBatch::new(key);
+                selected_batch_index = Some(self.batches.len());
+                self.batches.push(new_batch);
+            }
+
+            self.current_batch_index = selected_batch_index.unwrap();
+        }
+
+        let batch = &mut self.batches[self.current_batch_index];
+        batch.features |= features;
+        batch.key.textures.merge(&key.textures);
+
+        &mut batch.instances
+    }
+
+    fn finalize(&mut self) {
+        // Reverse the instance arrays in the opaque batches
+        // to get maximum z-buffer efficiency by drawing
+        // front-to-back.
+        // TODO(gw): Maybe we can change the batch code to
+        //           build these in reverse and avoid having
+        //           to reverse the instance array here.
+        for batch in &mut self.batches {
+            batch.instances.reverse();
+        }
+    }
+}
+
+#[cfg_attr(feature = "capture", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
+pub struct PrimitiveBatch {
+    pub key: BatchKey,
+    pub instances: Vec<PrimitiveInstanceData>,
+    pub features: BatchFeatures,
+}
+
+bitflags! {
+    /// Features of the batch that, if not requested, may allow a fast-path.
+    ///
+    /// Rather than breaking batches when primitives request different features,
+    /// we always request the minimum amount of features to satisfy all items in
+    /// the batch.
+    /// The goal is to let the renderer be optionally select more specialized
+    /// versions of a shader if the batch doesn't require code certain code paths.
+    /// Not all shaders necessarily implement all of these features.
+    #[cfg_attr(feature = "capture", derive(Serialize))]
+    #[cfg_attr(feature = "replay", derive(Deserialize))]
+    pub struct BatchFeatures: u8 {
+        const ALPHA_PASS = 1 << 0;
+        const ANTIALIASING = 1 << 1;
+        const REPETITION = 1 << 2;
+        /// Indicates a primitive in this batch may use a clip mask.
+        const CLIP_MASK = 1 << 3;
+    }
+}
+
+impl PrimitiveBatch {
+    fn new(key: BatchKey) -> PrimitiveBatch {
+        PrimitiveBatch {
+            key,
+            instances: Vec::new(),
+            features: BatchFeatures::empty(),
+        }
+    }
+
+    fn merge(&mut self, other: PrimitiveBatch) {
+        self.instances.extend(other.instances);
+        self.features |= other.features;
+        self.key.textures.merge(&other.key.textures);
+    }
+}
+
+#[cfg_attr(feature = "capture", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
+pub struct AlphaBatchContainer {
+    pub opaque_batches: Vec<PrimitiveBatch>,
+    pub alpha_batches: Vec<PrimitiveBatch>,
+    /// The overall scissor rect for this render task, if one
+    /// is required.
+    pub task_scissor_rect: Option<DeviceIntRect>,
+    /// The rectangle of the owning render target that this
+    /// set of batches affects.
+    pub task_rect: DeviceIntRect,
+}
+
+impl AlphaBatchContainer {
+    pub fn new(
+        task_scissor_rect: Option<DeviceIntRect>,
+    ) -> AlphaBatchContainer {
+        AlphaBatchContainer {
+            opaque_batches: Vec::new(),
+            alpha_batches: Vec::new(),
+            task_scissor_rect,
+            task_rect: DeviceIntRect::zero(),
+        }
+    }
+
+    pub fn is_empty(&self) -> bool {
+        self.opaque_batches.is_empty() &&
+        self.alpha_batches.is_empty()
+    }
+
+    fn merge(&mut self, builder: AlphaBatchBuilder, task_rect: &DeviceIntRect) {
+        self.task_rect = self.task_rect.union(task_rect);
+
+        for other_batch in builder.opaque_batch_list.batches {
+            let batch_index = self.opaque_batches.iter().position(|batch| {
+                batch.key.is_compatible_with(&other_batch.key)
+            });
+
+            match batch_index {
+                Some(batch_index) => {
+                    self.opaque_batches[batch_index].merge(other_batch);
+                }
+                None => {
+                    self.opaque_batches.push(other_batch);
+                }
+            }
+        }
+
+        let mut min_batch_index = 0;
+
+        for other_batch in builder.alpha_batch_list.batches {
+            let batch_index = self.alpha_batches.iter().skip(min_batch_index).position(|batch| {
+                batch.key.is_compatible_with(&other_batch.key)
+            });
+
+            match batch_index {
+                Some(batch_index) => {
+                    let index = batch_index + min_batch_index;
+                    self.alpha_batches[index].merge(other_batch);
+                    min_batch_index = index;
+                }
+                None => {
+                    self.alpha_batches.push(other_batch);
+                    min_batch_index = self.alpha_batches.len();
+                }
+            }
+        }
+    }
+}
+
+/// Each segment can optionally specify a per-segment
+/// texture set and one user data field.
+#[derive(Debug, Copy, Clone)]
+struct SegmentInstanceData {
+    textures: TextureSet,
+    specific_resource_address: i32,
+}
+
+/// Encapsulates the logic of building batches for items that are blended.
+pub struct AlphaBatchBuilder {
+    pub alpha_batch_list: AlphaBatchList,
+    pub opaque_batch_list: OpaqueBatchList,
+    pub render_task_id: RenderTaskId,
+    render_task_address: RenderTaskAddress,
+}
+
+impl AlphaBatchBuilder {
+    pub fn new(
+        screen_size: DeviceIntSize,
+        break_advanced_blend_batches: bool,
+        lookback_count: usize,
+        render_task_id: RenderTaskId,
+        render_task_address: RenderTaskAddress,
+    ) -> Self {
+        // The threshold for creating a new batch is
+        // one quarter the screen size.
+        let batch_area_threshold = (screen_size.width * screen_size.height) as f32 / 4.0;
+
+        AlphaBatchBuilder {
+            alpha_batch_list: AlphaBatchList::new(break_advanced_blend_batches, 128),
+            opaque_batch_list: OpaqueBatchList::new(batch_area_threshold, lookback_count),
+            render_task_id,
+            render_task_address,
+        }
+    }
+
+    /// Clear all current batches in this builder. This is typically used
+    /// when a primitive is encountered that occludes all previous
+    /// content in this batch list.
+    fn clear(&mut self) {
+        self.alpha_batch_list.clear();
+        self.opaque_batch_list.clear();
+    }
+
+    pub fn build(
+        mut self,
+        batch_containers: &mut Vec<AlphaBatchContainer>,
+        merged_batches: &mut AlphaBatchContainer,
+        task_rect: DeviceIntRect,
+        task_scissor_rect: Option<DeviceIntRect>,
+    ) {
+        self.opaque_batch_list.finalize();
+
+        if task_scissor_rect.is_none() {
+            merged_batches.merge(self, &task_rect);
+        } else {
+            batch_containers.push(AlphaBatchContainer {
+                alpha_batches: self.alpha_batch_list.batches,
+                opaque_batches: self.opaque_batch_list.batches,
+                task_scissor_rect,
+                task_rect,
+            });
+        }
+    }
+
+    pub fn push_single_instance(
+        &mut self,
+        key: BatchKey,
+        features: BatchFeatures,
+        bounding_rect: &PictureRect,
+        z_id: ZBufferId,
+        instance: PrimitiveInstanceData,
+    ) {
+        self.set_params_and_get_batch(key, features, bounding_rect, z_id)
+            .push(instance);
+    }
+
+    pub fn set_params_and_get_batch(
+        &mut self,
+        key: BatchKey,
+        features: BatchFeatures,
+        bounding_rect: &PictureRect,
+        z_id: ZBufferId,
+    ) -> &mut Vec<PrimitiveInstanceData> {
+        match key.blend_mode {
+            BlendMode::None => {
+                self.opaque_batch_list
+                    .set_params_and_get_batch(key, features, bounding_rect)
+            }
+            BlendMode::Alpha |
+            BlendMode::PremultipliedAlpha |
+            BlendMode::PremultipliedDestOut |
+            BlendMode::SubpixelWithBgColor |
+            BlendMode::SubpixelDualSource |
+            BlendMode::Advanced(_) |
+            BlendMode::MultiplyDualSource |
+            BlendMode::Screen |
+            BlendMode::Exclusion |
+            BlendMode::PlusLighter => {
+                self.alpha_batch_list
+                    .set_params_and_get_batch(key, features, bounding_rect, z_id)
+            }
+        }
+    }
+}
+
+/// Supports (recursively) adding a list of primitives and pictures to an alpha batch
+/// builder. In future, it will support multiple dirty regions / slices, allowing the
+/// contents of a picture to be spliced into multiple batch builders.
+pub struct BatchBuilder {
+    /// A temporary buffer that is used during glyph fetching, stored here
+    /// to reduce memory allocations.
+    glyph_fetch_buffer: Vec<GlyphFetchResult>,
+
+    batcher: AlphaBatchBuilder,
+}
+
+impl BatchBuilder {
+    pub fn new(batcher: AlphaBatchBuilder) -> Self {
+        BatchBuilder {
+            glyph_fetch_buffer: Vec::new(),
+            batcher,
+        }
+    }
+
+    pub fn finalize(self) -> AlphaBatchBuilder {
+        self.batcher
+    }
+
+    fn add_brush_instance_to_batches(
+        &mut self,
+        batch_key: BatchKey,
+        features: BatchFeatures,
+        bounding_rect: &PictureRect,
+        z_id: ZBufferId,
+        segment_index: i32,
+        edge_flags: EdgeAaSegmentMask,
+        clip_task_address: RenderTaskAddress,
+        brush_flags: BrushFlags,
+        prim_header_index: PrimitiveHeaderIndex,
+        resource_address: i32,
+    ) {
+        let render_task_address = self.batcher.render_task_address;
+
+        let instance = BrushInstance {
+            segment_index,
+            edge_flags,
+            clip_task_address,
+            render_task_address,
+            brush_flags,
+            prim_header_index,
+            resource_address,
+        };
+
+        self.batcher.push_single_instance(
+            batch_key,
+            features,
+            bounding_rect,
+            z_id,
+            PrimitiveInstanceData::from(instance),
+        );
+    }
+
+    fn add_split_composite_instance_to_batches(
+        &mut self,
+        batch_key: BatchKey,
+        features: BatchFeatures,
+        bounding_rect: &PictureRect,
+        z_id: ZBufferId,
+        prim_header_index: PrimitiveHeaderIndex,
+        polygons_address: i32,
+    ) {
+        let render_task_address = self.batcher.render_task_address;
+
+        self.batcher.push_single_instance(
+            batch_key,
+            features,
+            bounding_rect,
+            z_id,
+            PrimitiveInstanceData::from(SplitCompositeInstance {
+                prim_header_index,
+                render_task_address,
+                polygons_address,
+                z: z_id,
+            }),
+        );
+    }
+
+    /// Clear all current batchers. This is typically used when a primitive
+    /// is encountered that occludes all previous content in this batch list.
+    fn clear_batches(&mut self) {
+        self.batcher.clear();
+    }
+
+    /// Add a quad primitive to the batch list, appllying edge AA and tiling
+    /// segments as required.
+    fn add_quad_to_batch(
+        &mut self,
+        prim_instance_index: PrimitiveInstanceIndex,
+        transform_id: TransformPaletteId,
+        gpu_buffer_address: GpuBufferAddress,
+        quad_flags: QuadFlags,
+        edge_flags: EdgeAaSegmentMask,
+        segment_index: u8,
+        task_id: RenderTaskId,
+        z_generator: &mut ZBufferIdGenerator,
+        prim_instances: &[PrimitiveInstance],
+        render_tasks: &RenderTaskGraph,
+    ) {
+        let prim_instance = &prim_instances[prim_instance_index.0 as usize];
+        let prim_info = &prim_instance.vis;
+        let bounding_rect = &prim_info.clip_chain.pic_coverage_rect;
+        let z_id = z_generator.next();
+
+        add_quad_to_batch(
+            self.batcher.render_task_address,
+            transform_id,
+            gpu_buffer_address,
+            quad_flags,
+            edge_flags,
+            segment_index,
+            task_id,
+            z_id,
+            render_tasks,
+            |key, instance| {
+                let batch = self.batcher.set_params_and_get_batch(
+                    key,
+                    BatchFeatures::empty(),
+                    bounding_rect,
+                    z_id,
+                );
+
+                batch.push(instance);
+            }
+        );
+    }
+
+    // Adds a primitive to a batch.
+    // It can recursively call itself in some situations, for
+    // example if it encounters a picture where the items
+    // in that picture are being drawn into the same target.
+    pub fn add_prim_to_batch(
+        &mut self,
+        cmd: &PrimitiveCommand,
+        prim_spatial_node_index: SpatialNodeIndex,
+        ctx: &RenderTargetContext,
+        gpu_cache: &mut GpuCache,
+        render_tasks: &RenderTaskGraph,
+        prim_headers: &mut PrimitiveHeaders,
+        transforms: &mut TransformPalette,
+        root_spatial_node_index: SpatialNodeIndex,
+        surface_spatial_node_index: SpatialNodeIndex,
+        z_generator: &mut ZBufferIdGenerator,
+        prim_instances: &[PrimitiveInstance],
+        _gpu_buffer_builder: &mut GpuBufferBuilder,
+        segments: &[RenderTaskId],
+    ) {
+        let (prim_instance_index, extra_prim_gpu_address) = match cmd {
+            PrimitiveCommand::Simple { prim_instance_index } => {
+                (prim_instance_index, None)
+            }
+            PrimitiveCommand::Complex { prim_instance_index, gpu_address } => {
+                (prim_instance_index, Some(gpu_address.as_int()))
+            }
+            PrimitiveCommand::Instance { prim_instance_index, gpu_buffer_address } => {
+                (prim_instance_index, Some(gpu_buffer_address.as_int()))
+            }
+            PrimitiveCommand::Quad { prim_instance_index, gpu_buffer_address, quad_flags, edge_flags, transform_id } => {
+                if segments.is_empty() {
+                    self.add_quad_to_batch(
+                        *prim_instance_index,
+                        *transform_id,
+                        *gpu_buffer_address,
+                        *quad_flags,
+                        *edge_flags,
+                        INVALID_SEGMENT_INDEX as u8,
+                        RenderTaskId::INVALID,
+                        z_generator,
+                        prim_instances,
+                        render_tasks,
+                    );
+                } else {
+                    for (i, task_id) in segments.iter().enumerate() {
+                        // TODO(gw): edge_flags should be per-segment, when used for more than composites
+                        debug_assert!(edge_flags.is_empty());
+
+                        self.add_quad_to_batch(
+                            *prim_instance_index,
+                            *transform_id,
+                            *gpu_buffer_address,
+                            *quad_flags,
+                            *edge_flags,
+                            i as u8,
+                            *task_id,
+                            z_generator,
+                            prim_instances,
+                            render_tasks,
+                        );
+                    }
+                }
+
+                return;
+            }
+        };
+
+        let prim_instance = &prim_instances[prim_instance_index.0 as usize];
+        let is_anti_aliased = ctx.data_stores.prim_has_anti_aliasing(prim_instance);
+
+        let brush_flags = if is_anti_aliased {
+            BrushFlags::FORCE_AA
+        } else {
+            BrushFlags::empty()
+        };
+
+        let vis_flags = match prim_instance.vis.state {
+            VisibilityState::Culled => {
+                return;
+            }
+            VisibilityState::PassThrough |
+            VisibilityState::Unset => {
+                panic!("bug: invalid visibility state");
+            }
+            VisibilityState::Visible { vis_flags, .. } => {
+                vis_flags
+            }
+        };
+
+        // If this primitive is a backdrop, that means that it is known to cover
+        // the entire picture cache background. In that case, the renderer will
+        // use the backdrop color as a clear color, and so we can drop this
+        // primitive and any prior primitives from the batch lists for this
+        // picture cache slice.
+        if vis_flags.contains(PrimitiveVisibilityFlags::IS_BACKDROP) {
+            self.clear_batches();
+            return;
+        }
+
+        let transform_id = transforms
+            .get_id(
+                prim_spatial_node_index,
+                root_spatial_node_index,
+                ctx.spatial_tree,
+            );
+
+        // TODO(gw): Calculating this for every primitive is a bit
+        //           wasteful. We should probably cache this in
+        //           the scroll node...
+        let transform_kind = transform_id.transform_kind();
+        let prim_info = &prim_instance.vis;
+        let bounding_rect = &prim_info.clip_chain.pic_coverage_rect;
+
+        let z_id = z_generator.next();
+
+        let prim_rect = ctx.data_stores.get_local_prim_rect(
+            prim_instance,
+            &ctx.prim_store.pictures,
+            ctx.surfaces,
+        );
+
+        let mut batch_features = BatchFeatures::empty();
+        if ctx.data_stores.prim_may_need_repetition(prim_instance) {
+            batch_features |= BatchFeatures::REPETITION;
+        }
+
+        if transform_kind != TransformedRectKind::AxisAligned || is_anti_aliased {
+            batch_features |= BatchFeatures::ANTIALIASING;
+        }
+
+        // Check if the primitive might require a clip mask.
+        if prim_info.clip_task_index != ClipTaskIndex::INVALID {
+            batch_features |= BatchFeatures::CLIP_MASK;
+        }
+
+        if !bounding_rect.is_empty() {
+            debug_assert_eq!(prim_info.clip_chain.pic_spatial_node_index, surface_spatial_node_index,
+                "The primitive's bounding box is specified in a different coordinate system from the current batch!");
+        }
+
+        match prim_instance.kind {
+            PrimitiveInstanceKind::Clear { data_handle } => {
+                let prim_data = &ctx.data_stores.prim[data_handle];
+                let prim_cache_address = gpu_cache.get_address(&prim_data.gpu_cache_handle);
+
+                let (clip_task_address, clip_mask_texture_id) = ctx.get_prim_clip_task_and_texture(
+                    prim_info.clip_task_index,
+                    render_tasks,
+                ).unwrap();
+
+                // TODO(gw): We can abstract some of the common code below into
+                //           helper methods, as we port more primitives to make
+                //           use of interning.
+
+                let prim_header = PrimitiveHeader {
+                    local_rect: prim_rect,
+                    local_clip_rect: prim_info.clip_chain.local_clip_rect,
+                    specific_prim_address: prim_cache_address,
+                    transform_id,
+                };
+
+                let prim_header_index = prim_headers.push(
+                    &prim_header,
+                    z_id,
+                    [get_shader_opacity(1.0), 0, 0, 0],
+                );
+
+                let batch_key = BatchKey {
+                    blend_mode: BlendMode::PremultipliedDestOut,
+                    kind: BatchKind::Brush(BrushBatchKind::Solid),
+                    textures: BatchTextures::prim_untextured(clip_mask_texture_id),
+                };
+
+                self.add_brush_instance_to_batches(
+                    batch_key,
+                    batch_features,
+                    bounding_rect,
+                    z_id,
+                    INVALID_SEGMENT_INDEX,
+                    prim_data.edge_aa_mask,
+                    clip_task_address,
+                    brush_flags | BrushFlags::PERSPECTIVE_INTERPOLATION,
+                    prim_header_index,
+                    0,
+                );
+            }
+            PrimitiveInstanceKind::NormalBorder { data_handle, ref render_task_ids, .. } => {
+                let prim_data = &ctx.data_stores.normal_border[data_handle];
+                let common_data = &prim_data.common;
+                let prim_cache_address = gpu_cache.get_address(&common_data.gpu_cache_handle);
+                let task_ids = &ctx.scratch.border_cache_handles[*render_task_ids];
+                let specified_blend_mode = BlendMode::PremultipliedAlpha;
+                let mut segment_data: SmallVec<[SegmentInstanceData; 8]> = SmallVec::new();
+
+                // Collect the segment instance data from each render
+                // task for each valid edge / corner of the border.
+
+                for task_id in task_ids {
+                    if let Some((uv_rect_address, texture)) = render_tasks.resolve_location(*task_id, gpu_cache) {
+                        segment_data.push(
+                            SegmentInstanceData {
+                                textures: TextureSet::prim_textured(texture),
+                                specific_resource_address: uv_rect_address.as_int(),
+                            }
+                        );
+                    }
+                }
+
+                // TODO: it would be less error-prone to get this info from the texture cache.
+                let image_buffer_kind = ImageBufferKind::Texture2D;
+
+                let blend_mode = if !common_data.opacity.is_opaque ||
+                    prim_info.clip_task_index != ClipTaskIndex::INVALID ||
+                    transform_kind == TransformedRectKind::Complex ||
+                    is_anti_aliased
+                {
+                    specified_blend_mode
+                } else {
+                    BlendMode::None
+                };
+
+                let prim_header = PrimitiveHeader {
+                    local_rect: prim_rect,
+                    local_clip_rect: prim_info.clip_chain.local_clip_rect,
+                    specific_prim_address: prim_cache_address,
+                    transform_id,
+                };
+
+                let batch_params = BrushBatchParameters::instanced(
+                    BrushBatchKind::Image(image_buffer_kind),
+                    ImageBrushData {
+                        color_mode: ShaderColorMode::Image,
+                        alpha_type: AlphaType::PremultipliedAlpha,
+                        raster_space: RasterizationSpace::Local,
+                        opacity: 1.0,
+                    }.encode(),
+                    segment_data,
+                );
+
+                let prim_header_index = prim_headers.push(
+                    &prim_header,
+                    z_id,
+                    batch_params.prim_user_data,
+                );
+
+                let border_data = &prim_data.kind;
+                self.add_segmented_prim_to_batch(
+                    Some(border_data.brush_segments.as_slice()),
+                    common_data.opacity,
+                    &batch_params,
+                    blend_mode,
+                    batch_features,
+                    brush_flags,
+                    common_data.edge_aa_mask,
+                    prim_header_index,
+                    bounding_rect,
+                    transform_kind,
+                    z_id,
+                    prim_info.clip_task_index,
+                    ctx,
+                    render_tasks,
+                );
+            }
+            PrimitiveInstanceKind::TextRun { data_handle, run_index, .. } => {
+                let run = &ctx.prim_store.text_runs[run_index];
+                let subpx_dir = run.used_font.get_subpx_dir();
+
+                // The GPU cache data is stored in the template and reused across
+                // frames and display lists.
+                let prim_data = &ctx.data_stores.text_run[data_handle];
+                let prim_cache_address = gpu_cache.get_address(&prim_data.gpu_cache_handle);
+
+                // The local prim rect is only informative for text primitives, as
+                // thus is not directly necessary for any drawing of the text run.
+                // However the glyph offsets are relative to the prim rect origin
+                // less the unsnapped reference frame offset. We also want the
+                // the snapped reference frame offset, because cannot recalculate
+                // it as it ignores the animated components for the transform. As
+                // such, we adjust the prim rect origin here, and replace the size
+                // with the unsnapped and snapped offsets respectively. This has
+                // the added bonus of avoiding quantization effects when storing
+                // floats in the extra header integers.
+                let prim_header = PrimitiveHeader {
+                    local_rect: LayoutRect {
+                        min: prim_rect.min - run.reference_frame_relative_offset,
+                        max: run.snapped_reference_frame_relative_offset.to_point(),
+                    },
+                    local_clip_rect: prim_info.clip_chain.local_clip_rect,
+                    specific_prim_address: prim_cache_address,
+                    transform_id,
+                };
+
+                let glyph_keys = &ctx.scratch.glyph_keys[run.glyph_keys_range];
+                let prim_header_index = prim_headers.push(
+                    &prim_header,
+                    z_id,
+                    [
+                        (run.raster_scale * 65535.0).round() as i32,
+                        0,
+                        0,
+                        0,
+                    ],
+                );
+                let base_instance = GlyphInstance::new(
+                    prim_header_index,
+                );
+                let batcher = &mut self.batcher;
+
+                let (clip_task_address, clip_mask_texture_id) = ctx.get_prim_clip_task_and_texture(
+                    prim_info.clip_task_index,
+                    render_tasks,
+                ).unwrap();
+
+                // The run.used_font.clone() is here instead of instead of inline in the `fetch_glyph`
+                // function call to work around a miscompilation.
+                // https://github.com/rust-lang/rust/issues/80111
+                let font = run.used_font.clone();
+                ctx.resource_cache.fetch_glyphs(
+                    font,
+                    &glyph_keys,
+                    &mut self.glyph_fetch_buffer,
+                    gpu_cache,
+                    |texture_id, glyph_format, glyphs| {
+                        debug_assert_ne!(texture_id, TextureSource::Invalid);
+
+                        let subpx_dir = subpx_dir.limit_by(glyph_format);
+
+                        let textures = BatchTextures::prim_textured(
+                            texture_id,
+                            clip_mask_texture_id,
+                        );
+
+                        let kind = BatchKind::TextRun(glyph_format);
+
+                        let (blend_mode, color_mode) = match glyph_format {
+                            GlyphFormat::Subpixel |
+                            GlyphFormat::TransformedSubpixel => {
+                                if run.used_font.bg_color.a != 0 {
+                                    (
+                                        BlendMode::SubpixelWithBgColor,
+                                        ShaderColorMode::FromRenderPassMode,
+                                    )
+                                } else {
+                                    debug_assert!(ctx.use_dual_source_blending);
+                                    (
+                                        BlendMode::SubpixelDualSource,
+                                        ShaderColorMode::SubpixelDualSource,
+                                    )
+                                }
+                            }
+                            GlyphFormat::Alpha |
+                            GlyphFormat::TransformedAlpha |
+                            GlyphFormat::Bitmap => {
+                                (
+                                    BlendMode::PremultipliedAlpha,
+                                    ShaderColorMode::Alpha,
+                                )
+                            }
+                            GlyphFormat::ColorBitmap => {
+                                (
+                                    BlendMode::PremultipliedAlpha,
+                                    if run.shadow {
+                                        // Ignore color and only sample alpha when shadowing.
+                                        ShaderColorMode::BitmapShadow
+                                    } else {
+                                        ShaderColorMode::ColorBitmap
+                                    },
+                                )
+                            }
+                        };
+
+                        // Calculate a tighter bounding rect of just the glyphs passed to this
+                        // callback from request_glyphs(), rather than using the bounds of the
+                        // entire text run. This improves batching when glyphs are fragmented
+                        // over multiple textures in the texture cache.
+                        // This code is taken from the ps_text_run shader.
+                        let tight_bounding_rect = {
+                            let snap_bias = match subpx_dir {
+                                SubpixelDirection::None => DeviceVector2D::new(0.5, 0.5),
+                                SubpixelDirection::Horizontal => DeviceVector2D::new(0.125, 0.5),
+                                SubpixelDirection::Vertical => DeviceVector2D::new(0.5, 0.125),
+                                SubpixelDirection::Mixed => DeviceVector2D::new(0.125, 0.125),
+                            };
+                            let text_offset = prim_header.local_rect.max.to_vector();
+
+                            let pic_bounding_rect = if run.used_font.flags.contains(FontInstanceFlags::TRANSFORM_GLYPHS) {
+                                let mut device_bounding_rect = DeviceRect::default();
+
+                                let glyph_transform = ctx.spatial_tree.get_relative_transform(
+                                    prim_spatial_node_index,
+                                    root_spatial_node_index,
+                                ).into_transform()
+                                    .with_destination::<WorldPixel>()
+                                    .then(&euclid::Transform3D::from_scale(ctx.global_device_pixel_scale));
+
+                                let glyph_translation = DeviceVector2D::new(glyph_transform.m41, glyph_transform.m42);
+
+                                let mut use_tight_bounding_rect = true;
+                                for glyph in glyphs {
+                                    let glyph_offset = prim_data.glyphs[glyph.index_in_text_run as usize].point + prim_header.local_rect.min.to_vector();
+
+                                    let transformed_offset = match glyph_transform.transform_point2d(glyph_offset) {
+                                        Some(transformed_offset) => transformed_offset,
+                                        None => {
+                                            use_tight_bounding_rect = false;
+                                            break;
+                                        }
+                                    };
+                                    let raster_glyph_offset = (transformed_offset + snap_bias).floor();
+                                    let raster_text_offset = (
+                                        glyph_transform.transform_vector2d(text_offset) +
+                                        glyph_translation +
+                                        DeviceVector2D::new(0.5, 0.5)
+                                    ).floor() - glyph_translation;
+
+                                    let device_glyph_rect = DeviceRect::from_origin_and_size(
+                                        glyph.offset + raster_glyph_offset.to_vector() + raster_text_offset,
+                                        glyph.size.to_f32(),
+                                    );
+
+                                    device_bounding_rect = device_bounding_rect.union(&device_glyph_rect);
+                                }
+
+                                if use_tight_bounding_rect {
+                                    let map_device_to_surface: SpaceMapper<PicturePixel, DevicePixel> = SpaceMapper::new_with_target(
+                                        root_spatial_node_index,
+                                        surface_spatial_node_index,
+                                        device_bounding_rect,
+                                        ctx.spatial_tree,
+                                    );
+
+                                    match map_device_to_surface.unmap(&device_bounding_rect) {
+                                        Some(r) => r.intersection(bounding_rect),
+                                        None => Some(*bounding_rect),
+                                    }
+                                } else {
+                                    Some(*bounding_rect)
+                                }
+                            } else {
+                                let mut local_bounding_rect = LayoutRect::default();
+
+                                let glyph_raster_scale = run.raster_scale * ctx.global_device_pixel_scale.get();
+
+                                for glyph in glyphs {
+                                    let glyph_offset = prim_data.glyphs[glyph.index_in_text_run as usize].point + prim_header.local_rect.min.to_vector();
+                                    let glyph_scale = LayoutToDeviceScale::new(glyph_raster_scale / glyph.scale);
+                                    let raster_glyph_offset = (glyph_offset * LayoutToDeviceScale::new(glyph_raster_scale) + snap_bias).floor() / glyph.scale;
+                                    let local_glyph_rect = LayoutRect::from_origin_and_size(
+                                        (glyph.offset + raster_glyph_offset.to_vector()) / glyph_scale + text_offset,
+                                        glyph.size.to_f32() / glyph_scale,
+                                    );
+
+                                    local_bounding_rect = local_bounding_rect.union(&local_glyph_rect);
+                                }
+
+                                let map_prim_to_surface: SpaceMapper<LayoutPixel, PicturePixel> = SpaceMapper::new_with_target(
+                                    surface_spatial_node_index,
+                                    prim_spatial_node_index,
+                                    *bounding_rect,
+                                    ctx.spatial_tree,
+                                );
+                                map_prim_to_surface.map(&local_bounding_rect)
+                            };
+
+                            let intersected = match pic_bounding_rect {
+                                // The text run may have been clipped, for example if part of it is offscreen.
+                                // So intersect our result with the original bounding rect.
+                                Some(rect) => rect.intersection(bounding_rect).unwrap_or_else(PictureRect::zero),
+                                // If space mapping went off the rails, fall back to the old behavior.
+                                //TODO: consider skipping the glyph run completely in this case.
+                                None => *bounding_rect,
+                            };
+
+                            intersected
+                        };
+
+                        let key = BatchKey::new(kind, blend_mode, textures);
+
+                        let render_task_address = batcher.render_task_address;
+                        let batch = batcher.alpha_batch_list.set_params_and_get_batch(
+                            key,
+                            batch_features,
+                            &tight_bounding_rect,
+                            z_id,
+                        );
+
+                        batch.reserve(glyphs.len());
+                        for glyph in glyphs {
+                            batch.push(base_instance.build(
+                                render_task_address,
+                                clip_task_address,
+                                subpx_dir,
+                                glyph.index_in_text_run,
+                                glyph.uv_rect_address,
+                                color_mode,
+                            ));
+                        }
+                    },
+                );
+            }
+            PrimitiveInstanceKind::LineDecoration { data_handle, ref render_task, .. } => {
+                // The GPU cache data is stored in the template and reused across
+                // frames and display lists.
+                let common_data = &ctx.data_stores.line_decoration[data_handle].common;
+                let prim_cache_address = gpu_cache.get_address(&common_data.gpu_cache_handle);
+
+                let (clip_task_address, clip_mask_texture_id) = ctx.get_prim_clip_task_and_texture(
+                    prim_info.clip_task_index,
+                    render_tasks,
+                ).unwrap();
+
+                let (batch_kind, textures, prim_user_data, specific_resource_address) = match render_task {
+                    Some(task_id) => {
+                        let (uv_rect_address, texture) = render_tasks.resolve_location(*task_id, gpu_cache).unwrap();
+                        let textures = BatchTextures::prim_textured(
+                            texture,
+                            clip_mask_texture_id,
+                        );
+                        (
+                            BrushBatchKind::Image(texture.image_buffer_kind()),
+                            textures,
+                            ImageBrushData {
+                                color_mode: ShaderColorMode::Image,
+                                alpha_type: AlphaType::PremultipliedAlpha,
+                                raster_space: RasterizationSpace::Local,
+                                opacity: 1.0,
+                            }.encode(),
+                            uv_rect_address.as_int(),
+                        )
+                    }
+                    None => {
+                        (
+                            BrushBatchKind::Solid,
+                            BatchTextures::prim_untextured(clip_mask_texture_id),
+                            [get_shader_opacity(1.0), 0, 0, 0],
+                            0,
+                        )
+                    }
+                };
+
+                // TODO(gw): We can abstract some of the common code below into
+                //           helper methods, as we port more primitives to make
+                //           use of interning.
+                let blend_mode = if !common_data.opacity.is_opaque ||
+                    prim_info.clip_task_index != ClipTaskIndex::INVALID ||
+                    transform_kind == TransformedRectKind::Complex ||
+                    is_anti_aliased
+                {
+                    BlendMode::PremultipliedAlpha
+                } else {
+                    BlendMode::None
+                };
+
+                let prim_header = PrimitiveHeader {
+                    local_rect: prim_rect,
+                    local_clip_rect: prim_info.clip_chain.local_clip_rect,
+                    specific_prim_address: prim_cache_address,
+                    transform_id,
+                };
+
+                let prim_header_index = prim_headers.push(
+                    &prim_header,
+                    z_id,
+                    prim_user_data,
+                );
+
+                let batch_key = BatchKey {
+                    blend_mode,
+                    kind: BatchKind::Brush(batch_kind),
+                    textures,
+                };
+
+                self.add_brush_instance_to_batches(
+                    batch_key,
+                    batch_features,
+                    bounding_rect,
+                    z_id,
+                    INVALID_SEGMENT_INDEX,
+                    common_data.edge_aa_mask,
+                    clip_task_address,
+                    brush_flags | BrushFlags::PERSPECTIVE_INTERPOLATION,
+                    prim_header_index,
+                    specific_resource_address,
+                );
+            }
+            PrimitiveInstanceKind::Picture { pic_index, segment_instance_index, .. } => {
+                let picture = &ctx.prim_store.pictures[pic_index.0];
+                let blend_mode = BlendMode::PremultipliedAlpha;
+                let prim_cache_address = gpu_cache.get_address(&ctx.globals.default_image_handle);
+
+                match picture.raster_config {
+                    Some(ref raster_config) => {
+                        // If the child picture was rendered in local space, we can safely
+                        // interpolate the UV coordinates with perspective correction.
+                        let brush_flags = brush_flags | BrushFlags::PERSPECTIVE_INTERPOLATION;
+
+                        let surface = &ctx.surfaces[raster_config.surface_index.0];
+                        let mut local_clip_rect = prim_info.clip_chain.local_clip_rect;
+
+                        // If we are drawing with snapping enabled, form a simple transform that just applies
+                        // the scale / translation from the raster transform. Otherwise, in edge cases where the
+                        // intermediate surface has a non-identity but axis-aligned transform (e.g. a 180 degree
+                        // rotation) it can be applied twice.
+                        let transform_id = if surface.surface_spatial_node_index == surface.raster_spatial_node_index {
+                            transform_id
+                        } else {
+                            let map_local_to_raster = SpaceMapper::new_with_target(
+                                root_spatial_node_index,
+                                surface.surface_spatial_node_index,
+                                LayoutRect::max_rect(),
+                                ctx.spatial_tree,
+                            );
+
+                            let raster_rect = map_local_to_raster
+                                .map(&prim_rect)
+                                .unwrap();
+
+                            let sx = (raster_rect.max.x - raster_rect.min.x) / (prim_rect.max.x - prim_rect.min.x);
+                            let sy = (raster_rect.max.y - raster_rect.min.y) / (prim_rect.max.y - prim_rect.min.y);
+
+                            let tx = raster_rect.min.x - sx * prim_rect.min.x;
+                            let ty = raster_rect.min.y - sy * prim_rect.min.y;
+
+                            let transform = ScaleOffset::new(sx, sy, tx, ty);
+
+                            let raster_clip_rect = map_local_to_raster
+                                .map(&prim_info.clip_chain.local_clip_rect)
+                                .unwrap();
+                            local_clip_rect = transform.unmap_rect(&raster_clip_rect);
+
+                            transforms.get_custom(transform.to_transform())
+                        };
+
+                        let prim_header = PrimitiveHeader {
+                            local_rect: prim_rect,
+                            local_clip_rect,
+                            specific_prim_address: prim_cache_address,
+                            transform_id,
+                        };
+
+                        let mut is_opaque = prim_info.clip_task_index == ClipTaskIndex::INVALID
+                            && surface.is_opaque
+                            && transform_kind == TransformedRectKind::AxisAligned
+                            && !is_anti_aliased;
+
+                        let pic_task_id = picture.primary_render_task_id.unwrap();
+
+                        match raster_config.composite_mode {
+                            PictureCompositeMode::TileCache { .. } => {
+                                // TODO(gw): For now, TileCache is still a composite mode, even though
+                                //           it will only exist as a top level primitive and never
+                                //           be encountered during batching. Consider making TileCache
+                                //           a standalone type, not a picture.
+                            }
+                            PictureCompositeMode::IntermediateSurface { .. } => {
+                                // TODO(gw): As an optimization, support making this a pass-through
+                                //           and/or drawing directly from here when possible
+                                //           (e.g. if not wrapped by filters / different spatial node).
+                            }
+                            PictureCompositeMode::Filter(ref filter) => {
+                                assert!(filter.is_visible());
+                                match filter {
+                                    Filter::Blur { .. } => {
+                                        let (clip_task_address, clip_mask_texture_id) = ctx.get_prim_clip_task_and_texture(
+                                            prim_info.clip_task_index,
+                                            render_tasks,
+                                        ).unwrap();
+
+                                        let kind = BatchKind::Brush(
+                                            BrushBatchKind::Image(ImageBufferKind::Texture2D)
+                                        );
+
+                                        let (uv_rect_address, texture) = render_tasks.resolve_location(
+                                            pic_task_id,
+                                            gpu_cache,
+                                        ).unwrap();
+                                        let textures = BatchTextures::prim_textured(
+                                            texture,
+                                            clip_mask_texture_id,
+                                        );
+
+                                        let key = BatchKey::new(
+                                            kind,
+                                            blend_mode,
+                                            textures,
+                                        );
+                                        let prim_header_index = prim_headers.push(
+                                            &prim_header,
+                                            z_id,
+                                            ImageBrushData {
+                                                color_mode: ShaderColorMode::Image,
+                                                alpha_type: AlphaType::PremultipliedAlpha,
+                                                raster_space: RasterizationSpace::Screen,
+                                                opacity: 1.0,
+                                            }.encode(),
+                                        );
+
+                                        self.add_brush_instance_to_batches(
+                                            key,
+                                            batch_features,
+                                            bounding_rect,
+                                            z_id,
+                                            INVALID_SEGMENT_INDEX,
+                                            EdgeAaSegmentMask::all(),
+                                            clip_task_address,
+                                            brush_flags,
+                                            prim_header_index,
+                                            uv_rect_address.as_int(),
+                                        );
+                                    }
+                                    Filter::DropShadows(shadows) => {
+                                        let (clip_task_address, clip_mask_texture_id) = ctx.get_prim_clip_task_and_texture(
+                                            prim_info.clip_task_index,
+                                            render_tasks,
+                                        ).unwrap();
+
+                                        // Draw an instance per shadow first, following by the content.
+
+                                        // The shadows and the content get drawn as a brush image.
+                                        let kind = BatchKind::Brush(
+                                            BrushBatchKind::Image(ImageBufferKind::Texture2D),
+                                        );
+
+                                        // Gets the saved render task ID of the content, which is
+                                        // deeper in the render task graph than the direct child.
+                                        let secondary_id = picture.secondary_render_task_id.expect("no secondary!?");
+                                        let content_source = {
+                                            let secondary_task = &render_tasks[secondary_id];
+                                            let texture_id = secondary_task.get_target_texture();
+                                            TextureSource::TextureCache(
+                                                texture_id,
+                                                Swizzle::default(),
+                                            )
+                                        };
+
+                                        // Retrieve the UV rect addresses for shadow/content.
+                                        let (shadow_uv_rect_address, shadow_texture) = render_tasks.resolve_location(
+                                            pic_task_id,
+                                            gpu_cache,
+                                        ).unwrap();
+                                        let shadow_textures = BatchTextures::prim_textured(
+                                            shadow_texture,
+                                            clip_mask_texture_id,
+                                        );
+
+                                        let content_uv_rect_address = render_tasks[secondary_id]
+                                            .get_texture_address(gpu_cache)
+                                            .as_int();
+
+                                        // Build BatchTextures for shadow/content
+                                        let content_textures = BatchTextures::prim_textured(
+                                            content_source,
+                                            clip_mask_texture_id,
+                                        );
+
+                                        // Build batch keys for shadow/content
+                                        let shadow_key = BatchKey::new(kind, blend_mode, shadow_textures);
+                                        let content_key = BatchKey::new(kind, blend_mode, content_textures);
+
+                                        for (shadow, shadow_gpu_data) in shadows.iter().zip(picture.extra_gpu_data_handles.iter()) {
+                                            // Get the GPU cache address of the extra data handle.
+                                            let shadow_prim_address = gpu_cache.get_address(shadow_gpu_data);
+
+                                            let shadow_rect = prim_header.local_rect.translate(shadow.offset);
+
+                                            let shadow_prim_header = PrimitiveHeader {
+                                                local_rect: shadow_rect,
+                                                specific_prim_address: shadow_prim_address,
+                                                ..prim_header
+                                            };
+
+                                            let shadow_prim_header_index = prim_headers.push(
+                                                &shadow_prim_header,
+                                                z_id,
+                                                ImageBrushData {
+                                                    color_mode: ShaderColorMode::Alpha,
+                                                    alpha_type: AlphaType::PremultipliedAlpha,
+                                                    raster_space: RasterizationSpace::Screen,
+                                                    opacity: 1.0,
+                                                }.encode(),
+                                            );
+
+                                            self.add_brush_instance_to_batches(
+                                                shadow_key,
+                                                batch_features,
+                                                bounding_rect,
+                                                z_id,
+                                                INVALID_SEGMENT_INDEX,
+                                                EdgeAaSegmentMask::all(),
+                                                clip_task_address,
+                                                brush_flags,
+                                                shadow_prim_header_index,
+                                                shadow_uv_rect_address.as_int(),
+                                            );
+                                        }
+                                        let z_id_content = z_generator.next();
+
+                                        let content_prim_header_index = prim_headers.push(
+                                            &prim_header,
+                                            z_id_content,
+                                            ImageBrushData {
+                                                color_mode: ShaderColorMode::Image,
+                                                alpha_type: AlphaType::PremultipliedAlpha,
+                                                raster_space: RasterizationSpace::Screen,
+                                                opacity: 1.0,
+                                            }.encode(),
+                                        );
+
+                                        self.add_brush_instance_to_batches(
+                                            content_key,
+                                            batch_features,
+                                            bounding_rect,
+                                            z_id_content,
+                                            INVALID_SEGMENT_INDEX,
+                                            EdgeAaSegmentMask::all(),
+                                            clip_task_address,
+                                            brush_flags,
+                                            content_prim_header_index,
+                                            content_uv_rect_address,
+                                        );
+                                    }
+                                    Filter::Opacity(_, amount) => {
+                                        let (clip_task_address, clip_mask_texture_id) = ctx.get_prim_clip_task_and_texture(
+                                            prim_info.clip_task_index,
+                                            render_tasks,
+                                        ).unwrap();
+
+                                        let amount = (amount * 65536.0) as i32;
+
+                                        let (uv_rect_address, texture) = render_tasks.resolve_location(
+                                            pic_task_id,
+                                            gpu_cache,
+                                        ).unwrap();
+                                        let textures = BatchTextures::prim_textured(
+                                            texture,
+                                            clip_mask_texture_id,
+                                        );
+
+
+                                        let key = BatchKey::new(
+                                            BatchKind::Brush(BrushBatchKind::Opacity),
+                                            BlendMode::PremultipliedAlpha,
+                                            textures,
+                                        );
+
+                                        let prim_header_index = prim_headers.push(&prim_header, z_id, [
+                                            uv_rect_address.as_int(),
+                                            amount,
+                                            0,
+                                            0,
+                                        ]);
+
+                                        self.add_brush_instance_to_batches(
+                                            key,
+                                            batch_features,
+                                            bounding_rect,
+                                            z_id,
+                                            INVALID_SEGMENT_INDEX,
+                                            EdgeAaSegmentMask::all(),
+                                            clip_task_address,
+                                            brush_flags,
+                                            prim_header_index,
+                                            0,
+                                        );
+                                    }
+                                    _ => {
+                                        let (clip_task_address, clip_mask_texture_id) = ctx.get_prim_clip_task_and_texture(
+                                            prim_info.clip_task_index,
+                                            render_tasks,
+                                        ).unwrap();
+
+                                        // Must be kept in sync with brush_blend.glsl
+                                        let filter_mode = filter.as_int();
+
+                                        let user_data = match filter {
+                                            Filter::Identity => 0x10000i32, // matches `Contrast(1)`
+                                            Filter::Contrast(amount) |
+                                            Filter::Grayscale(amount) |
+                                            Filter::Invert(amount) |
+                                            Filter::Saturate(amount) |
+                                            Filter::Sepia(amount) |
+                                            Filter::Brightness(amount) => {
+                                                (amount * 65536.0) as i32
+                                            }
+                                            Filter::SrgbToLinear | Filter::LinearToSrgb => 0,
+                                            Filter::HueRotate(angle) => {
+                                                (0.01745329251 * angle * 65536.0) as i32
+                                            }
+                                            Filter::ColorMatrix(_) => {
+                                                picture.extra_gpu_data_handles[0].as_int(gpu_cache)
+                                            }
+                                            Filter::Flood(_) => {
+                                                picture.extra_gpu_data_handles[0].as_int(gpu_cache)
+                                            }
+
+                                            // These filters are handled via different paths.
+                                            Filter::ComponentTransfer |
+                                            Filter::Blur { .. } |
+                                            Filter::DropShadows(..) |
+                                            Filter::Opacity(..) => unreachable!(),
+                                        };
+
+                                        // Other filters that may introduce opacity are handled via different
+                                        // paths.
+                                        if let Filter::ColorMatrix(..) = filter {
+                                            is_opaque = false;
+                                        }
+
+                                        let (uv_rect_address, texture) = render_tasks.resolve_location(
+                                            pic_task_id,
+                                            gpu_cache,
+                                        ).unwrap();
+                                        let textures = BatchTextures::prim_textured(
+                                            texture,
+                                            clip_mask_texture_id,
+                                        );
+
+                                        let blend_mode = if is_opaque {
+                                            BlendMode::None
+                                        } else {
+                                            BlendMode::PremultipliedAlpha
+                                        };
+
+                                        let key = BatchKey::new(
+                                            BatchKind::Brush(BrushBatchKind::Blend),
+                                            blend_mode,
+                                            textures,
+                                        );
+
+                                        let prim_header_index = prim_headers.push(&prim_header, z_id, [
+                                            uv_rect_address.as_int(),
+                                            filter_mode,
+                                            user_data,
+                                            0,
+                                        ]);
+
+                                        self.add_brush_instance_to_batches(
+                                            key,
+                                            batch_features,
+                                            bounding_rect,
+                                            z_id,
+                                            INVALID_SEGMENT_INDEX,
+                                            EdgeAaSegmentMask::all(),
+                                            clip_task_address,
+                                            brush_flags,
+                                            prim_header_index,
+                                            0,
+                                        );
+                                    }
+                                }
+                            }
+                            PictureCompositeMode::ComponentTransferFilter(handle) => {
+                                // This is basically the same as the general filter case above
+                                // except we store a little more data in the filter mode and
+                                // a gpu cache handle in the user data.
+                                let filter_data = &ctx.data_stores.filter_data[handle];
+                                let filter_mode : i32 = Filter::ComponentTransfer.as_int() |
+                                    ((filter_data.data.r_func.to_int() << 28 |
+                                      filter_data.data.g_func.to_int() << 24 |
+                                      filter_data.data.b_func.to_int() << 20 |
+                                      filter_data.data.a_func.to_int() << 16) as i32);
+
+                                let user_data = filter_data.gpu_cache_handle.as_int(gpu_cache);
+
+                                let (clip_task_address, clip_mask_texture_id) = ctx.get_prim_clip_task_and_texture(
+                                    prim_info.clip_task_index,
+                                    render_tasks,
+                                ).unwrap();
+
+                                let (uv_rect_address, texture) = render_tasks.resolve_location(
+                                    pic_task_id,
+                                    gpu_cache,
+                                ).unwrap();
+                                let textures = BatchTextures::prim_textured(
+                                    texture,
+                                    clip_mask_texture_id,
+                                );
+
+                                let key = BatchKey::new(
+                                    BatchKind::Brush(BrushBatchKind::Blend),
+                                    BlendMode::PremultipliedAlpha,
+                                    textures,
+                                );
+
+                                let prim_header_index = prim_headers.push(&prim_header, z_id, [
+                                    uv_rect_address.as_int(),
+                                    filter_mode,
+                                    user_data,
+                                    0,
+                                ]);
+
+                                self.add_brush_instance_to_batches(
+                                    key,
+                                    batch_features,
+                                    bounding_rect,
+                                    z_id,
+                                    INVALID_SEGMENT_INDEX,
+                                    EdgeAaSegmentMask::all(),
+                                    clip_task_address,
+                                    brush_flags,
+                                    prim_header_index,
+                                    0,
+                                );
+                            }
+                            PictureCompositeMode::MixBlend(mode) if BlendMode::from_mix_blend_mode(
+                                mode,
+                                ctx.use_advanced_blending,
+                                !ctx.break_advanced_blend_batches,
+                                ctx.use_dual_source_blending,
+                            ).is_some() => {
+                                let (clip_task_address, clip_mask_texture_id) = ctx.get_prim_clip_task_and_texture(
+                                    prim_info.clip_task_index,
+                                    render_tasks,
+                                ).unwrap();
+
+                                let (uv_rect_address, texture) = render_tasks.resolve_location(
+                                    pic_task_id,
+                                    gpu_cache,
+                                ).unwrap();
+                                let textures = BatchTextures::prim_textured(
+                                    texture,
+                                    clip_mask_texture_id,
+                                );
+
+
+                                let key = BatchKey::new(
+                                    BatchKind::Brush(
+                                        BrushBatchKind::Image(ImageBufferKind::Texture2D),
+                                    ),
+                                    BlendMode::from_mix_blend_mode(
+                                        mode,
+                                        ctx.use_advanced_blending,
+                                        !ctx.break_advanced_blend_batches,
+                                        ctx.use_dual_source_blending,
+                                    ).unwrap(),
+                                    textures,
+                                );
+                                let prim_header_index = prim_headers.push(
+                                    &prim_header,
+                                    z_id,
+                                    ImageBrushData {
+                                        color_mode: match key.blend_mode {
+                                            BlendMode::MultiplyDualSource => ShaderColorMode::MultiplyDualSource,
+                                            _ => ShaderColorMode::Image,
+                                        },
+                                        alpha_type: AlphaType::PremultipliedAlpha,
+                                        raster_space: RasterizationSpace::Screen,
+                                        opacity: 1.0,
+                                    }.encode(),
+                                );
+
+                                self.add_brush_instance_to_batches(
+                                    key,
+                                    batch_features,
+                                    bounding_rect,
+                                    z_id,
+                                    INVALID_SEGMENT_INDEX,
+                                    EdgeAaSegmentMask::all(),
+                                    clip_task_address,
+                                    brush_flags,
+                                    prim_header_index,
+                                    uv_rect_address.as_int(),
+                                );
+                            }
+                            PictureCompositeMode::MixBlend(mode) => {
+                                let (clip_task_address, clip_mask_texture_id) = ctx.get_prim_clip_task_and_texture(
+                                    prim_info.clip_task_index,
+                                    render_tasks,
+                                ).unwrap();
+                                let backdrop_id = picture.secondary_render_task_id.expect("no backdrop!?");
+
+                                let color0 = render_tasks[backdrop_id].get_target_texture();
+                                let color1 = render_tasks[pic_task_id].get_target_texture();
+
+                                // Create a separate brush instance for each batcher. For most cases,
+                                // there is only one batcher. However, in the case of drawing onto
+                                // a picture cache, there is one batcher per tile. Although not
+                                // currently used, the implementation of mix-blend-mode now supports
+                                // doing partial readbacks per-tile. In future, this will be enabled
+                                // and allow mix-blends to operate on picture cache surfaces without
+                                // a separate isolated intermediate surface.
+
+                                let render_task_address = self.batcher.render_task_address;
+
+                                let batch_key = BatchKey::new(
+                                    BatchKind::Brush(
+                                        BrushBatchKind::MixBlend {
+                                            task_id: self.batcher.render_task_id,
+                                            backdrop_id,
+                                        },
+                                    ),
+                                    BlendMode::PremultipliedAlpha,
+                                    BatchTextures {
+                                        input: TextureSet {
+                                            colors: [
+                                                TextureSource::TextureCache(
+                                                    color0,
+                                                    Swizzle::default(),
+                                                ),
+                                                TextureSource::TextureCache(
+                                                    color1,
+                                                    Swizzle::default(),
+                                                ),
+                                                TextureSource::Invalid,
+                                            ],
+                                        },
+                                        clip_mask: clip_mask_texture_id,
+                                    },
+                                );
+                                let src_uv_address = render_tasks[pic_task_id].get_texture_address(gpu_cache);
+                                let readback_uv_address = render_tasks[backdrop_id].get_texture_address(gpu_cache);
+                                let prim_header_index = prim_headers.push(&prim_header, z_id, [
+                                    mode as u32 as i32,
+                                    readback_uv_address.as_int(),
+                                    src_uv_address.as_int(),
+                                    0,
+                                ]);
+
+                                let instance = BrushInstance {
+                                    segment_index: INVALID_SEGMENT_INDEX,
+                                    edge_flags: EdgeAaSegmentMask::all(),
+                                    clip_task_address,
+                                    render_task_address,
+                                    brush_flags,
+                                    prim_header_index,
+                                    resource_address: 0,
+                                };
+
+                                self.batcher.push_single_instance(
+                                    batch_key,
+                                    batch_features,
+                                    bounding_rect,
+                                    z_id,
+                                    PrimitiveInstanceData::from(instance),
+                                );
+                            }
+                            PictureCompositeMode::Blit(_) => {
+                                match picture.context_3d {
+                                    Picture3DContext::In { root_data: Some(_), .. } => {
+                                        unreachable!("bug: should not have a raster_config");
+                                    }
+                                    Picture3DContext::In { root_data: None, .. } => {
+                                        // TODO(gw): Store this inside the split picture so that we
+                                        //           don't need to pass in extra_prim_gpu_address for
+                                        //           every prim instance.
+                                        // TODO(gw): Ideally we'd skip adding 3d child prims to batches
+                                        //           without gpu cache address but it's currently
+                                        //           used by the prepare pass. Refactor this!
+                                        let extra_prim_gpu_address = match extra_prim_gpu_address {
+                                            Some(prim_address) => prim_address,
+                                            None => return,
+                                        };
+
+                                        // Get clip task, if set, for the picture primitive.
+                                        let (child_clip_task_address, clip_mask_texture_id) = ctx.get_prim_clip_task_and_texture(
+                                            prim_info.clip_task_index,
+                                            render_tasks,
+                                        ).unwrap();
+
+                                        let prim_header = PrimitiveHeader {
+                                            local_rect: prim_rect,
+                                            local_clip_rect: prim_info.clip_chain.local_clip_rect,
+                                            specific_prim_address: GpuCacheAddress::INVALID,
+                                            transform_id: transforms
+                                                .get_id(
+                                                    prim_spatial_node_index,
+                                                    root_spatial_node_index,
+                                                    ctx.spatial_tree,
+                                                ),
+                                        };
+
+                                        let child_pic_task_id = picture
+                                            .primary_render_task_id
+                                            .unwrap();
+
+                                        let (uv_rect_address, texture) = render_tasks.resolve_location(
+                                            child_pic_task_id,
+                                            gpu_cache,
+                                        ).unwrap();
+                                        let textures = BatchTextures::prim_textured(
+                                            texture,
+                                            clip_mask_texture_id,
+                                        );
+
+                                        // Need a new z-id for each child preserve-3d context added
+                                        // by this inner loop.
+                                        let z_id = z_generator.next();
+
+                                        let prim_header_index = prim_headers.push(&prim_header, z_id, [
+                                            uv_rect_address.as_int(),
+                                            BrushFlags::PERSPECTIVE_INTERPOLATION.bits() as i32,
+                                            0,
+                                            child_clip_task_address.0 as i32,
+                                        ]);
+
+                                        let key = BatchKey::new(
+                                            BatchKind::SplitComposite,
+                                            BlendMode::PremultipliedAlpha,
+                                            textures,
+                                        );
+
+                                        self.add_split_composite_instance_to_batches(
+                                            key,
+                                            BatchFeatures::CLIP_MASK,
+                                            &prim_info.clip_chain.pic_coverage_rect,
+                                            z_id,
+                                            prim_header_index,
+                                            extra_prim_gpu_address,
+                                        );
+                                    }
+                                    Picture3DContext::Out { .. } => {
+                                        let uv_rect_address = render_tasks[pic_task_id]
+                                            .get_texture_address(gpu_cache)
+                                            .as_int();
+                                        let cache_render_task = &render_tasks[pic_task_id];
+                                        let texture_id = cache_render_task.get_target_texture();
+                                        let textures = TextureSet {
+                                            colors: [
+                                                TextureSource::TextureCache(
+                                                    texture_id,
+                                                    Swizzle::default(),
+                                                ),
+                                                TextureSource::Invalid,
+                                                TextureSource::Invalid,
+                                            ],
+                                        };
+                                        let batch_params = BrushBatchParameters::shared(
+                                            BrushBatchKind::Image(ImageBufferKind::Texture2D),
+                                            textures,
+                                            ImageBrushData {
+                                                color_mode: ShaderColorMode::Image,
+                                                alpha_type: AlphaType::PremultipliedAlpha,
+                                                raster_space: RasterizationSpace::Screen,
+                                                opacity: 1.0,
+                                            }.encode(),
+                                            uv_rect_address,
+                                        );
+
+                                        let is_segmented =
+                                            segment_instance_index != SegmentInstanceIndex::INVALID &&
+                                            segment_instance_index != SegmentInstanceIndex::UNUSED;
+
+                                        let (prim_cache_address, segments) = if is_segmented {
+                                            let segment_instance = &ctx.scratch.segment_instances[segment_instance_index];
+                                            let segments = Some(&ctx.scratch.segments[segment_instance.segments_range]);
+                                            (gpu_cache.get_address(&segment_instance.gpu_cache_handle), segments)
+                                        } else {
+                                            (prim_cache_address, None)
+                                        };
+
+                                        let prim_header = PrimitiveHeader {
+                                            specific_prim_address: prim_cache_address,
+                                            ..prim_header
+                                        };
+
+                                        let prim_header_index = prim_headers.push(
+                                            &prim_header,
+                                            z_id,
+                                            batch_params.prim_user_data,
+                                        );
+
+                                        let (opacity, blend_mode) = if is_opaque {
+                                            (PrimitiveOpacity::opaque(), BlendMode::None)
+                                        } else {
+                                            (PrimitiveOpacity::translucent(), BlendMode::PremultipliedAlpha)
+                                        };
+
+                                        self.add_segmented_prim_to_batch(
+                                            segments,
+                                            opacity,
+                                            &batch_params,
+                                            blend_mode,
+                                            batch_features,
+                                            brush_flags,
+                                            EdgeAaSegmentMask::all(),
+                                            prim_header_index,
+                                            bounding_rect,
+                                            transform_kind,
+                                            z_id,
+                                            prim_info.clip_task_index,
+                                            ctx,
+                                            render_tasks,
+                                        );
+                                    }
+                                }
+                            }
+                            PictureCompositeMode::SvgFilter(..) => {
+                                let (clip_task_address, clip_mask_texture_id) = ctx.get_prim_clip_task_and_texture(
+                                    prim_info.clip_task_index,
+                                    render_tasks,
+                                ).unwrap();
+
+                                let kind = BatchKind::Brush(
+                                    BrushBatchKind::Image(ImageBufferKind::Texture2D)
+                                );
+                                let (uv_rect_address, texture) = render_tasks.resolve_location(
+                                    pic_task_id,
+                                    gpu_cache,
+                                ).unwrap();
+                                let textures = BatchTextures::prim_textured(
+                                    texture,
+                                    clip_mask_texture_id,
+                                );
+                                let key = BatchKey::new(
+                                    kind,
+                                    blend_mode,
+                                    textures,
+                                );
+                                let prim_header_index = prim_headers.push(
+                                    &prim_header,
+                                    z_id,
+                                    ImageBrushData {
+                                        color_mode: ShaderColorMode::Image,
+                                        alpha_type: AlphaType::PremultipliedAlpha,
+                                        raster_space: RasterizationSpace::Screen,
+                                        opacity: 1.0,
+                                    }.encode(),
+                                );
+
+                                self.add_brush_instance_to_batches(
+                                    key,
+                                    batch_features,
+                                    bounding_rect,
+                                    z_id,
+                                    INVALID_SEGMENT_INDEX,
+                                    EdgeAaSegmentMask::all(),
+                                    clip_task_address,
+                                    brush_flags,
+                                    prim_header_index,
+                                    uv_rect_address.as_int(),
+                                );
+                            }
+                        }
+                    }
+                    None => {
+                        unreachable!();
+                    }
+                }
+            }
+            PrimitiveInstanceKind::ImageBorder { data_handle, .. } => {
+                let prim_data = &ctx.data_stores.image_border[data_handle];
+                let common_data = &prim_data.common;
+                let border_data = &prim_data.kind;
+
+                let (uv_rect_address, texture) = match render_tasks.resolve_location(border_data.src_color, gpu_cache) {
+                    Some(src) => src,
+                    None => {
+                        return;
+                    }
+                };
+
+                let textures = TextureSet::prim_textured(texture);
+                let prim_cache_address = gpu_cache.get_address(&common_data.gpu_cache_handle);
+                let blend_mode = if !common_data.opacity.is_opaque ||
+                    prim_info.clip_task_index != ClipTaskIndex::INVALID ||
+                    transform_kind == TransformedRectKind::Complex ||
+                    is_anti_aliased
+                {
+                    BlendMode::PremultipliedAlpha
+                } else {
+                    BlendMode::None
+                };
+
+                let prim_header = PrimitiveHeader {
+                    local_rect: prim_rect,
+                    local_clip_rect: prim_info.clip_chain.local_clip_rect,
+                    specific_prim_address: prim_cache_address,
+                    transform_id,
+                };
+
+                let batch_params = BrushBatchParameters::shared(
+                    BrushBatchKind::Image(texture.image_buffer_kind()),
+                    textures,
+                    ImageBrushData {
+                        color_mode: ShaderColorMode::Image,
+                        alpha_type: AlphaType::PremultipliedAlpha,
+                        raster_space: RasterizationSpace::Local,
+                        opacity: 1.0,
+                    }.encode(),
+                    uv_rect_address.as_int(),
+                );
+
+                let prim_header_index = prim_headers.push(
+                    &prim_header,
+                    z_id,
+                    batch_params.prim_user_data,
+                );
+
+                self.add_segmented_prim_to_batch(
+                    Some(border_data.brush_segments.as_slice()),
+                    common_data.opacity,
+                    &batch_params,
+                    blend_mode,
+                    batch_features,
+                    brush_flags,
+                    common_data.edge_aa_mask,
+                    prim_header_index,
+                    bounding_rect,
+                    transform_kind,
+                    z_id,
+                    prim_info.clip_task_index,
+                    ctx,
+                    render_tasks,
+                );
+            }
+            PrimitiveInstanceKind::Rectangle { data_handle, segment_instance_index, use_legacy_path, .. } => {
+                debug_assert!(use_legacy_path);
+                let prim_data = &ctx.data_stores.prim[data_handle];
+
+                let blend_mode = if !prim_data.opacity.is_opaque ||
+                    prim_info.clip_task_index != ClipTaskIndex::INVALID ||
+                    transform_kind == TransformedRectKind::Complex ||
+                    is_anti_aliased
+                {
+                    BlendMode::PremultipliedAlpha
+                } else {
+                    BlendMode::None
+                };
+
+                let batch_params = BrushBatchParameters::shared(
+                    BrushBatchKind::Solid,
+                    TextureSet::UNTEXTURED,
+                    [get_shader_opacity(1.0), 0, 0, 0],
+                    0,
+                );
+
+                let (prim_cache_address, segments) = if segment_instance_index == SegmentInstanceIndex::UNUSED {
+                    (gpu_cache.get_address(&prim_data.gpu_cache_handle), None)
+                } else {
+                    let segment_instance = &ctx.scratch.segment_instances[segment_instance_index];
+                    let segments = Some(&ctx.scratch.segments[segment_instance.segments_range]);
+                    (gpu_cache.get_address(&segment_instance.gpu_cache_handle), segments)
+                };
+
+                let prim_header = PrimitiveHeader {
+                    local_rect: prim_rect,
+                    local_clip_rect: prim_info.clip_chain.local_clip_rect,
+                    specific_prim_address: prim_cache_address,
+                    transform_id,
+                };
+
+                let prim_header_index = prim_headers.push(
+                    &prim_header,
+                    z_id,
+                    batch_params.prim_user_data,
+                );
+
+                self.add_segmented_prim_to_batch(
+                    segments,
+                    prim_data.opacity,
+                    &batch_params,
+                    blend_mode,
+                    batch_features,
+                    brush_flags,
+                    prim_data.edge_aa_mask,
+                    prim_header_index,
+                    bounding_rect,
+                    transform_kind,
+                    z_id,
+                    prim_info.clip_task_index,
+                    ctx,
+                    render_tasks,
+                );
+            }
+            PrimitiveInstanceKind::YuvImage { data_handle, segment_instance_index, is_compositor_surface, .. } => {
+                debug_assert!(!is_compositor_surface);
+
+                let yuv_image_data = &ctx.data_stores.yuv_image[data_handle].kind;
+                let mut textures = TextureSet::UNTEXTURED;
+                let mut uv_rect_addresses = [0; 3];
+
+                //yuv channel
+                let channel_count = yuv_image_data.format.get_plane_num();
+                debug_assert!(channel_count <= 3);
+                for channel in 0 .. channel_count {
+
+                    let src_channel = render_tasks.resolve_location(yuv_image_data.src_yuv[channel], gpu_cache);
+
+                    let (uv_rect_address, texture_source) = match src_channel {
+                        Some(src) => src,
+                        None => {
+                            warn!("Warnings: skip a PrimitiveKind::YuvImage");
+                            return;
+                        }
+                    };
+
+                    textures.colors[channel] = texture_source;
+                    uv_rect_addresses[channel] = uv_rect_address.as_int();
+                }
+
+                // All yuv textures should be the same type.
+                let buffer_kind = textures.colors[0].image_buffer_kind();
+                assert!(
+                    textures.colors[1 .. yuv_image_data.format.get_plane_num()]
+                        .iter()
+                        .all(|&tid| buffer_kind == tid.image_buffer_kind())
+                );
+
+                let kind = BrushBatchKind::YuvImage(
+                    buffer_kind,
+                    yuv_image_data.format,
+                    yuv_image_data.color_depth,
+                    yuv_image_data.color_space,
+                    yuv_image_data.color_range,
+                );
+
+                let batch_params = BrushBatchParameters::shared(
+                    kind,
+                    textures,
+                    [
+                        uv_rect_addresses[0],
+                        uv_rect_addresses[1],
+                        uv_rect_addresses[2],
+                        0,
+                    ],
+                    0,
+                );
+
+                let prim_common_data = ctx.data_stores.as_common_data(&prim_instance);
+
+                let blend_mode = if !prim_common_data.opacity.is_opaque ||
+                    prim_info.clip_task_index != ClipTaskIndex::INVALID ||
+                    transform_kind == TransformedRectKind::Complex ||
+                    is_anti_aliased
+                {
+                    BlendMode::PremultipliedAlpha
+                } else {
+                    BlendMode::None
+                };
+
+                debug_assert_ne!(segment_instance_index, SegmentInstanceIndex::INVALID);
+                let (prim_cache_address, segments) = if segment_instance_index == SegmentInstanceIndex::UNUSED {
+                    (gpu_cache.get_address(&prim_common_data.gpu_cache_handle), None)
+                } else {
+                    let segment_instance = &ctx.scratch.segment_instances[segment_instance_index];
+                    let segments = Some(&ctx.scratch.segments[segment_instance.segments_range]);
+                    (gpu_cache.get_address(&segment_instance.gpu_cache_handle), segments)
+                };
+
+                let prim_header = PrimitiveHeader {
+                    local_rect: prim_rect,
+                    local_clip_rect: prim_info.clip_chain.local_clip_rect,
+                    specific_prim_address: prim_cache_address,
+                    transform_id,
+                };
+
+                let prim_header_index = prim_headers.push(
+                    &prim_header,
+                    z_id,
+                    batch_params.prim_user_data,
+                );
+
+                self.add_segmented_prim_to_batch(
+                    segments,
+                    prim_common_data.opacity,
+                    &batch_params,
+                    blend_mode,
+                    batch_features,
+                    brush_flags,
+                    prim_common_data.edge_aa_mask,
+                    prim_header_index,
+                    bounding_rect,
+                    transform_kind,
+                    z_id,
+                    prim_info.clip_task_index,
+                    ctx,
+                    render_tasks,
+                );
+            }
+            PrimitiveInstanceKind::Image { data_handle, image_instance_index, is_compositor_surface, .. } => {
+                debug_assert!(!is_compositor_surface);
+
+                let image_data = &ctx.data_stores.image[data_handle].kind;
+                let common_data = &ctx.data_stores.image[data_handle].common;
+                let image_instance = &ctx.prim_store.images[image_instance_index];
+                let prim_user_data = ImageBrushData {
+                    color_mode: ShaderColorMode::Image,
+                    alpha_type: image_data.alpha_type,
+                    raster_space: RasterizationSpace::Local,
+                    opacity: 1.0,
+                }.encode();
+
+                let blend_mode = if !common_data.opacity.is_opaque ||
+                    prim_info.clip_task_index != ClipTaskIndex::INVALID ||
+                    transform_kind == TransformedRectKind::Complex ||
+                    is_anti_aliased
+                {
+                    match image_data.alpha_type {
+                        AlphaType::PremultipliedAlpha => BlendMode::PremultipliedAlpha,
+                        AlphaType::Alpha => BlendMode::Alpha,
+                    }
+                } else {
+                    BlendMode::None
+                };
+
+                if image_instance.visible_tiles.is_empty() {
+                    if cfg!(debug_assertions) {
+                        match ctx.resource_cache.get_image_properties(image_data.key) {
+                            Some(ImageProperties { tiling: None, .. }) | None => (),
+                            other => panic!("Non-tiled image with no visible images detected! Properties {:?}", other),
+                        }
+                    }
+
+                    let src_color = render_tasks.resolve_location(image_instance.src_color, gpu_cache);
+
+                    let (uv_rect_address, texture_source) = match src_color {
+                        Some(src) => src,
+                        None => {
+                            return;
+                        }
+                    };
+
+                    let batch_params = BrushBatchParameters::shared(
+                        BrushBatchKind::Image(texture_source.image_buffer_kind()),
+                        TextureSet::prim_textured(texture_source),
+                        prim_user_data,
+                        uv_rect_address.as_int(),
+                    );
+
+                    debug_assert_ne!(image_instance.segment_instance_index, SegmentInstanceIndex::INVALID);
+                    let (prim_cache_address, segments) = if image_instance.segment_instance_index == SegmentInstanceIndex::UNUSED {
+                        (gpu_cache.get_address(&common_data.gpu_cache_handle), None)
+                    } else {
+                        let segment_instance = &ctx.scratch.segment_instances[image_instance.segment_instance_index];
+                        let segments = Some(&ctx.scratch.segments[segment_instance.segments_range]);
+                        (gpu_cache.get_address(&segment_instance.gpu_cache_handle), segments)
+                    };
+
+                    let prim_header = PrimitiveHeader {
+                        local_rect: prim_rect,
+                        local_clip_rect: prim_info.clip_chain.local_clip_rect,
+                        specific_prim_address: prim_cache_address,
+                        transform_id,
+                    };
+
+                    let prim_header_index = prim_headers.push(
+                        &prim_header,
+                        z_id,
+                        batch_params.prim_user_data,
+                    );
+
+                    self.add_segmented_prim_to_batch(
+                        segments,
+                        common_data.opacity,
+                        &batch_params,
+                        blend_mode,
+                        batch_features,
+                        brush_flags,
+                        common_data.edge_aa_mask,
+                        prim_header_index,
+                        bounding_rect,
+                        transform_kind,
+                        z_id,
+                        prim_info.clip_task_index,
+                        ctx,
+                        render_tasks,
+                    );
+                } else {
+                    const VECS_PER_SPECIFIC_BRUSH: usize = 3;
+                    let max_tiles_per_header = (MAX_VERTEX_TEXTURE_WIDTH - VECS_PER_SPECIFIC_BRUSH) / VECS_PER_SEGMENT;
+
+                    let (clip_task_address, clip_mask_texture_id) = ctx.get_prim_clip_task_and_texture(
+                        prim_info.clip_task_index,
+                        render_tasks,
+                    ).unwrap();
+
+                    // use temporary block storage since we don't know the number of visible tiles beforehand
+                    let mut gpu_blocks = Vec::<GpuBlockData>::with_capacity(3 + max_tiles_per_header * 2);
+                    for chunk in image_instance.visible_tiles.chunks(max_tiles_per_header) {
+                        gpu_blocks.clear();
+                        gpu_blocks.push(image_data.color.premultiplied().into()); //color
+                        gpu_blocks.push(PremultipliedColorF::WHITE.into()); //bg color
+                        gpu_blocks.push([-1.0, 0.0, 0.0, 0.0].into()); //stretch size
+                        // negative first value makes the shader code ignore it and use the local size instead
+                        for tile in chunk {
+                            let tile_rect = tile.local_rect.translate(-prim_rect.min.to_vector());
+                            gpu_blocks.push(tile_rect.into());
+                            gpu_blocks.push(GpuBlockData::EMPTY);
+                        }
+
+                        let gpu_handle = gpu_cache.push_per_frame_blocks(&gpu_blocks);
+                        let prim_header = PrimitiveHeader {
+                            local_rect: prim_rect,
+                            local_clip_rect: image_instance.tight_local_clip_rect,
+                            specific_prim_address: gpu_cache.get_address(&gpu_handle),
+                            transform_id,
+                        };
+                        let prim_header_index = prim_headers.push(&prim_header, z_id, prim_user_data);
+
+                        for (i, tile) in chunk.iter().enumerate() {
+                            let (uv_rect_address, texture) = match render_tasks.resolve_location(tile.src_color, gpu_cache) {
+                                Some(result) => result,
+                                None => {
+                                    return;
+                                }
+                            };
+
+                            let textures = BatchTextures::prim_textured(
+                                texture,
+                                clip_mask_texture_id,
+                            );
+
+                            let batch_key = BatchKey {
+                                blend_mode,
+                                kind: BatchKind::Brush(BrushBatchKind::Image(texture.image_buffer_kind())),
+                                textures,
+                            };
+
+                            self.add_brush_instance_to_batches(
+                                batch_key,
+                                batch_features,
+                                bounding_rect,
+                                z_id,
+                                i as i32,
+                                tile.edge_flags,
+                                clip_task_address,
+                                brush_flags | BrushFlags::SEGMENT_RELATIVE | BrushFlags::PERSPECTIVE_INTERPOLATION,
+                                prim_header_index,
+                                uv_rect_address.as_int(),
+                            );
+                        }
+                    }
+                }
+            }
+            PrimitiveInstanceKind::LinearGradient { data_handle, ref visible_tiles_range, .. } => {
+                let prim_data = &ctx.data_stores.linear_grad[data_handle];
+
+                let mut prim_header = PrimitiveHeader {
+                    local_rect: prim_rect,
+                    local_clip_rect: prim_info.clip_chain.local_clip_rect,
+                    specific_prim_address: GpuCacheAddress::INVALID,
+                    transform_id,
+                };
+
+                let blend_mode = if !prim_data.opacity.is_opaque ||
+                    prim_info.clip_task_index != ClipTaskIndex::INVALID ||
+                    transform_kind == TransformedRectKind::Complex ||
+                    is_anti_aliased
+                {
+                    BlendMode::PremultipliedAlpha
+                } else {
+                    BlendMode::None
+                };
+
+                let user_data = [extra_prim_gpu_address.unwrap(), 0, 0, 0];
+
+                if visible_tiles_range.is_empty() {
+                    let batch_params = BrushBatchParameters::shared(
+                        BrushBatchKind::LinearGradient,
+                        TextureSet::UNTEXTURED,
+                        user_data,
+                        0,
+                    );
+
+                    prim_header.specific_prim_address = gpu_cache.get_address(&prim_data.gpu_cache_handle);
+
+                    let prim_header_index = prim_headers.push(&prim_header, z_id, user_data);
+
+                    let segments = if prim_data.brush_segments.is_empty() {
+                        None
+                    } else {
+                        Some(prim_data.brush_segments.as_slice())
+                    };
+                    self.add_segmented_prim_to_batch(
+                        segments,
+                        prim_data.opacity,
+                        &batch_params,
+                        blend_mode,
+                        batch_features,
+                        brush_flags,
+                        prim_data.edge_aa_mask,
+                        prim_header_index,
+                        bounding_rect,
+                        transform_kind,
+                        z_id,
+                        prim_info.clip_task_index,
+                        ctx,
+                        render_tasks,
+                    );
+                } else {
+                    let visible_tiles = &ctx.scratch.gradient_tiles[*visible_tiles_range];
+
+                    let (clip_task_address, clip_mask_texture_id) = ctx.get_prim_clip_task_and_texture(
+                        prim_info.clip_task_index,
+                        render_tasks,
+                    ).unwrap();
+
+                    let key = BatchKey {
+                        blend_mode,
+                        kind: BatchKind::Brush(BrushBatchKind::LinearGradient),
+                        textures: BatchTextures::prim_untextured(clip_mask_texture_id),
+                    };
+
+                    for tile in visible_tiles {
+                        let tile_prim_header = PrimitiveHeader {
+                            specific_prim_address: gpu_cache.get_address(&tile.handle),
+                            local_rect: tile.local_rect,
+                            local_clip_rect: tile.local_clip_rect,
+                            ..prim_header
+                        };
+                        let prim_header_index = prim_headers.push(&tile_prim_header, z_id, user_data);
+
+                        self.add_brush_instance_to_batches(
+                            key,
+                            batch_features,
+                            bounding_rect,
+                            z_id,
+                            INVALID_SEGMENT_INDEX,
+                            prim_data.edge_aa_mask,
+                            clip_task_address,
+                            brush_flags | BrushFlags::PERSPECTIVE_INTERPOLATION,
+                            prim_header_index,
+                            0,
+                        );
+                    }
+                }
+            }
+            PrimitiveInstanceKind::CachedLinearGradient { data_handle, ref visible_tiles_range, .. } => {
+                let prim_data = &ctx.data_stores.linear_grad[data_handle];
+                let common_data = &prim_data.common;
+
+                let src_color = render_tasks.resolve_location(prim_data.src_color, gpu_cache);
+
+                let (uv_rect_address, texture_source) = match src_color {
+                    Some(src) => src,
+                    None => {
+                        return;
+                    }
+                };
+
+                let textures = TextureSet::prim_textured(texture_source);
+
+                let prim_header = PrimitiveHeader {
+                    local_rect: prim_rect,
+                    local_clip_rect: prim_info.clip_chain.local_clip_rect,
+                    specific_prim_address: gpu_cache.get_address(&common_data.gpu_cache_handle),
+                    transform_id,
+                };
+
+                let prim_user_data = ImageBrushData {
+                    color_mode: ShaderColorMode::Image,
+                    alpha_type: AlphaType::PremultipliedAlpha,
+                    raster_space: RasterizationSpace::Local,
+                    opacity: 1.0,
+                }.encode();
+
+                let blend_mode = if !common_data.opacity.is_opaque ||
+                    prim_info.clip_task_index != ClipTaskIndex::INVALID ||
+                    transform_kind == TransformedRectKind::Complex ||
+                    is_anti_aliased
+                {
+                    BlendMode::PremultipliedAlpha
+                } else {
+                    BlendMode::None
+                };
+
+                let batch_kind = BrushBatchKind::Image(texture_source.image_buffer_kind());
+
+                if visible_tiles_range.is_empty() {
+                    let batch_params = BrushBatchParameters::shared(
+                        batch_kind,
+                        textures,
+                        prim_user_data,
+                        uv_rect_address.as_int(),
+                    );
+
+                    let segments = if prim_data.brush_segments.is_empty() {
+                        None
+                    } else {
+                        Some(&prim_data.brush_segments[..])
+                    };
+
+                    let prim_header_index = prim_headers.push(
+                        &prim_header,
+                        z_id,
+                        batch_params.prim_user_data,
+                    );
+
+                    self.add_segmented_prim_to_batch(
+                        segments,
+                        common_data.opacity,
+                        &batch_params,
+                        blend_mode,
+                        batch_features,
+                        brush_flags,
+                        common_data.edge_aa_mask,
+                        prim_header_index,
+                        bounding_rect,
+                        transform_kind,
+                        z_id,
+                        prim_info.clip_task_index,
+                        ctx,
+                        render_tasks,
+                    );
+                } else {
+                    let visible_tiles = &ctx.scratch.gradient_tiles[*visible_tiles_range];
+
+                    let (clip_task_address, clip_mask) = ctx.get_prim_clip_task_and_texture(
+                        prim_info.clip_task_index,
+                        render_tasks,
+                    ).unwrap();
+
+                    let batch_key = BatchKey {
+                        blend_mode,
+                        kind: BatchKind::Brush(batch_kind),
+                        textures: BatchTextures {
+                            input: textures,
+                            clip_mask,
+                        },
+                    };
+
+                    for tile in visible_tiles {
+                        let tile_prim_header = PrimitiveHeader {
+                            local_rect: tile.local_rect,
+                            local_clip_rect: tile.local_clip_rect,
+                            ..prim_header
+                        };
+                        let prim_header_index = prim_headers.push(&tile_prim_header, z_id, prim_user_data);
+
+                        self.add_brush_instance_to_batches(
+                            batch_key,
+                            batch_features,
+                            bounding_rect,
+                            z_id,
+                            INVALID_SEGMENT_INDEX,
+                            prim_data.edge_aa_mask,
+                            clip_task_address,
+                            brush_flags | BrushFlags::PERSPECTIVE_INTERPOLATION,
+                            prim_header_index,
+                            uv_rect_address.as_int(),
+                        );
+                    }
+                }
+            }
+            PrimitiveInstanceKind::RadialGradient { data_handle, ref visible_tiles_range, .. } => {
+                let prim_data = &ctx.data_stores.radial_grad[data_handle];
+                let common_data = &prim_data.common;
+
+                let src_color = render_tasks.resolve_location(prim_data.src_color, gpu_cache);
+
+                let (uv_rect_address, texture_source) = match src_color {
+                    Some(src) => src,
+                    None => {
+                        return;
+                    }
+                };
+
+                let textures = TextureSet::prim_textured(texture_source);
+
+                let prim_header = PrimitiveHeader {
+                    local_rect: prim_rect,
+                    local_clip_rect: prim_info.clip_chain.local_clip_rect,
+                    specific_prim_address: gpu_cache.get_address(&common_data.gpu_cache_handle),
+                    transform_id,
+                };
+
+                let prim_user_data = ImageBrushData {
+                    color_mode: ShaderColorMode::Image,
+                    alpha_type: AlphaType::PremultipliedAlpha,
+                    raster_space: RasterizationSpace::Local,
+                    opacity: 1.0,
+                }.encode();
+
+
+                let blend_mode = if !common_data.opacity.is_opaque ||
+                    prim_info.clip_task_index != ClipTaskIndex::INVALID ||
+                    transform_kind == TransformedRectKind::Complex ||
+                    is_anti_aliased
+                {
+                    BlendMode::PremultipliedAlpha
+                } else {
+                    BlendMode::None
+                };
+
+                let batch_kind = BrushBatchKind::Image(texture_source.image_buffer_kind());
+
+                if visible_tiles_range.is_empty() {
+                    let batch_params = BrushBatchParameters::shared(
+                        batch_kind,
+                        textures,
+                        prim_user_data,
+                        uv_rect_address.as_int(),
+                    );
+
+                    let segments = if prim_data.brush_segments.is_empty() {
+                        None
+                    } else {
+                        Some(&prim_data.brush_segments[..])
+                    };
+
+                    let prim_header_index = prim_headers.push(
+                        &prim_header,
+                        z_id,
+                        batch_params.prim_user_data,
+                    );
+
+                    self.add_segmented_prim_to_batch(
+                        segments,
+                        common_data.opacity,
+                        &batch_params,
+                        blend_mode,
+                        batch_features,
+                        brush_flags,
+                        prim_data.edge_aa_mask,
+                        prim_header_index,
+                        bounding_rect,
+                        transform_kind,
+                        z_id,
+                        prim_info.clip_task_index,
+                        ctx,
+                        render_tasks,
+                    );
+                } else {
+                    let visible_tiles = &ctx.scratch.gradient_tiles[*visible_tiles_range];
+
+                    let (clip_task_address, clip_mask) = ctx.get_prim_clip_task_and_texture(
+                        prim_info.clip_task_index,
+                        render_tasks,
+                    ).unwrap();
+
+                    let batch_key = BatchKey {
+                        blend_mode,
+                        kind: BatchKind::Brush(batch_kind),
+                        textures: BatchTextures {
+                            input: textures,
+                            clip_mask,
+                        },
+                    };
+
+                    for tile in visible_tiles {
+                        let tile_prim_header = PrimitiveHeader {
+                            local_rect: tile.local_rect,
+                            local_clip_rect: tile.local_clip_rect,
+                            ..prim_header
+                        };
+                        let prim_header_index = prim_headers.push(&tile_prim_header, z_id, prim_user_data);
+
+                        self.add_brush_instance_to_batches(
+                            batch_key,
+                            batch_features,
+                            bounding_rect,
+                            z_id,
+                            INVALID_SEGMENT_INDEX,
+                            prim_data.edge_aa_mask,
+                            clip_task_address,
+                            brush_flags | BrushFlags::PERSPECTIVE_INTERPOLATION,
+                            prim_header_index,
+                            uv_rect_address.as_int(),
+                        );
+                    }
+                }
+
+            }
+            PrimitiveInstanceKind::ConicGradient { data_handle, ref visible_tiles_range, .. } => {
+                let prim_data = &ctx.data_stores.conic_grad[data_handle];
+                let common_data = &prim_data.common;
+
+                let src_color = render_tasks.resolve_location(prim_data.src_color, gpu_cache);
+
+                let (uv_rect_address, texture_source) = match src_color {
+                    Some(src) => src,
+                    None => {
+                        return;
+                    }
+                };
+
+                let textures = TextureSet::prim_textured(texture_source);
+
+                let prim_header = PrimitiveHeader {
+                    local_rect: prim_rect,
+                    local_clip_rect: prim_info.clip_chain.local_clip_rect,
+                    specific_prim_address: gpu_cache.get_address(&common_data.gpu_cache_handle),
+                    transform_id,
+                };
+
+                let prim_user_data = ImageBrushData {
+                    color_mode: ShaderColorMode::Image,
+                    alpha_type: AlphaType::PremultipliedAlpha,
+                    raster_space: RasterizationSpace::Local,
+                    opacity: 1.0,
+                }.encode();
+
+
+                let blend_mode = if !common_data.opacity.is_opaque ||
+                    prim_info.clip_task_index != ClipTaskIndex::INVALID ||
+                    transform_kind == TransformedRectKind::Complex ||
+                    is_anti_aliased
+                {
+                    BlendMode::PremultipliedAlpha
+                } else {
+                    BlendMode::None
+                };
+
+                let batch_kind = BrushBatchKind::Image(texture_source.image_buffer_kind());
+
+                if visible_tiles_range.is_empty() {
+                    let batch_params = BrushBatchParameters::shared(
+                        batch_kind,
+                        textures,
+                        prim_user_data,
+                        uv_rect_address.as_int(),
+                    );
+
+                    let segments = if prim_data.brush_segments.is_empty() {
+                        None
+                    } else {
+                        Some(&prim_data.brush_segments[..])
+                    };
+
+                    let prim_header_index = prim_headers.push(
+                        &prim_header,
+                        z_id,
+                        batch_params.prim_user_data,
+                    );
+
+                    self.add_segmented_prim_to_batch(
+                        segments,
+                        common_data.opacity,
+                        &batch_params,
+                        blend_mode,
+                        batch_features,
+                        brush_flags,
+                        prim_data.edge_aa_mask,
+                        prim_header_index,
+                        bounding_rect,
+                        transform_kind,
+                        z_id,
+                        prim_info.clip_task_index,
+                        ctx,
+                        render_tasks,
+                    );
+                } else {
+                    let visible_tiles = &ctx.scratch.gradient_tiles[*visible_tiles_range];
+
+                    let (clip_task_address, clip_mask) = ctx.get_prim_clip_task_and_texture(
+                        prim_info.clip_task_index,
+                        render_tasks,
+                    ).unwrap();
+
+                    let batch_key = BatchKey {
+                        blend_mode,
+                        kind: BatchKind::Brush(batch_kind),
+                        textures: BatchTextures {
+                            input: textures,
+                            clip_mask,
+                        },
+                    };
+
+                    for tile in visible_tiles {
+                        let tile_prim_header = PrimitiveHeader {
+                            local_rect: tile.local_rect,
+                            local_clip_rect: tile.local_clip_rect,
+                            ..prim_header
+                        };
+                        let prim_header_index = prim_headers.push(&tile_prim_header, z_id, prim_user_data);
+
+                        self.add_brush_instance_to_batches(
+                            batch_key,
+                            batch_features,
+                            bounding_rect,
+                            z_id,
+                            INVALID_SEGMENT_INDEX,
+                            prim_data.edge_aa_mask,
+                            clip_task_address,
+                            brush_flags | BrushFlags::PERSPECTIVE_INTERPOLATION,
+                            prim_header_index,
+                            uv_rect_address.as_int(),
+                        );
+                    }
+                }
+            }
+            PrimitiveInstanceKind::BackdropCapture { .. } => {}
+            PrimitiveInstanceKind::BackdropRender { pic_index, .. } => {
+                let prim_cache_address = gpu_cache.get_address(&ctx.globals.default_image_handle);
+                let blend_mode = BlendMode::PremultipliedAlpha;
+                let pic_task_id = ctx.prim_store.pictures[pic_index.0].primary_render_task_id;
+
+                let prim_header = PrimitiveHeader {
+                    local_rect: prim_rect,
+                    local_clip_rect: prim_info.clip_chain.local_clip_rect,
+                    specific_prim_address: prim_cache_address,
+                    transform_id,
+                };
+
+                let (clip_task_address, clip_mask_texture_id) = ctx.get_prim_clip_task_and_texture(
+                    prim_info.clip_task_index,
+                    render_tasks,
+                ).unwrap();
+
+                let kind = BatchKind::Brush(
+                    BrushBatchKind::Image(ImageBufferKind::Texture2D)
+                );
+                let (_, texture) = render_tasks.resolve_location(
+                    pic_task_id,
+                    gpu_cache,
+                ).unwrap();
+                let textures = BatchTextures::prim_textured(
+                    texture,
+                    clip_mask_texture_id,
+                );
+                let key = BatchKey::new(
+                    kind,
+                    blend_mode,
+                    textures,
+                );
+                let prim_header_index = prim_headers.push(
+                    &prim_header,
+                    z_id,
+                    ImageBrushData {
+                        color_mode: ShaderColorMode::Image,
+                        alpha_type: AlphaType::PremultipliedAlpha,
+                        raster_space: RasterizationSpace::Screen,
+                        opacity: 1.0,
+                    }.encode(),
+                );
+
+                let pic_task = &render_tasks[pic_task_id.unwrap()];
+                let pic_info = match pic_task.kind {
+                    RenderTaskKind::Picture(ref info) => info,
+                    _ => panic!("bug: not a picture"),
+                };
+                let target_rect = pic_task.get_target_rect();
+
+                let backdrop_rect = DeviceRect::from_origin_and_size(
+                    pic_info.content_origin,
+                    target_rect.size().to_f32(),
+                );
+
+                let map_prim_to_backdrop = SpaceMapper::new_with_target(
+                    pic_info.surface_spatial_node_index,
+                    prim_spatial_node_index,
+                    WorldRect::max_rect(),
+                    ctx.spatial_tree,
+                );
+
+                let points = [
+                    map_prim_to_backdrop.map_point(prim_rect.top_left()),
+                    map_prim_to_backdrop.map_point(prim_rect.top_right()),
+                    map_prim_to_backdrop.map_point(prim_rect.bottom_left()),
+                    map_prim_to_backdrop.map_point(prim_rect.bottom_right()),
+                ];
+
+                if points.iter().any(|p| p.is_none()) {
+                    return;
+                }
+
+                let uvs = [
+                    calculate_screen_uv(points[0].unwrap() * pic_info.device_pixel_scale, backdrop_rect),
+                    calculate_screen_uv(points[1].unwrap() * pic_info.device_pixel_scale, backdrop_rect),
+                    calculate_screen_uv(points[2].unwrap() * pic_info.device_pixel_scale, backdrop_rect),
+                    calculate_screen_uv(points[3].unwrap() * pic_info.device_pixel_scale, backdrop_rect),
+                ];
+
+                // TODO (gw): This is a hack that provides the GPU cache blocks for an
+                //            ImageSource. We should update the GPU cache interfaces to
+                //            allow pushing per-frame blocks via a request interface.
+                let gpu_blocks = &[
+                    GpuBlockData::from([
+                        target_rect.min.x as f32,
+                        target_rect.min.y as f32,
+                        target_rect.max.x as f32,
+                        target_rect.max.y as f32,
+                    ]),
+                    GpuBlockData::from([0.0; 4]),
+                    GpuBlockData::from(uvs[0]),
+                    GpuBlockData::from(uvs[1]),
+                    GpuBlockData::from(uvs[2]),
+                    GpuBlockData::from(uvs[3]),
+                ];
+                let uv_rect_handle = gpu_cache.push_per_frame_blocks(gpu_blocks);
+
+                self.add_brush_instance_to_batches(
+                    key,
+                    batch_features,
+                    bounding_rect,
+                    z_id,
+                    INVALID_SEGMENT_INDEX,
+                    EdgeAaSegmentMask::all(),
+                    clip_task_address,
+                    brush_flags,
+                    prim_header_index,
+                    uv_rect_handle.as_int(gpu_cache),
+                );
+            }
+        }
+    }
+
+    /// Add a single segment instance to a batch.
+    ///
+    /// `edge_aa_mask` Specifies the edges that are *allowed* to have anti-aliasing, if and only
+    /// if the segments enable it.
+    /// In other words passing EdgeAaSegmentFlags::all() does not necessarily mean all edges will
+    /// be anti-aliased, only that they could be.
+    fn add_segment_to_batch(
+        &mut self,
+        segment: &BrushSegment,
+        segment_data: &SegmentInstanceData,
+        segment_index: i32,
+        batch_kind: BrushBatchKind,
+        prim_header_index: PrimitiveHeaderIndex,
+        alpha_blend_mode: BlendMode,
+        features: BatchFeatures,
+        brush_flags: BrushFlags,
+        edge_aa_mask: EdgeAaSegmentMask,
+        bounding_rect: &PictureRect,
+        transform_kind: TransformedRectKind,
+        z_id: ZBufferId,
+        prim_opacity: PrimitiveOpacity,
+        clip_task_index: ClipTaskIndex,
+        ctx: &RenderTargetContext,
+        render_tasks: &RenderTaskGraph,
+    ) {
+        debug_assert!(clip_task_index != ClipTaskIndex::INVALID);
+
+        // Get GPU address of clip task for this segment, or None if
+        // the entire segment is clipped out.
+        if let Some((clip_task_address, clip_mask)) = ctx.get_clip_task_and_texture(
+            clip_task_index,
+            segment_index,
+            render_tasks,
+        ) {
+            // If a got a valid (or OPAQUE) clip task address, add the segment.
+            let is_inner = segment.edge_flags.is_empty();
+            let needs_blending = !prim_opacity.is_opaque ||
+                                 clip_task_address != OPAQUE_TASK_ADDRESS ||
+                                 (!is_inner && transform_kind == TransformedRectKind::Complex) ||
+                                 brush_flags.contains(BrushFlags::FORCE_AA);
+
+            let textures = BatchTextures {
+                input: segment_data.textures,
+                clip_mask,
+            };
+
+            let batch_key = BatchKey {
+                blend_mode: if needs_blending { alpha_blend_mode } else { BlendMode::None },
+                kind: BatchKind::Brush(batch_kind),
+                textures,
+            };
+
+            self.add_brush_instance_to_batches(
+                batch_key,
+                features,
+                bounding_rect,
+                z_id,
+                segment_index,
+                segment.edge_flags & edge_aa_mask,
+                clip_task_address,
+                brush_flags | BrushFlags::PERSPECTIVE_INTERPOLATION | segment.brush_flags,
+                prim_header_index,
+                segment_data.specific_resource_address,
+            );
+        }
+    }
+
+    /// Add any segment(s) from a brush to batches.
+    ///
+    /// `edge_aa_mask` Specifies the edges that are *allowed* to have anti-aliasing, if and only
+    /// if the segments enable it.
+    /// In other words passing EdgeAaSegmentFlags::all() does not necessarily mean all edges will
+    /// be anti-aliased, only that they could be.
+    fn add_segmented_prim_to_batch(
+        &mut self,
+        brush_segments: Option<&[BrushSegment]>,
+        prim_opacity: PrimitiveOpacity,
+        params: &BrushBatchParameters,
+        blend_mode: BlendMode,
+        features: BatchFeatures,
+        brush_flags: BrushFlags,
+        edge_aa_mask: EdgeAaSegmentMask,
+        prim_header_index: PrimitiveHeaderIndex,
+        bounding_rect: &PictureRect,
+        transform_kind: TransformedRectKind,
+        z_id: ZBufferId,
+        clip_task_index: ClipTaskIndex,
+        ctx: &RenderTargetContext,
+        render_tasks: &RenderTaskGraph,
+    ) {
+        match (brush_segments, &params.segment_data) {
+            (Some(ref brush_segments), SegmentDataKind::Instanced(ref segment_data)) => {
+                // In this case, we have both a list of segments, and a list of
+                // per-segment instance data. Zip them together to build batches.
+                debug_assert_eq!(brush_segments.len(), segment_data.len());
+                for (segment_index, (segment, segment_data)) in brush_segments
+                    .iter()
+                    .zip(segment_data.iter())
+                    .enumerate()
+                {
+                    self.add_segment_to_batch(
+                        segment,
+                        segment_data,
+                        segment_index as i32,
+                        params.batch_kind,
+                        prim_header_index,
+                        blend_mode,
+                        features,
+                        brush_flags,
+                        edge_aa_mask,
+                        bounding_rect,
+                        transform_kind,
+                        z_id,
+                        prim_opacity,
+                        clip_task_index,
+                        ctx,
+                        render_tasks,
+                    );
+                }
+            }
+            (Some(ref brush_segments), SegmentDataKind::Shared(ref segment_data)) => {
+                // A list of segments, but the per-segment data is common
+                // between all segments.
+                for (segment_index, segment) in brush_segments
+                    .iter()
+                    .enumerate()
+                {
+                    self.add_segment_to_batch(
+                        segment,
+                        segment_data,
+                        segment_index as i32,
+                        params.batch_kind,
+                        prim_header_index,
+                        blend_mode,
+                        features,
+                        brush_flags,
+                        edge_aa_mask,
+                        bounding_rect,
+                        transform_kind,
+                        z_id,
+                        prim_opacity,
+                        clip_task_index,
+                        ctx,
+                        render_tasks,
+                    );
+                }
+            }
+            (None, SegmentDataKind::Shared(ref segment_data)) => {
+                // No segments, and thus no per-segment instance data.
+                // Note: the blend mode already takes opacity into account
+
+                let (clip_task_address, clip_mask) = ctx.get_prim_clip_task_and_texture(
+                    clip_task_index,
+                    render_tasks,
+                ).unwrap();
+
+                let textures = BatchTextures {
+                    input: segment_data.textures,
+                    clip_mask,
+                };
+
+                let batch_key = BatchKey {
+                    blend_mode,
+                    kind: BatchKind::Brush(params.batch_kind),
+                    textures,
+                };
+
+                self.add_brush_instance_to_batches(
+                    batch_key,
+                    features,
+                    bounding_rect,
+                    z_id,
+                    INVALID_SEGMENT_INDEX,
+                    edge_aa_mask,
+                    clip_task_address,
+                    brush_flags | BrushFlags::PERSPECTIVE_INTERPOLATION,
+                    prim_header_index,
+                    segment_data.specific_resource_address,
+                );
+            }
+            (None, SegmentDataKind::Instanced(..)) => {
+                // We should never hit the case where there are no segments,
+                // but a list of segment instance data.
+                unreachable!();
+            }
+        }
+    }
+}
+
+/// Either a single texture / user data for all segments,
+/// or a list of one per segment.
+enum SegmentDataKind {
+    Shared(SegmentInstanceData),
+    Instanced(SmallVec<[SegmentInstanceData; 8]>),
+}
+
+/// The parameters that are specific to a kind of brush,
+/// used by the common method to add a brush to batches.
+struct BrushBatchParameters {
+    batch_kind: BrushBatchKind,
+    prim_user_data: [i32; 4],
+    segment_data: SegmentDataKind,
+}
+
+impl BrushBatchParameters {
+    /// This brush instance has a list of per-segment
+    /// instance data.
+    fn instanced(
+        batch_kind: BrushBatchKind,
+        prim_user_data: [i32; 4],
+        segment_data: SmallVec<[SegmentInstanceData; 8]>,
+    ) -> Self {
+        BrushBatchParameters {
+            batch_kind,
+            prim_user_data,
+            segment_data: SegmentDataKind::Instanced(segment_data),
+        }
+    }
+
+    /// This brush instance shares the per-segment data
+    /// across all segments.
+    fn shared(
+        batch_kind: BrushBatchKind,
+        textures: TextureSet,
+        prim_user_data: [i32; 4],
+        specific_resource_address: i32,
+    ) -> Self {
+        BrushBatchParameters {
+            batch_kind,
+            prim_user_data,
+            segment_data: SegmentDataKind::Shared(
+                SegmentInstanceData {
+                    textures,
+                    specific_resource_address,
+                }
+            ),
+        }
+    }
+}
+
+/// A list of clip instances to be drawn into a target.
+#[derive(Debug)]
+#[cfg_attr(feature = "capture", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
+pub struct ClipBatchList {
+    /// Rectangle draws fill up the rectangles with rounded corners.
+    pub slow_rectangles: Vec<ClipMaskInstanceRect>,
+    pub fast_rectangles: Vec<ClipMaskInstanceRect>,
+    /// Image draws apply the image masking.
+    pub images: FastHashMap<(TextureSource, Option<DeviceIntRect>), Vec<ClipMaskInstanceImage>>,
+    pub box_shadows: FastHashMap<TextureSource, Vec<ClipMaskInstanceBoxShadow>>,
+}
+
+impl ClipBatchList {
+    fn new() -> Self {
+        ClipBatchList {
+            slow_rectangles: Vec::new(),
+            fast_rectangles: Vec::new(),
+            images: FastHashMap::default(),
+            box_shadows: FastHashMap::default(),
+        }
+    }
+}
+
+/// Batcher managing draw calls into the clip mask (in the RT cache).
+#[derive(Debug)]
+#[cfg_attr(feature = "capture", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
+pub struct ClipBatcher {
+    /// The first clip in each clip task. This will overwrite all pixels
+    /// in the clip region, so we can skip doing a clear and write with
+    /// blending disabled, which is a big performance win on Intel GPUs.
+    pub primary_clips: ClipBatchList,
+    /// Any subsequent clip masks (rare) for a clip task get drawn in
+    /// a second pass with multiplicative blending enabled.
+    pub secondary_clips: ClipBatchList,
+
+    gpu_supports_fast_clears: bool,
+}
+
+impl ClipBatcher {
+    pub fn new(
+        gpu_supports_fast_clears: bool,
+    ) -> Self {
+        ClipBatcher {
+            primary_clips: ClipBatchList::new(),
+            secondary_clips: ClipBatchList::new(),
+            gpu_supports_fast_clears,
+        }
+    }
+
+    pub fn add_clip_region(
+        &mut self,
+        local_pos: LayoutPoint,
+        sub_rect: DeviceRect,
+        clip_data: ClipData,
+        task_origin: DevicePoint,
+        screen_origin: DevicePoint,
+        device_pixel_scale: f32,
+    ) {
+        let instance = ClipMaskInstanceRect {
+            common: ClipMaskInstanceCommon {
+                clip_transform_id: TransformPaletteId::IDENTITY,
+                prim_transform_id: TransformPaletteId::IDENTITY,
+                sub_rect,
+                task_origin,
+                screen_origin,
+                device_pixel_scale,
+            },
+            local_pos,
+            clip_data,
+        };
+
+        self.primary_clips.slow_rectangles.push(instance);
+    }
+
+    /// Where appropriate, draw a clip rectangle as a small series of tiles,
+    /// instead of one large rectangle.
+    fn add_tiled_clip_mask(
+        &mut self,
+        mask_screen_rect: DeviceRect,
+        local_clip_rect: LayoutRect,
+        clip_spatial_node_index: SpatialNodeIndex,
+        spatial_tree: &SpatialTree,
+        world_rect: &WorldRect,
+        global_device_pixel_scale: DevicePixelScale,
+        common: &ClipMaskInstanceCommon,
+        is_first_clip: bool,
+    ) -> bool {
+        // Only try to draw in tiles if the clip mark is big enough.
+        if mask_screen_rect.area() < CLIP_RECTANGLE_AREA_THRESHOLD {
+            return false;
+        }
+
+        let mask_screen_rect_size = mask_screen_rect.size().to_i32();
+        let clip_spatial_node = spatial_tree.get_spatial_node(clip_spatial_node_index);
+
+        // Only support clips that are axis-aligned to the root coordinate space,
+        // for now, to simplify the logic below. This handles the vast majority
+        // of real world cases, but could be expanded in future if needed.
+        if clip_spatial_node.coordinate_system_id != CoordinateSystemId::root() {
+            return false;
+        }
+
+        // Get the world rect of the clip rectangle. If we can't transform it due
+        // to the matrix, just fall back to drawing the entire clip mask.
+        let transform = spatial_tree.get_world_transform(
+            clip_spatial_node_index,
+        );
+        let world_clip_rect = match project_rect(
+            &transform.into_transform(),
+            &local_clip_rect,
+            &world_rect,
+        ) {
+            Some(rect) => rect,
+            None => return false,
+        };
+
+        // Work out how many tiles to draw this clip mask in, stretched across the
+        // device rect of the primitive clip mask.
+        let world_device_rect = world_clip_rect * global_device_pixel_scale;
+        let x_tiles = (mask_screen_rect_size.width + CLIP_RECTANGLE_TILE_SIZE-1) / CLIP_RECTANGLE_TILE_SIZE;
+        let y_tiles = (mask_screen_rect_size.height + CLIP_RECTANGLE_TILE_SIZE-1) / CLIP_RECTANGLE_TILE_SIZE;
+
+        // Because we only run this code path for axis-aligned rects (the root coord system check above),
+        // and only for rectangles (not rounded etc), the world_device_rect is not conservative - we know
+        // that there is no inner_rect, and the world_device_rect should be the real, axis-aligned clip rect.
+        let mask_origin = mask_screen_rect.min.to_vector();
+        let clip_list = self.get_batch_list(is_first_clip);
+
+        for y in 0 .. y_tiles {
+            for x in 0 .. x_tiles {
+                let p0 = DeviceIntPoint::new(
+                    x * CLIP_RECTANGLE_TILE_SIZE,
+                    y * CLIP_RECTANGLE_TILE_SIZE,
+                );
+                let p1 = DeviceIntPoint::new(
+                    (p0.x + CLIP_RECTANGLE_TILE_SIZE).min(mask_screen_rect_size.width),
+                    (p0.y + CLIP_RECTANGLE_TILE_SIZE).min(mask_screen_rect_size.height),
+                );
+                let normalized_sub_rect = DeviceIntRect {
+                    min: p0,
+                    max: p1,
+                }.to_f32();
+                let world_sub_rect = normalized_sub_rect.translate(mask_origin);
+
+                // If the clip rect completely contains this tile rect, then drawing
+                // these pixels would be redundant - since this clip can't possibly
+                // affect the pixels in this tile, skip them!
+                if !world_device_rect.contains_box(&world_sub_rect) {
+                    clip_list.slow_rectangles.push(ClipMaskInstanceRect {
+                        common: ClipMaskInstanceCommon {
+                            sub_rect: normalized_sub_rect,
+                            ..*common
+                        },
+                        local_pos: local_clip_rect.min,
+                        clip_data: ClipData::uniform(local_clip_rect.size(), 0.0, ClipMode::Clip),
+                    });
+                }
+            }
+        }
+
+        true
+    }
+
+    /// Retrieve the correct clip batch list to append to, depending
+    /// on whether this is the first clip mask for a clip task.
+    fn get_batch_list(
+        &mut self,
+        is_first_clip: bool,
+    ) -> &mut ClipBatchList {
+        if is_first_clip && !self.gpu_supports_fast_clears {
+            &mut self.primary_clips
+        } else {
+            &mut self.secondary_clips
+        }
+    }
+
+    pub fn add(
+        &mut self,
+        clip_node_range: ClipNodeRange,
+        root_spatial_node_index: SpatialNodeIndex,
+        render_tasks: &RenderTaskGraph,
+        gpu_cache: &GpuCache,
+        clip_store: &ClipStore,
+        transforms: &mut TransformPalette,
+        actual_rect: DeviceRect,
+        surface_device_pixel_scale: DevicePixelScale,
+        task_origin: DevicePoint,
+        screen_origin: DevicePoint,
+        ctx: &RenderTargetContext,
+    ) -> bool {
+        let mut is_first_clip = true;
+        let mut clear_to_one = false;
+
+        for i in 0 .. clip_node_range.count {
+            let clip_instance = clip_store.get_instance_from_range(&clip_node_range, i);
+            let clip_node = &ctx.data_stores.clip[clip_instance.handle];
+
+            let clip_transform_id = transforms.get_id(
+                clip_node.item.spatial_node_index,
+                ctx.root_spatial_node_index,
+                ctx.spatial_tree,
+            );
+
+            // For clip mask images, we need to map from the primitive's layout space to
+            // the target space, as the cs_clip_image shader needs to forward transform
+            // the local image bounds, rather than backwards transform the target bounds
+            // as in done in write_clip_tile_vertex.
+            let prim_transform_id = match clip_node.item.kind {
+                ClipItemKind::Image { .. } => {
+                    transforms.get_id(
+                        clip_node.item.spatial_node_index,
+                        root_spatial_node_index,
+                        ctx.spatial_tree,
+                    )
+                }
+                _ => {
+                    transforms.get_id(
+                        root_spatial_node_index,
+                        ctx.root_spatial_node_index,
+                        ctx.spatial_tree,
+                    )
+                }
+            };
+
+            let common = ClipMaskInstanceCommon {
+                sub_rect: DeviceRect::from_size(actual_rect.size()),
+                task_origin,
+                screen_origin,
+                device_pixel_scale: surface_device_pixel_scale.0,
+                clip_transform_id,
+                prim_transform_id,
+            };
+
+            let added_clip = match clip_node.item.kind {
+                ClipItemKind::Image { image, rect, .. } => {
+                    let request = ImageRequest {
+                        key: image,
+                        rendering: ImageRendering::Auto,
+                        tile: None,
+                    };
+
+                    let map_local_to_raster = SpaceMapper::new_with_target(
+                        root_spatial_node_index,
+                        clip_node.item.spatial_node_index,
+                        WorldRect::max_rect(),
+                        ctx.spatial_tree,
+                    );
+
+                    let mut add_image = |request: ImageRequest, tile_rect: LayoutRect, sub_rect: DeviceRect| {
+                        let cache_item = match ctx.resource_cache.get_cached_image(request) {
+                            Ok(item) => item,
+                            Err(..) => {
+                                warn!("Warnings: skip a image mask");
+                                debug!("request: {:?}", request);
+                                return;
+                            }
+                        };
+
+                        // If the clip transform is axis-aligned, we can skip any need for scissoring
+                        // by clipping the local clip rect with the backwards transformed target bounds.
+                        // If it is not axis-aligned, then we pass the local clip rect through unmodified
+                        // to the shader and also set up a scissor rect for the overall target bounds to
+                        // ensure nothing is drawn outside the target. If for some reason we can't map the
+                        // rect back to local space, we also fall back to just using a scissor rectangle.
+                        let raster_rect =
+                            sub_rect.translate(actual_rect.min.to_vector()) / surface_device_pixel_scale;
+                        let (clip_transform_id, local_rect, scissor) = match map_local_to_raster.unmap(&raster_rect) {
+                            Some(local_rect)
+                                if clip_transform_id.transform_kind() == TransformedRectKind::AxisAligned &&
+                                   !map_local_to_raster.get_transform().has_perspective_component() => {
+                                    match local_rect.intersection(&rect) {
+                                        Some(local_rect) => (clip_transform_id, local_rect, None),
+                                        None => return,
+                                    }
+                            }
+                            _ => {
+                                // If for some reason inverting the transform failed, then don't consider
+                                // the transform to be axis-aligned if it was.
+                                (clip_transform_id.override_transform_kind(TransformedRectKind::Complex),
+                                 rect,
+                                 Some(common.sub_rect
+                                    .translate(task_origin.to_vector())
+                                    .round_out()
+                                    .to_i32()))
+                            }
+                        };
+
+                        self.get_batch_list(is_first_clip)
+                            .images
+                            .entry((cache_item.texture_id, scissor))
+                            .or_insert_with(Vec::new)
+                            .push(ClipMaskInstanceImage {
+                                common: ClipMaskInstanceCommon {
+                                    sub_rect,
+                                    clip_transform_id,
+                                    ..common
+                                },
+                                resource_address: gpu_cache.get_address(&cache_item.uv_rect_handle),
+                                tile_rect,
+                                local_rect,
+                            });
+                    };
+
+                    let clip_spatial_node = ctx.spatial_tree.get_spatial_node(clip_node.item.spatial_node_index);
+                    let clip_is_axis_aligned = clip_spatial_node.coordinate_system_id == CoordinateSystemId::root();
+
+                    if clip_instance.has_visible_tiles() {
+                        let sub_rect_bounds = actual_rect.size().into();
+
+                        for tile in clip_store.visible_mask_tiles(&clip_instance) {
+                            let tile_sub_rect = if clip_is_axis_aligned {
+                                let tile_raster_rect = map_local_to_raster
+                                    .map(&tile.tile_rect)
+                                    .expect("bug: should always map as axis-aligned");
+                                let tile_device_rect = tile_raster_rect * surface_device_pixel_scale;
+                                tile_device_rect
+                                    .translate(-actual_rect.min.to_vector())
+                                    .round_out()
+                                    .intersection(&sub_rect_bounds)
+                            } else {
+                                Some(common.sub_rect)
+                            };
+
+                            if let Some(tile_sub_rect) = tile_sub_rect {
+                                assert!(sub_rect_bounds.contains_box(&tile_sub_rect));
+                                add_image(
+                                    request.with_tile(tile.tile_offset),
+                                    tile.tile_rect,
+                                    tile_sub_rect,
+                                )
+                            }
+                        }
+                    } else {
+                        add_image(request, rect, common.sub_rect)
+                    }
+
+                    // If this is the first clip and either there is a transform or the image rect
+                    // doesn't cover the entire task, then request a clear so that pixels outside
+                    // the image boundaries will be properly initialized.
+                    if is_first_clip &&
+                        (!clip_is_axis_aligned ||
+                         !(map_local_to_raster.map(&rect).expect("bug: should always map as axis-aligned")
+                            * surface_device_pixel_scale).contains_box(&actual_rect)) {
+                        clear_to_one = true;
+                    }
+
+                    true
+                }
+                ClipItemKind::BoxShadow { ref source }  => {
+                    let task_id = source
+                        .render_task
+                        .expect("bug: render task handle not allocated");
+                    let (uv_rect_address, texture) = render_tasks.resolve_location(task_id, gpu_cache).unwrap();
+
+                    self.get_batch_list(is_first_clip)
+                        .box_shadows
+                        .entry(texture)
+                        .or_insert_with(Vec::new)
+                        .push(ClipMaskInstanceBoxShadow {
+                            common,
+                            resource_address: uv_rect_address,
+                            shadow_data: BoxShadowData {
+                                src_rect_size: source.original_alloc_size,
+                                clip_mode: source.clip_mode as i32,
+                                stretch_mode_x: source.stretch_mode_x as i32,
+                                stretch_mode_y: source.stretch_mode_y as i32,
+                                dest_rect: source.prim_shadow_rect,
+                            },
+                        });
+
+                    true
+                }
+                ClipItemKind::Rectangle { rect, mode: ClipMode::ClipOut } => {
+                    self.get_batch_list(is_first_clip)
+                        .slow_rectangles
+                        .push(ClipMaskInstanceRect {
+                            common,
+                            local_pos: rect.min,
+                            clip_data: ClipData::uniform(rect.size(), 0.0, ClipMode::ClipOut),
+                        });
+
+                    true
+                }
+                ClipItemKind::Rectangle { rect, mode: ClipMode::Clip } => {
+                    if clip_instance.flags.contains(ClipNodeFlags::SAME_COORD_SYSTEM) {
+                        false
+                    } else {
+                        if self.add_tiled_clip_mask(
+                            actual_rect,
+                            rect,
+                            clip_node.item.spatial_node_index,
+                            ctx.spatial_tree,
+                            &ctx.screen_world_rect,
+                            ctx.global_device_pixel_scale,
+                            &common,
+                            is_first_clip,
+                        ) {
+                            clear_to_one |= is_first_clip;
+                        } else {
+                            self.get_batch_list(is_first_clip)
+                                .slow_rectangles
+                                .push(ClipMaskInstanceRect {
+                                    common,
+                                    local_pos: rect.min,
+                                    clip_data: ClipData::uniform(rect.size(), 0.0, ClipMode::Clip),
+                                });
+                        }
+
+                        true
+                    }
+                }
+                ClipItemKind::RoundedRectangle { rect, ref radius, mode, .. } => {
+                    let batch_list = self.get_batch_list(is_first_clip);
+                    let instance = ClipMaskInstanceRect {
+                        common,
+                        local_pos: rect.min,
+                        clip_data: ClipData::rounded_rect(rect.size(), radius, mode),
+                    };
+                    if clip_instance.flags.contains(ClipNodeFlags::USE_FAST_PATH) {
+                        batch_list.fast_rectangles.push(instance);
+                    } else {
+                        batch_list.slow_rectangles.push(instance);
+                    }
+
+                    true
+                }
+            };
+
+            is_first_clip &= !added_clip;
+        }
+
+        clear_to_one
+    }
+}
+
+impl<'a, 'rc> RenderTargetContext<'a, 'rc> {
+    /// Retrieve the GPU task address for a given clip task instance.
+    /// Returns None if the segment was completely clipped out.
+    /// Returns Some(OPAQUE_TASK_ADDRESS) if no clip mask is needed.
+    /// Returns Some(task_address) if there was a valid clip mask.
+    fn get_clip_task_and_texture(
+        &self,
+        clip_task_index: ClipTaskIndex,
+        offset: i32,
+        render_tasks: &RenderTaskGraph,
+    ) -> Option<(RenderTaskAddress, TextureSource)> {
+        match self.scratch.clip_mask_instances[clip_task_index.0 as usize + offset as usize] {
+            ClipMaskKind::Mask(task_id) => {
+                Some((
+                    task_id.into(),
+                    TextureSource::TextureCache(
+                        render_tasks[task_id].get_target_texture(),
+                        Swizzle::default(),
+                    )
+                ))
+            }
+            ClipMaskKind::None => {
+                Some((OPAQUE_TASK_ADDRESS, TextureSource::Invalid))
+            }
+            ClipMaskKind::Clipped => {
+                None
+            }
+        }
+    }
+
+    /// Helper function to get the clip task address for a
+    /// non-segmented primitive.
+    fn get_prim_clip_task_and_texture(
+        &self,
+        clip_task_index: ClipTaskIndex,
+        render_tasks: &RenderTaskGraph,
+    ) -> Option<(RenderTaskAddress, TextureSource)> {
+        self.get_clip_task_and_texture(
+            clip_task_index,
+            0,
+            render_tasks,
+        )
+    }
+}
+
+pub fn add_quad_to_batch<F>(
+    render_task_address: RenderTaskAddress,
+    transform_id: TransformPaletteId,
+    gpu_buffer_address: GpuBufferAddress,
+    quad_flags: QuadFlags,
+    edge_flags: EdgeAaSegmentMask,
+    segment_index: u8,
+    task_id: RenderTaskId,
+    z_id: ZBufferId,
+    render_tasks: &RenderTaskGraph,
+    mut f: F,
+) where F: FnMut(BatchKey, PrimitiveInstanceData) {
+
+    #[repr(u8)]
+    enum PartIndex {
+        Center = 0,
+        Left = 1,
+        Top = 2,
+        Right = 3,
+        Bottom = 4,
+    }
+
+    let texture = match task_id {
+        RenderTaskId::INVALID => {
+            TextureSource::Invalid
+        }
+        _ => {
+            let texture = render_tasks
+                .resolve_texture(task_id)
+                .expect("bug: valid task id must be resolvable");
+
+            texture
+        }
+    };
+
+    let textures = BatchTextures::prim_textured(
+        texture,
+        TextureSource::Invalid,
+    );
+
+    let default_blend_mode = if quad_flags.contains(QuadFlags::IS_OPAQUE) && task_id == RenderTaskId::INVALID {
+        BlendMode::None
+    } else {
+        BlendMode::PremultipliedAlpha
+    };
+
+    let inner_batch_key = BatchKey {
+        blend_mode: default_blend_mode,
+        kind: BatchKind::Primitive,
+        textures,
+    };
+
+    let edge_batch_key = BatchKey {
+        blend_mode: BlendMode::PremultipliedAlpha,
+        kind: BatchKind::Primitive,
+        textures,
+    };
+
+    let edge_flags_bits = edge_flags.bits();
+
+    let main_instance = QuadInstance {
+        render_task_address,
+        prim_address: gpu_buffer_address,
+        z_id,
+        transform_id,
+        edge_flags: edge_flags_bits,
+        quad_flags: quad_flags.bits(),
+        part_index: PartIndex::Center as u8,
+        segment_index,
+    };
+
+    if edge_flags.contains(EdgeAaSegmentMask::LEFT) {
+        let instance = QuadInstance {
+            part_index: PartIndex::Left as u8,
+            ..main_instance
+        };
+        f(edge_batch_key, instance.into());
+    }
+    if edge_flags.contains(EdgeAaSegmentMask::RIGHT) {
+        let instance = QuadInstance {
+            part_index: PartIndex::Top as u8,
+            ..main_instance
+        };
+        f(edge_batch_key, instance.into());
+    }
+    if edge_flags.contains(EdgeAaSegmentMask::TOP) {
+        let instance = QuadInstance {
+            part_index: PartIndex::Right as u8,
+            ..main_instance
+        };
+        f(edge_batch_key, instance.into());
+    }
+    if edge_flags.contains(EdgeAaSegmentMask::BOTTOM) {
+        let instance = QuadInstance {
+            part_index: PartIndex::Bottom as u8,
+            ..main_instance
+        };
+        f(edge_batch_key, instance.into());
+    }
+
+    let instance = QuadInstance {
+        ..main_instance
+    };
+    f(inner_batch_key, instance.into());
+}