Adding upstream version 115.7.0esr.upstream/115.7.0esr

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

1 files changed, 1473 insertions, 0 deletions

diff --git a/gfx/wr/webrender/src/border.rs b/gfx/wr/webrender/src/border.rs
new file mode 100644
index 0000000000..d811f5edc2
--- /dev/null
+++ b/gfx/wr/webrender/src/border.rs
@@ -0,0 +1,1473 @@
+/* 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::{BorderRadius, BorderSide, BorderStyle, ColorF, ColorU};
+use api::{NormalBorder as ApiNormalBorder, RepeatMode};
+use api::units::*;
+use crate::clip::ClipNodeId;
+use crate::ellipse::Ellipse;
+use euclid::vec2;
+use crate::scene_building::SceneBuilder;
+use crate::spatial_tree::SpatialNodeIndex;
+use crate::gpu_types::{BorderInstance, BorderSegment, BrushFlags};
+use crate::prim_store::{BorderSegmentInfo, BrushSegment, NinePatchDescriptor};
+use crate::prim_store::borders::{NormalBorderPrim, NormalBorderData};
+use crate::util::{lerp, RectHelpers};
+use crate::internal_types::LayoutPrimitiveInfo;
+use crate::segment::EdgeAaSegmentMask;
+
+// Using 2048 as the maximum radius in device space before which we
+// start stretching is up for debate.
+// the value must be chosen so that the corners will not use an
+// unreasonable amount of memory but should allow crisp corners in the
+// common cases.
+
+/// Maximum resolution in device pixels at which borders are rasterized.
+pub const MAX_BORDER_RESOLUTION: u32 = 2048;
+/// Maximum number of dots or dashes per segment to avoid freezing and filling up
+/// memory with unreasonable inputs. It would be better to address this by not building
+/// a list of per-dot information in the first place.
+pub const MAX_DASH_COUNT: u32 = 2048;
+
+// TODO(gw): Perhaps there is a better way to store
+//           the border cache key than duplicating
+//           all the border structs with hashable
+//           variants...
+
+#[derive(Copy, Clone, Debug, Hash, MallocSizeOf, PartialEq, Eq)]
+#[cfg_attr(feature = "capture", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
+pub struct BorderRadiusAu {
+    pub top_left: LayoutSizeAu,
+    pub top_right: LayoutSizeAu,
+    pub bottom_left: LayoutSizeAu,
+    pub bottom_right: LayoutSizeAu,
+}
+
+impl From<BorderRadius> for BorderRadiusAu {
+    fn from(radius: BorderRadius) -> BorderRadiusAu {
+        BorderRadiusAu {
+            top_left: radius.top_left.to_au(),
+            top_right: radius.top_right.to_au(),
+            bottom_right: radius.bottom_right.to_au(),
+            bottom_left: radius.bottom_left.to_au(),
+        }
+    }
+}
+
+impl From<BorderRadiusAu> for BorderRadius {
+    fn from(radius: BorderRadiusAu) -> Self {
+        BorderRadius {
+            top_left: LayoutSize::from_au(radius.top_left),
+            top_right: LayoutSize::from_au(radius.top_right),
+            bottom_right: LayoutSize::from_au(radius.bottom_right),
+            bottom_left: LayoutSize::from_au(radius.bottom_left),
+        }
+    }
+}
+
+#[derive(Clone, Debug, Hash, MallocSizeOf, PartialEq, Eq)]
+#[cfg_attr(feature = "capture", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
+pub struct BorderSideAu {
+    pub color: ColorU,
+    pub style: BorderStyle,
+}
+
+impl From<BorderSide> for BorderSideAu {
+    fn from(side: BorderSide) -> Self {
+        BorderSideAu {
+            color: side.color.into(),
+            style: side.style,
+        }
+    }
+}
+
+impl From<BorderSideAu> for BorderSide {
+    fn from(side: BorderSideAu) -> Self {
+        BorderSide {
+            color: side.color.into(),
+            style: side.style,
+        }
+    }
+}
+
+#[cfg_attr(feature = "capture", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
+#[derive(Debug, Clone, Hash, Eq, MallocSizeOf, PartialEq)]
+pub struct NormalBorderAu {
+    pub left: BorderSideAu,
+    pub right: BorderSideAu,
+    pub top: BorderSideAu,
+    pub bottom: BorderSideAu,
+    pub radius: BorderRadiusAu,
+    /// Whether to apply anti-aliasing on the border corners.
+    ///
+    /// Note that for this to be `false` and work, this requires the borders to
+    /// be solid, and no border-radius.
+    pub do_aa: bool,
+}
+
+impl NormalBorderAu {
+    // Construct a border based upon self with color
+    pub fn with_color(&self, color: ColorU) -> Self {
+        let mut b = self.clone();
+        b.left.color = color;
+        b.right.color = color;
+        b.top.color = color;
+        b.bottom.color = color;
+        b
+    }
+}
+
+impl From<ApiNormalBorder> for NormalBorderAu {
+    fn from(border: ApiNormalBorder) -> Self {
+        NormalBorderAu {
+            left: border.left.into(),
+            right: border.right.into(),
+            top: border.top.into(),
+            bottom: border.bottom.into(),
+            radius: border.radius.into(),
+            do_aa: border.do_aa,
+        }
+    }
+}
+
+impl From<NormalBorderAu> for ApiNormalBorder {
+    fn from(border: NormalBorderAu) -> Self {
+        ApiNormalBorder {
+            left: border.left.into(),
+            right: border.right.into(),
+            top: border.top.into(),
+            bottom: border.bottom.into(),
+            radius: border.radius.into(),
+            do_aa: border.do_aa,
+        }
+    }
+}
+
+/// Cache key that uniquely identifies a border
+/// segment in the render task cache.
+#[derive(Clone, Debug, Hash, MallocSizeOf, PartialEq, Eq)]
+#[cfg_attr(feature = "capture", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
+pub struct BorderSegmentCacheKey {
+    pub size: LayoutSizeAu,
+    pub radius: LayoutSizeAu,
+    pub side0: BorderSideAu,
+    pub side1: BorderSideAu,
+    pub segment: BorderSegment,
+    pub do_aa: bool,
+    pub h_adjacent_corner_outer: LayoutPointAu,
+    pub h_adjacent_corner_radius: LayoutSizeAu,
+    pub v_adjacent_corner_outer: LayoutPointAu,
+    pub v_adjacent_corner_radius: LayoutSizeAu,
+}
+
+pub fn ensure_no_corner_overlap(
+    radius: &mut BorderRadius,
+    size: LayoutSize,
+) {
+    let mut ratio = 1.0;
+    let top_left_radius = &mut radius.top_left;
+    let top_right_radius = &mut radius.top_right;
+    let bottom_right_radius = &mut radius.bottom_right;
+    let bottom_left_radius = &mut radius.bottom_left;
+
+    let sum = top_left_radius.width + top_right_radius.width;
+    if size.width < sum {
+        ratio = f32::min(ratio, size.width / sum);
+    }
+
+    let sum = bottom_left_radius.width + bottom_right_radius.width;
+    if size.width < sum {
+        ratio = f32::min(ratio, size.width / sum);
+    }
+
+    let sum = top_left_radius.height + bottom_left_radius.height;
+    if size.height < sum {
+        ratio = f32::min(ratio, size.height / sum);
+    }
+
+    let sum = top_right_radius.height + bottom_right_radius.height;
+    if size.height < sum {
+        ratio = f32::min(ratio, size.height / sum);
+    }
+
+    if ratio < 1. {
+        top_left_radius.width *= ratio;
+        top_left_radius.height *= ratio;
+
+        top_right_radius.width *= ratio;
+        top_right_radius.height *= ratio;
+
+        bottom_left_radius.width *= ratio;
+        bottom_left_radius.height *= ratio;
+
+        bottom_right_radius.width *= ratio;
+        bottom_right_radius.height *= ratio;
+    }
+}
+
+impl<'a> SceneBuilder<'a> {
+    pub fn add_normal_border(
+        &mut self,
+        info: &LayoutPrimitiveInfo,
+        border: &ApiNormalBorder,
+        widths: LayoutSideOffsets,
+        spatial_node_index: SpatialNodeIndex,
+        clip_node_id: ClipNodeId,
+    ) {
+        let mut border = *border;
+        ensure_no_corner_overlap(&mut border.radius, info.rect.size());
+
+        self.add_primitive(
+            spatial_node_index,
+            clip_node_id,
+            info,
+            Vec::new(),
+            NormalBorderPrim {
+                border: border.into(),
+                widths: widths.to_au(),
+            },
+        );
+    }
+}
+
+pub trait BorderSideHelpers {
+    fn border_color(&self, is_inner_border: bool) -> ColorF;
+}
+
+impl BorderSideHelpers for BorderSide {
+    fn border_color(&self, is_inner_border: bool) -> ColorF {
+        let lighter = match self.style {
+            BorderStyle::Inset => is_inner_border,
+            BorderStyle::Outset => !is_inner_border,
+            _ => return self.color,
+        };
+
+        // The modulate colors below are not part of the specification. They are
+        // derived from the Gecko source code and experimentation, and used to
+        // modulate the colors in order to generate colors for the inset/outset
+        // and groove/ridge border styles.
+        //
+        // NOTE(emilio): Gecko at least takes the background color into
+        // account, should we do the same? Looks a bit annoying for this.
+        //
+        // NOTE(emilio): If you change this algorithm, do the same change on
+        // get_colors_for_side in cs_border_segment.glsl.
+        if self.color.r != 0.0 || self.color.g != 0.0 || self.color.b != 0.0 {
+            let scale = if lighter { 1.0 } else { 2.0 / 3.0 };
+            return self.color.scale_rgb(scale)
+        }
+
+        let black = if lighter { 0.7 } else { 0.3 };
+        ColorF::new(black, black, black, self.color.a)
+    }
+}
+
+/// The kind of border corner clip.
+#[repr(C)]
+#[derive(Copy, Debug, Clone, PartialEq)]
+pub enum BorderClipKind {
+    DashCorner = 1,
+    DashEdge = 2,
+    Dot = 3,
+}
+
+fn compute_outer_and_clip_sign(
+    corner_segment: BorderSegment,
+    radius: DeviceSize,
+) -> (DevicePoint, DeviceVector2D) {
+    let outer_scale = match corner_segment {
+        BorderSegment::TopLeft => DeviceVector2D::new(0.0, 0.0),
+        BorderSegment::TopRight => DeviceVector2D::new(1.0, 0.0),
+        BorderSegment::BottomRight => DeviceVector2D::new(1.0, 1.0),
+        BorderSegment::BottomLeft => DeviceVector2D::new(0.0, 1.0),
+        _ => panic!("bug: expected a corner segment"),
+    };
+    let outer = DevicePoint::new(
+        outer_scale.x * radius.width,
+        outer_scale.y * radius.height,
+    );
+
+    let clip_sign = DeviceVector2D::new(
+        1.0 - 2.0 * outer_scale.x,
+        1.0 - 2.0 * outer_scale.y,
+    );
+
+    (outer, clip_sign)
+}
+
+fn write_dashed_corner_instances(
+    corner_radius: DeviceSize,
+    widths: DeviceSize,
+    segment: BorderSegment,
+    base_instance: &BorderInstance,
+    instances: &mut Vec<BorderInstance>,
+) -> Result<(), ()> {
+    let ellipse = Ellipse::new(corner_radius);
+
+    let average_border_width = 0.5 * (widths.width + widths.height);
+
+    let (_half_dash, num_half_dashes) =
+        compute_half_dash(average_border_width, ellipse.total_arc_length);
+
+    if num_half_dashes == 0 {
+        return Err(());
+    }
+
+    let num_half_dashes = num_half_dashes.min(MAX_DASH_COUNT);
+
+    let (outer, clip_sign) = compute_outer_and_clip_sign(segment, corner_radius);
+
+    let instance_count = num_half_dashes / 4 + 1;
+    instances.reserve(instance_count as usize);
+
+    let half_dash_arc_length =
+        ellipse.total_arc_length / num_half_dashes as f32;
+    let dash_length = 2. * half_dash_arc_length;
+
+    let mut current_length = 0.;
+    for i in 0..instance_count {
+        let arc_length0 = current_length;
+        current_length += if i == 0 {
+            half_dash_arc_length
+        } else {
+            dash_length
+        };
+
+        let arc_length1 = current_length;
+        current_length += dash_length;
+
+        let alpha = ellipse.find_angle_for_arc_length(arc_length0);
+        let beta = ellipse.find_angle_for_arc_length(arc_length1);
+
+        let (point0, tangent0) = ellipse.get_point_and_tangent(alpha);
+        let (point1, tangent1) = ellipse.get_point_and_tangent(beta);
+
+        let point0 = DevicePoint::new(
+            outer.x + clip_sign.x * (corner_radius.width - point0.x),
+            outer.y + clip_sign.y * (corner_radius.height - point0.y),
+        );
+
+        let tangent0 = DeviceVector2D::new(
+            -tangent0.x * clip_sign.x,
+            -tangent0.y * clip_sign.y,
+        );
+
+        let point1 = DevicePoint::new(
+            outer.x + clip_sign.x * (corner_radius.width - point1.x),
+            outer.y + clip_sign.y * (corner_radius.height - point1.y),
+        );
+
+        let tangent1 = DeviceVector2D::new(
+            -tangent1.x * clip_sign.x,
+            -tangent1.y * clip_sign.y,
+        );
+
+        instances.push(BorderInstance {
+            flags: base_instance.flags | ((BorderClipKind::DashCorner as i32) << 24),
+            clip_params: [
+                point0.x,
+                point0.y,
+                tangent0.x,
+                tangent0.y,
+                point1.x,
+                point1.y,
+                tangent1.x,
+                tangent1.y,
+            ],
+            .. *base_instance
+        });
+    }
+
+    Ok(())
+}
+
+fn write_dotted_corner_instances(
+    corner_radius: DeviceSize,
+    widths: DeviceSize,
+    segment: BorderSegment,
+    base_instance: &BorderInstance,
+    instances: &mut Vec<BorderInstance>,
+) -> Result<(), ()> {
+    let mut corner_radius = corner_radius;
+    if corner_radius.width < (widths.width / 2.0) {
+        corner_radius.width = 0.0;
+    }
+    if corner_radius.height < (widths.height / 2.0) {
+        corner_radius.height = 0.0;
+    }
+
+    let (ellipse, max_dot_count) =
+        if corner_radius.width == 0. && corner_radius.height == 0. {
+            (Ellipse::new(corner_radius), 1)
+        } else {
+            // The centers of dots follow an ellipse along the middle of the
+            // border radius.
+            let inner_radius = (corner_radius - widths * 0.5).abs();
+            let ellipse = Ellipse::new(inner_radius);
+
+            // Allocate a "worst case" number of dot clips. This can be
+            // calculated by taking the minimum edge radius, since that
+            // will result in the maximum number of dots along the path.
+            let min_diameter = widths.width.min(widths.height);
+
+            // Get the number of circles (assuming spacing of one diameter
+            // between dots).
+            let max_dot_count = 0.5 * ellipse.total_arc_length / min_diameter;
+
+            // Add space for one extra dot since they are centered at the
+            // start of the arc.
+            (ellipse, max_dot_count.ceil() as usize)
+        };
+
+    if max_dot_count == 0 {
+        return Err(());
+    }
+
+    if max_dot_count == 1 {
+        let dot_diameter = lerp(widths.width, widths.height, 0.5);
+        instances.push(BorderInstance {
+            flags: base_instance.flags | ((BorderClipKind::Dot as i32) << 24),
+            clip_params: [
+                widths.width / 2.0, widths.height / 2.0, 0.5 * dot_diameter, 0.,
+                0., 0., 0., 0.,
+            ],
+            .. *base_instance
+        });
+        return Ok(());
+    }
+
+    let max_dot_count = max_dot_count.min(MAX_DASH_COUNT as usize);
+
+    // FIXME(emilio): Should probably use SmallVec.
+    let mut forward_dots = Vec::with_capacity(max_dot_count / 2 + 1);
+    let mut back_dots = Vec::with_capacity(max_dot_count / 2 + 1);
+    let mut leftover_arc_length = 0.0;
+
+    // Alternate between adding dots at the start and end of the
+    // ellipse arc. This ensures that we always end up with an exact
+    // half dot at each end of the arc, to match up with the edges.
+    forward_dots.push(DotInfo::new(widths.width, widths.width));
+    back_dots.push(DotInfo::new(
+        ellipse.total_arc_length - widths.height,
+        widths.height,
+    ));
+
+    let (outer, clip_sign) = compute_outer_and_clip_sign(segment, corner_radius);
+    for dot_index in 0 .. max_dot_count {
+        let prev_forward_pos = *forward_dots.last().unwrap();
+        let prev_back_pos = *back_dots.last().unwrap();
+
+        // Select which end of the arc to place a dot from.
+        // This just alternates between the start and end of
+        // the arc, which ensures that there is always an
+        // exact half-dot at each end of the ellipse.
+        let going_forward = dot_index & 1 == 0;
+
+        let (next_dot_pos, leftover) = if going_forward {
+            let next_dot_pos =
+                prev_forward_pos.arc_pos + 2.0 * prev_forward_pos.diameter;
+            (next_dot_pos, prev_back_pos.arc_pos - next_dot_pos)
+        } else {
+            let next_dot_pos = prev_back_pos.arc_pos - 2.0 * prev_back_pos.diameter;
+            (next_dot_pos, next_dot_pos - prev_forward_pos.arc_pos)
+        };
+
+        // Use a lerp between each edge's dot
+        // diameter, based on the linear distance
+        // along the arc to get the diameter of the
+        // dot at this arc position.
+        let t = next_dot_pos / ellipse.total_arc_length;
+        let dot_diameter = lerp(widths.width, widths.height, t);
+
+        // If we can't fit a dot, bail out.
+        if leftover < dot_diameter {
+            leftover_arc_length = leftover;
+            break;
+        }
+
+        // We can place a dot!
+        let dot = DotInfo::new(next_dot_pos, dot_diameter);
+        if going_forward {
+            forward_dots.push(dot);
+        } else {
+            back_dots.push(dot);
+        }
+    }
+
+    // Now step through the dots, and distribute any extra
+    // leftover space on the arc between them evenly. Once
+    // the final arc position is determined, generate the correct
+    // arc positions and angles that get passed to the clip shader.
+    let number_of_dots = forward_dots.len() + back_dots.len();
+    let extra_space_per_dot = leftover_arc_length / (number_of_dots - 1) as f32;
+
+    let create_dot_data = |arc_length: f32, dot_radius: f32| -> [f32; 8] {
+        // Represents the GPU data for drawing a single dot to a clip mask. The order
+        // these are specified must stay in sync with the way this data is read in the
+        // dot clip shader.
+        let theta = ellipse.find_angle_for_arc_length(arc_length);
+        let (center, _) = ellipse.get_point_and_tangent(theta);
+
+        let center = DevicePoint::new(
+            outer.x + clip_sign.x * (corner_radius.width - center.x),
+            outer.y + clip_sign.y * (corner_radius.height - center.y),
+        );
+
+        [center.x, center.y, dot_radius, 0.0, 0.0, 0.0, 0.0, 0.0]
+    };
+
+    instances.reserve(number_of_dots);
+    for (i, dot) in forward_dots.iter().enumerate() {
+        let extra_dist = i as f32 * extra_space_per_dot;
+        instances.push(BorderInstance {
+            flags: base_instance.flags | ((BorderClipKind::Dot as i32) << 24),
+            clip_params: create_dot_data(dot.arc_pos + extra_dist, 0.5 * dot.diameter),
+            .. *base_instance
+        });
+    }
+
+    for (i, dot) in back_dots.iter().enumerate() {
+        let extra_dist = i as f32 * extra_space_per_dot;
+        instances.push(BorderInstance {
+            flags: base_instance.flags | ((BorderClipKind::Dot as i32) << 24),
+            clip_params: create_dot_data(dot.arc_pos - extra_dist, 0.5 * dot.diameter),
+            .. *base_instance
+        });
+    }
+
+    Ok(())
+}
+
+#[derive(Copy, Clone, Debug)]
+struct DotInfo {
+    arc_pos: f32,
+    diameter: f32,
+}
+
+impl DotInfo {
+    fn new(arc_pos: f32, diameter: f32) -> DotInfo {
+        DotInfo { arc_pos, diameter }
+    }
+}
+
+/// Information needed to place and draw a border edge.
+#[derive(Debug)]
+struct EdgeInfo {
+    /// Offset in local space to place the edge from origin.
+    local_offset: f32,
+    /// Size of the edge in local space.
+    local_size: f32,
+    /// Local stretch size for this edge (repeat past this).
+    stretch_size: f32,
+}
+
+impl EdgeInfo {
+    fn new(
+        local_offset: f32,
+        local_size: f32,
+        stretch_size: f32,
+    ) -> Self {
+        Self {
+            local_offset,
+            local_size,
+            stretch_size,
+        }
+    }
+}
+
+// Given a side width and the available space, compute the half-dash (half of
+// the 'on' segment) and the count of them for a given segment.
+fn compute_half_dash(side_width: f32, total_size: f32) -> (f32, u32) {
+    let half_dash = side_width * 1.5;
+    let num_half_dashes = (total_size / half_dash).ceil() as u32;
+
+    if num_half_dashes == 0 {
+        return (0., 0);
+    }
+
+    // TODO(emilio): Gecko has some other heuristics here to start with a full
+    // dash when the border side is zero, for example. We might consider those
+    // in the future.
+    let num_half_dashes = if num_half_dashes % 4 != 0 {
+        num_half_dashes + 4 - num_half_dashes % 4
+    } else {
+        num_half_dashes
+    };
+
+    let half_dash = total_size / num_half_dashes as f32;
+    (half_dash, num_half_dashes)
+}
+
+
+// Get the needed size in device pixels for an edge,
+// based on the border style of that edge. This is used
+// to determine how big the render task should be.
+fn get_edge_info(
+    style: BorderStyle,
+    side_width: f32,
+    avail_size: f32,
+) -> EdgeInfo {
+    // To avoid division by zero below.
+    if side_width <= 0.0 || avail_size <= 0.0 {
+        return EdgeInfo::new(0.0, 0.0, 0.0);
+    }
+
+    match style {
+        BorderStyle::Dashed => {
+            // Basically, two times the dash size.
+            let (half_dash, _num_half_dashes) =
+                compute_half_dash(side_width, avail_size);
+            let stretch_size = 2.0 * 2.0 * half_dash;
+            EdgeInfo::new(0., avail_size, stretch_size)
+        }
+        BorderStyle::Dotted => {
+            let dot_and_space_size = 2.0 * side_width;
+            if avail_size < dot_and_space_size * 0.75 {
+                return EdgeInfo::new(0.0, 0.0, 0.0);
+            }
+            let approx_dot_count = avail_size / dot_and_space_size;
+            let dot_count = approx_dot_count.floor().max(1.0);
+            let used_size = dot_count * dot_and_space_size;
+            let extra_space = avail_size - used_size;
+            let stretch_size = dot_and_space_size;
+            let offset = (extra_space * 0.5).round();
+            EdgeInfo::new(offset, used_size, stretch_size)
+        }
+        _ => {
+            EdgeInfo::new(0.0, avail_size, 8.0)
+        }
+    }
+}
+
+/// Create the set of border segments and render task
+/// cache keys for a given CSS border.
+pub fn create_border_segments(
+    size: LayoutSize,
+    border: &ApiNormalBorder,
+    widths: &LayoutSideOffsets,
+    border_segments: &mut Vec<BorderSegmentInfo>,
+    brush_segments: &mut Vec<BrushSegment>,
+) {
+    let rect = LayoutRect::from_size(size);
+
+    let overlap = LayoutSize::new(
+        (widths.left + widths.right - size.width).max(0.0),
+        (widths.top + widths.bottom - size.height).max(0.0),
+    );
+    let non_overlapping_widths = LayoutSideOffsets::new(
+        widths.top - overlap.height / 2.0,
+        widths.right - overlap.width / 2.0,
+        widths.bottom - overlap.height / 2.0,
+        widths.left - overlap.width / 2.0,
+    );
+
+    let local_size_tl = LayoutSize::new(
+        border.radius.top_left.width.max(widths.left),
+        border.radius.top_left.height.max(widths.top),
+    );
+    let local_size_tr = LayoutSize::new(
+        border.radius.top_right.width.max(widths.right),
+        border.radius.top_right.height.max(widths.top),
+    );
+    let local_size_br = LayoutSize::new(
+        border.radius.bottom_right.width.max(widths.right),
+        border.radius.bottom_right.height.max(widths.bottom),
+    );
+    let local_size_bl = LayoutSize::new(
+        border.radius.bottom_left.width.max(widths.left),
+        border.radius.bottom_left.height.max(widths.bottom),
+    );
+
+    let top_edge_info = get_edge_info(
+        border.top.style,
+        widths.top,
+        rect.width() - local_size_tl.width - local_size_tr.width,
+    );
+    let bottom_edge_info = get_edge_info(
+        border.bottom.style,
+        widths.bottom,
+        rect.width() - local_size_bl.width - local_size_br.width,
+    );
+
+    let left_edge_info = get_edge_info(
+        border.left.style,
+        widths.left,
+        rect.height() - local_size_tl.height - local_size_bl.height,
+    );
+    let right_edge_info = get_edge_info(
+        border.right.style,
+        widths.right,
+        rect.height() - local_size_tr.height - local_size_br.height,
+    );
+
+    add_edge_segment(
+        LayoutRect::from_floats(
+            rect.min.x,
+            rect.min.y + local_size_tl.height + left_edge_info.local_offset,
+            rect.min.x + non_overlapping_widths.left,
+            rect.min.y + local_size_tl.height + left_edge_info.local_offset + left_edge_info.local_size,
+        ),
+        &left_edge_info,
+        border.left,
+        non_overlapping_widths.left,
+        BorderSegment::Left,
+        EdgeAaSegmentMask::LEFT | EdgeAaSegmentMask::RIGHT,
+        brush_segments,
+        border_segments,
+        border.do_aa,
+    );
+    add_edge_segment(
+        LayoutRect::from_floats(
+            rect.min.x + local_size_tl.width + top_edge_info.local_offset,
+            rect.min.y,
+            rect.min.x + local_size_tl.width + top_edge_info.local_offset + top_edge_info.local_size,
+            rect.min.y + non_overlapping_widths.top,
+        ),
+        &top_edge_info,
+        border.top,
+        non_overlapping_widths.top,
+        BorderSegment::Top,
+        EdgeAaSegmentMask::TOP | EdgeAaSegmentMask::BOTTOM,
+        brush_segments,
+        border_segments,
+        border.do_aa,
+    );
+    add_edge_segment(
+        LayoutRect::from_floats(
+            rect.min.x + rect.width() - non_overlapping_widths.right,
+            rect.min.y + local_size_tr.height + right_edge_info.local_offset,
+            rect.min.x + rect.width(),
+            rect.min.y + local_size_tr.height + right_edge_info.local_offset + right_edge_info.local_size,
+        ),
+        &right_edge_info,
+        border.right,
+        non_overlapping_widths.right,
+        BorderSegment::Right,
+        EdgeAaSegmentMask::RIGHT | EdgeAaSegmentMask::LEFT,
+        brush_segments,
+        border_segments,
+        border.do_aa,
+    );
+    add_edge_segment(
+        LayoutRect::from_floats(
+            rect.min.x + local_size_bl.width + bottom_edge_info.local_offset,
+            rect.min.y + rect.height() - non_overlapping_widths.bottom,
+            rect.min.x + local_size_bl.width + bottom_edge_info.local_offset + bottom_edge_info.local_size,
+            rect.min.y + rect.height(),
+        ),
+        &bottom_edge_info,
+        border.bottom,
+        non_overlapping_widths.bottom,
+        BorderSegment::Bottom,
+        EdgeAaSegmentMask::BOTTOM | EdgeAaSegmentMask::TOP,
+        brush_segments,
+        border_segments,
+        border.do_aa,
+    );
+
+    add_corner_segment(
+        LayoutRect::from_floats(
+            rect.min.x,
+            rect.min.y,
+            rect.min.x + local_size_tl.width,
+            rect.min.y + local_size_tl.height,
+        ),
+        LayoutRect::from_floats(
+            rect.min.x,
+            rect.min.y,
+            rect.max.x - non_overlapping_widths.right,
+            rect.max.y - non_overlapping_widths.bottom
+        ),
+        border.left,
+        border.top,
+        LayoutSize::new(widths.left, widths.top),
+        border.radius.top_left,
+        BorderSegment::TopLeft,
+        EdgeAaSegmentMask::TOP | EdgeAaSegmentMask::LEFT,
+        rect.top_right(),
+        border.radius.top_right,
+        rect.bottom_left(),
+        border.radius.bottom_left,
+        brush_segments,
+        border_segments,
+        border.do_aa,
+    );
+    add_corner_segment(
+        LayoutRect::from_floats(
+            rect.min.x + rect.width() - local_size_tr.width,
+            rect.min.y,
+            rect.min.x + rect.width(),
+            rect.min.y + local_size_tr.height,
+        ),
+        LayoutRect::from_floats(
+            rect.min.x + non_overlapping_widths.left,
+            rect.min.y,
+            rect.max.x,
+            rect.max.y - non_overlapping_widths.bottom,
+        ),
+        border.top,
+        border.right,
+        LayoutSize::new(widths.right, widths.top),
+        border.radius.top_right,
+        BorderSegment::TopRight,
+        EdgeAaSegmentMask::TOP | EdgeAaSegmentMask::RIGHT,
+        rect.min,
+        border.radius.top_left,
+        rect.max,
+        border.radius.bottom_right,
+        brush_segments,
+        border_segments,
+        border.do_aa,
+    );
+    add_corner_segment(
+        LayoutRect::from_floats(
+            rect.min.x + rect.width() - local_size_br.width,
+            rect.min.y + rect.height() - local_size_br.height,
+            rect.min.x + rect.width(),
+            rect.min.y + rect.height(),
+        ),
+        LayoutRect::from_floats(
+            rect.min.x + non_overlapping_widths.left,
+            rect.min.y + non_overlapping_widths.top,
+            rect.max.x,
+            rect.max.y,
+        ),
+        border.right,
+        border.bottom,
+        LayoutSize::new(widths.right, widths.bottom),
+        border.radius.bottom_right,
+        BorderSegment::BottomRight,
+        EdgeAaSegmentMask::BOTTOM | EdgeAaSegmentMask::RIGHT,
+        rect.bottom_left(),
+        border.radius.bottom_left,
+        rect.top_right(),
+        border.radius.top_right,
+        brush_segments,
+        border_segments,
+        border.do_aa,
+    );
+    add_corner_segment(
+        LayoutRect::from_floats(
+            rect.min.x,
+            rect.min.y + rect.height() - local_size_bl.height,
+            rect.min.x + local_size_bl.width,
+            rect.min.y + rect.height(),
+        ),
+        LayoutRect::from_floats(
+            rect.min.x,
+            rect.min.y + non_overlapping_widths.top,
+            rect.max.x - non_overlapping_widths.right,
+            rect.max.y,
+        ),
+        border.bottom,
+        border.left,
+        LayoutSize::new(widths.left, widths.bottom),
+        border.radius.bottom_left,
+        BorderSegment::BottomLeft,
+        EdgeAaSegmentMask::BOTTOM | EdgeAaSegmentMask::LEFT,
+        rect.max,
+        border.radius.bottom_right,
+        rect.min,
+        border.radius.top_left,
+        brush_segments,
+        border_segments,
+        border.do_aa,
+    );
+}
+
+/// Computes the maximum scale that we allow for this set of border parameters.
+/// capping the scale will result in rendering very large corners at a lower
+/// resolution and stretching them, so they will have the right shape, but
+/// blurrier.
+pub fn get_max_scale_for_border(
+    border_data: &NormalBorderData,
+) -> LayoutToDeviceScale {
+    let mut r = 1.0;
+    for segment in &border_data.border_segments {
+        let size = segment.local_task_size;
+        r = size.width.max(size.height.max(r));
+    }
+
+    LayoutToDeviceScale::new(MAX_BORDER_RESOLUTION as f32 / r)
+}
+
+fn add_segment(
+    task_rect: DeviceRect,
+    style0: BorderStyle,
+    style1: BorderStyle,
+    color0: ColorF,
+    color1: ColorF,
+    segment: BorderSegment,
+    instances: &mut Vec<BorderInstance>,
+    widths: DeviceSize,
+    radius: DeviceSize,
+    do_aa: bool,
+    h_adjacent_corner_outer: DevicePoint,
+    h_adjacent_corner_radius: DeviceSize,
+    v_adjacent_corner_outer: DevicePoint,
+    v_adjacent_corner_radius: DeviceSize,
+) {
+    let base_flags = (segment as i32) |
+                     ((style0 as i32) << 8) |
+                     ((style1 as i32) << 16) |
+                     ((do_aa as i32) << 28);
+
+    let base_instance = BorderInstance {
+        task_origin: DevicePoint::zero(),
+        local_rect: task_rect,
+        flags: base_flags,
+        color0: color0.premultiplied(),
+        color1: color1.premultiplied(),
+        widths,
+        radius,
+        clip_params: [0.0; 8],
+    };
+
+    match segment {
+        BorderSegment::TopLeft |
+        BorderSegment::TopRight |
+        BorderSegment::BottomLeft |
+        BorderSegment::BottomRight => {
+            // TODO(gw): Similarly to the old border code, we don't correctly handle a a corner
+            //           that is dashed on one edge, and dotted on another. We can handle this
+            //           in the future by submitting two instances, each one with one side
+            //           color set to have an alpha of 0.
+            if (style0 == BorderStyle::Dotted && style1 == BorderStyle::Dashed) ||
+               (style0 == BorderStyle::Dashed && style0 == BorderStyle::Dotted) {
+                warn!("TODO: Handle a corner with dotted / dashed transition.");
+            }
+
+            let dashed_or_dotted_corner = match style0 {
+                BorderStyle::Dashed => {
+                    write_dashed_corner_instances(
+                        radius,
+                        widths,
+                        segment,
+                        &base_instance,
+                        instances,
+                    )
+                }
+                BorderStyle::Dotted => {
+                    write_dotted_corner_instances(
+                        radius,
+                        widths,
+                        segment,
+                        &base_instance,
+                        instances,
+                    )
+                }
+                _ => Err(()),
+            };
+
+            if dashed_or_dotted_corner.is_err() {
+                let clip_params = [
+                    h_adjacent_corner_outer.x,
+                    h_adjacent_corner_outer.y,
+                    h_adjacent_corner_radius.width,
+                    h_adjacent_corner_radius.height,
+                    v_adjacent_corner_outer.x,
+                    v_adjacent_corner_outer.y,
+                    v_adjacent_corner_radius.width,
+                    v_adjacent_corner_radius.height,
+                ];
+
+                instances.push(BorderInstance {
+                    clip_params,
+                    ..base_instance
+                });
+            }
+        }
+        BorderSegment::Top |
+        BorderSegment::Bottom |
+        BorderSegment::Right |
+        BorderSegment::Left => {
+            let is_vertical = segment == BorderSegment::Left ||
+                              segment == BorderSegment::Right;
+
+            match style0 {
+                BorderStyle::Dashed => {
+                    let (x, y) = if is_vertical {
+                        let half_dash_size = task_rect.height() * 0.25;
+                        (0., half_dash_size)
+                    } else {
+                        let half_dash_size = task_rect.width() * 0.25;
+                        (half_dash_size, 0.)
+                    };
+
+                    instances.push(BorderInstance {
+                        flags: base_flags | ((BorderClipKind::DashEdge as i32) << 24),
+                        clip_params: [
+                            x, y, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
+                        ],
+                        ..base_instance
+                    });
+                }
+                BorderStyle::Dotted => {
+                    let (x, y, r) = if is_vertical {
+                        (widths.width * 0.5,
+                         widths.width,
+                         widths.width * 0.5)
+                    } else {
+                        (widths.height,
+                         widths.height * 0.5,
+                         widths.height * 0.5)
+                    };
+
+                    instances.push(BorderInstance {
+                        flags: base_flags | ((BorderClipKind::Dot as i32) << 24),
+                        clip_params: [
+                            x, y, r, 0.0, 0.0, 0.0, 0.0, 0.0,
+                        ],
+                        ..base_instance
+                    });
+                }
+                _ => {
+                    instances.push(base_instance);
+                }
+            }
+        }
+    }
+}
+
+/// Add a corner segment (if valid) to the list of
+/// border segments for this primitive.
+fn add_corner_segment(
+    image_rect: LayoutRect,
+    non_overlapping_rect: LayoutRect,
+    side0: BorderSide,
+    side1: BorderSide,
+    widths: LayoutSize,
+    radius: LayoutSize,
+    segment: BorderSegment,
+    edge_flags: EdgeAaSegmentMask,
+    h_adjacent_corner_outer: LayoutPoint,
+    h_adjacent_corner_radius: LayoutSize,
+    v_adjacent_corner_outer: LayoutPoint,
+    v_adjacent_corner_radius: LayoutSize,
+    brush_segments: &mut Vec<BrushSegment>,
+    border_segments: &mut Vec<BorderSegmentInfo>,
+    do_aa: bool,
+) {
+    if side0.color.a <= 0.0 && side1.color.a <= 0.0 {
+        return;
+    }
+
+    if widths.width <= 0.0 && widths.height <= 0.0 {
+        return;
+    }
+
+    if side0.style.is_hidden() && side1.style.is_hidden() {
+        return;
+    }
+
+    let segment_rect = match image_rect.intersection(&non_overlapping_rect) {
+        Some(rect) => rect,
+        None => {
+            return;
+        }
+    };
+
+    let texture_rect = segment_rect
+        .translate(-image_rect.min.to_vector())
+        .scale(1.0 / image_rect.width(), 1.0 / image_rect.height());
+
+    brush_segments.push(
+        BrushSegment::new(
+            segment_rect,
+            /* may_need_clip_mask = */ true,
+            edge_flags,
+            [texture_rect.min.x, texture_rect.min.y, texture_rect.max.x, texture_rect.max.y],
+            BrushFlags::SEGMENT_RELATIVE | BrushFlags::SEGMENT_TEXEL_RECT,
+        )
+    );
+
+    // If the radii of the adjacent corners do not overlap with this segment,
+    // then set the outer position to this segment's corner and the radii to zero.
+    // That way the cache key is unaffected by non-overlapping corners, resulting
+    // in fewer misses.
+    let (h_corner_outer, h_corner_radius) = match segment {
+        BorderSegment::TopLeft => {
+            if h_adjacent_corner_outer.x - h_adjacent_corner_radius.width < image_rect.max.x {
+                (h_adjacent_corner_outer, h_adjacent_corner_radius)
+            } else {
+                (LayoutPoint::new(image_rect.max.x, image_rect.min.y), LayoutSize::zero())
+            }
+        }
+        BorderSegment::TopRight => {
+            if h_adjacent_corner_outer.x + h_adjacent_corner_radius.width > image_rect.min.x {
+                (h_adjacent_corner_outer, h_adjacent_corner_radius)
+            } else {
+                (LayoutPoint::new(image_rect.min.x, image_rect.min.y), LayoutSize::zero())
+            }
+        }
+        BorderSegment::BottomRight => {
+            if h_adjacent_corner_outer.x + h_adjacent_corner_radius.width > image_rect.min.x {
+                (h_adjacent_corner_outer, h_adjacent_corner_radius)
+            } else {
+                (LayoutPoint::new(image_rect.min.x, image_rect.max.y), LayoutSize::zero())
+            }
+        }
+        BorderSegment::BottomLeft => {
+            if h_adjacent_corner_outer.x - h_adjacent_corner_radius.width < image_rect.max.x {
+                (h_adjacent_corner_outer, h_adjacent_corner_radius)
+            } else {
+                (image_rect.max, LayoutSize::zero())
+            }
+        }
+        _ => unreachable!()
+    };
+
+    let (v_corner_outer, v_corner_radius) = match segment {
+        BorderSegment::TopLeft => {
+            if v_adjacent_corner_outer.y - v_adjacent_corner_radius.height < image_rect.max.y {
+                (v_adjacent_corner_outer, v_adjacent_corner_radius)
+            } else {
+                (LayoutPoint::new(image_rect.min.x, image_rect.max.y), LayoutSize::zero())
+            }
+        }
+        BorderSegment::TopRight => {
+            if v_adjacent_corner_outer.y - v_adjacent_corner_radius.height < image_rect.max.y {
+                (v_adjacent_corner_outer, v_adjacent_corner_radius)
+            } else {
+                (image_rect.max, LayoutSize::zero())
+            }
+        }
+        BorderSegment::BottomRight => {
+            if v_adjacent_corner_outer.y + v_adjacent_corner_radius.height > image_rect.min.y {
+                (v_adjacent_corner_outer, v_adjacent_corner_radius)
+            } else {
+                (LayoutPoint::new(image_rect.max.x, image_rect.min.y), LayoutSize::zero())
+            }
+        }
+        BorderSegment::BottomLeft => {
+            if v_adjacent_corner_outer.y + v_adjacent_corner_radius.height > image_rect.min.y {
+                (v_adjacent_corner_outer, v_adjacent_corner_radius)
+            } else {
+                (LayoutPoint::new(image_rect.min.x, image_rect.min.y), LayoutSize::zero())
+            }
+        }
+        _ => unreachable!()
+    };
+
+    border_segments.push(BorderSegmentInfo {
+        local_task_size: image_rect.size(),
+        cache_key: BorderSegmentCacheKey {
+            do_aa,
+            side0: side0.into(),
+            side1: side1.into(),
+            segment,
+            radius: radius.to_au(),
+            size: widths.to_au(),
+            h_adjacent_corner_outer: (h_corner_outer - image_rect.min).to_point().to_au(),
+            h_adjacent_corner_radius: h_corner_radius.to_au(),
+            v_adjacent_corner_outer: (v_corner_outer - image_rect.min).to_point().to_au(),
+            v_adjacent_corner_radius: v_corner_radius.to_au(),
+        },
+    });
+}
+
+/// Add an edge segment (if valid) to the list of
+/// border segments for this primitive.
+fn add_edge_segment(
+    image_rect: LayoutRect,
+    edge_info: &EdgeInfo,
+    side: BorderSide,
+    width: f32,
+    segment: BorderSegment,
+    edge_flags: EdgeAaSegmentMask,
+    brush_segments: &mut Vec<BrushSegment>,
+    border_segments: &mut Vec<BorderSegmentInfo>,
+    do_aa: bool,
+) {
+    if side.color.a <= 0.0 {
+        return;
+    }
+
+    if side.style.is_hidden() {
+        return;
+    }
+
+    let (size, brush_flags) = match segment {
+        BorderSegment::Left | BorderSegment::Right => {
+            (LayoutSize::new(width, edge_info.stretch_size), BrushFlags::SEGMENT_REPEAT_Y)
+        }
+        BorderSegment::Top | BorderSegment::Bottom => {
+            (LayoutSize::new(edge_info.stretch_size, width), BrushFlags::SEGMENT_REPEAT_X)
+        }
+        _ => {
+            unreachable!();
+        }
+    };
+
+    if image_rect.width() <= 0. || image_rect.height() <= 0. {
+        return;
+    }
+
+    brush_segments.push(
+        BrushSegment::new(
+            image_rect,
+            /* may_need_clip_mask = */ true,
+            edge_flags,
+            [0.0, 0.0, size.width, size.height],
+            BrushFlags::SEGMENT_RELATIVE | brush_flags,
+        )
+    );
+
+    border_segments.push(BorderSegmentInfo {
+        local_task_size: size,
+        cache_key: BorderSegmentCacheKey {
+            do_aa,
+            side0: side.into(),
+            side1: side.into(),
+            radius: LayoutSizeAu::zero(),
+            size: size.to_au(),
+            segment,
+            h_adjacent_corner_outer: LayoutPointAu::zero(),
+            h_adjacent_corner_radius: LayoutSizeAu::zero(),
+            v_adjacent_corner_outer: LayoutPointAu::zero(),
+            v_adjacent_corner_radius: LayoutSizeAu::zero(),
+        },
+    });
+}
+
+/// Build the set of border instances needed to draw a border
+/// segment into the render task cache.
+pub fn build_border_instances(
+    cache_key: &BorderSegmentCacheKey,
+    cache_size: DeviceIntSize,
+    border: &ApiNormalBorder,
+    scale: LayoutToDeviceScale,
+) -> Vec<BorderInstance> {
+    let mut instances = Vec::new();
+
+    let (side0, side1, flip0, flip1) = match cache_key.segment {
+        BorderSegment::Left => (&border.left, &border.left, false, false),
+        BorderSegment::Top => (&border.top, &border.top, false, false),
+        BorderSegment::Right => (&border.right, &border.right, true, true),
+        BorderSegment::Bottom => (&border.bottom, &border.bottom, true, true),
+        BorderSegment::TopLeft => (&border.left, &border.top, false, false),
+        BorderSegment::TopRight => (&border.top, &border.right, false, true),
+        BorderSegment::BottomRight => (&border.right, &border.bottom, true, true),
+        BorderSegment::BottomLeft => (&border.bottom, &border.left, true, false),
+    };
+
+    let style0 = if side0.style.is_hidden() {
+        side1.style
+    } else {
+        side0.style
+    };
+    let style1 = if side1.style.is_hidden() {
+        side0.style
+    } else {
+        side1.style
+    };
+
+    let color0 = side0.border_color(flip0);
+    let color1 = side1.border_color(flip1);
+
+    let widths = (LayoutSize::from_au(cache_key.size) * scale).ceil();
+    let radius = (LayoutSize::from_au(cache_key.radius) * scale).ceil();
+
+    let h_corner_outer = (LayoutPoint::from_au(cache_key.h_adjacent_corner_outer) * scale).round();
+    let h_corner_radius = (LayoutSize::from_au(cache_key.h_adjacent_corner_radius) * scale).ceil();
+    let v_corner_outer = (LayoutPoint::from_au(cache_key.v_adjacent_corner_outer) * scale).round();
+    let v_corner_radius = (LayoutSize::from_au(cache_key.v_adjacent_corner_radius) * scale).ceil();
+
+    add_segment(
+        DeviceRect::from_size(cache_size.to_f32()),
+        style0,
+        style1,
+        color0,
+        color1,
+        cache_key.segment,
+        &mut instances,
+        widths,
+        radius,
+        border.do_aa,
+        h_corner_outer,
+        h_corner_radius,
+        v_corner_outer,
+        v_corner_radius,
+    );
+
+    instances
+}
+
+impl NinePatchDescriptor {
+    pub fn create_segments(
+        &self,
+        size: LayoutSize,
+    ) -> Vec<BrushSegment> {
+        let rect = LayoutRect::from_size(size);
+
+        // Calculate the local texel coords of the slices.
+        let px0 = 0.0;
+        let px1 = self.slice.left as f32 / self.width as f32;
+        let px2 = (self.width as f32 - self.slice.right as f32) / self.width as f32;
+        let px3 = 1.0;
+
+        let py0 = 0.0;
+        let py1 = self.slice.top as f32 / self.height as f32;
+        let py2 = (self.height as f32 - self.slice.bottom as f32) / self.height as f32;
+        let py3 = 1.0;
+
+        let tl_outer = LayoutPoint::new(rect.min.x, rect.min.y);
+        let tl_inner = tl_outer + vec2(self.widths.left, self.widths.top);
+
+        let tr_outer = LayoutPoint::new(rect.min.x + rect.width(), rect.min.y);
+        let tr_inner = tr_outer + vec2(-self.widths.right, self.widths.top);
+
+        let bl_outer = LayoutPoint::new(rect.min.x, rect.min.y + rect.height());
+        let bl_inner = bl_outer + vec2(self.widths.left, -self.widths.bottom);
+
+        let br_outer = rect.max;
+
+        let br_inner = br_outer - vec2(self.widths.right, self.widths.bottom);
+
+        fn add_segment(
+            segments: &mut Vec<BrushSegment>,
+            rect: LayoutRect,
+            uv_rect: TexelRect,
+            repeat_horizontal: RepeatMode,
+            repeat_vertical: RepeatMode,
+            extra_flags: BrushFlags,
+        ) {
+            if uv_rect.uv1.x <= uv_rect.uv0.x || uv_rect.uv1.y <= uv_rect.uv0.y {
+                return;
+            }
+
+            // Use segment relative interpolation for all
+            // instances in this primitive.
+            let mut brush_flags =
+                BrushFlags::SEGMENT_RELATIVE |
+                BrushFlags::SEGMENT_TEXEL_RECT |
+                extra_flags;
+
+            // Enable repeat modes on the segment.
+            if repeat_horizontal == RepeatMode::Repeat {
+                brush_flags |= BrushFlags::SEGMENT_REPEAT_X;
+            } else if repeat_horizontal == RepeatMode::Round {
+                brush_flags |= BrushFlags::SEGMENT_REPEAT_X | BrushFlags::SEGMENT_REPEAT_X_ROUND;
+            }
+
+            if repeat_vertical == RepeatMode::Repeat {
+                brush_flags |= BrushFlags::SEGMENT_REPEAT_Y;
+            } else if repeat_vertical == RepeatMode::Round {
+                brush_flags |= BrushFlags::SEGMENT_REPEAT_Y | BrushFlags::SEGMENT_REPEAT_Y_ROUND;
+            }
+
+            let segment = BrushSegment::new(
+                rect,
+                true,
+                EdgeAaSegmentMask::empty(),
+                [
+                    uv_rect.uv0.x,
+                    uv_rect.uv0.y,
+                    uv_rect.uv1.x,
+                    uv_rect.uv1.y,
+                ],
+                brush_flags,
+            );
+
+            segments.push(segment);
+        }
+
+        // Build the list of image segments
+        let mut segments = Vec::new();
+
+        // Top left
+        add_segment(
+            &mut segments,
+            LayoutRect::from_floats(tl_outer.x, tl_outer.y, tl_inner.x, tl_inner.y),
+            TexelRect::new(px0, py0, px1, py1),
+            RepeatMode::Stretch,
+            RepeatMode::Stretch,
+            BrushFlags::empty(),
+        );
+        // Top right
+        add_segment(
+            &mut segments,
+            LayoutRect::from_floats(tr_inner.x, tr_outer.y, tr_outer.x, tr_inner.y),
+            TexelRect::new(px2, py0, px3, py1),
+            RepeatMode::Stretch,
+            RepeatMode::Stretch,
+            BrushFlags::empty(),
+        );
+        // Bottom right
+        add_segment(
+            &mut segments,
+            LayoutRect::from_floats(br_inner.x, br_inner.y, br_outer.x, br_outer.y),
+            TexelRect::new(px2, py2, px3, py3),
+            RepeatMode::Stretch,
+            RepeatMode::Stretch,
+            BrushFlags::empty(),
+        );
+        // Bottom left
+        add_segment(
+            &mut segments,
+            LayoutRect::from_floats(bl_outer.x, bl_inner.y, bl_inner.x, bl_outer.y),
+            TexelRect::new(px0, py2, px1, py3),
+            RepeatMode::Stretch,
+            RepeatMode::Stretch,
+            BrushFlags::empty(),
+        );
+
+        // Center
+        if self.fill {
+            add_segment(
+                &mut segments,
+                LayoutRect::from_floats(tl_inner.x, tl_inner.y, tr_inner.x, bl_inner.y),
+                TexelRect::new(px1, py1, px2, py2),
+                self.repeat_horizontal,
+                self.repeat_vertical,
+                BrushFlags::SEGMENT_NINEPATCH_MIDDLE,
+            );
+        }
+
+        // Add edge segments.
+
+        // Top
+        add_segment(
+            &mut segments,
+            LayoutRect::from_floats(tl_inner.x, tl_outer.y, tr_inner.x, tl_inner.y),
+            TexelRect::new(px1, py0, px2, py1),
+            self.repeat_horizontal,
+            RepeatMode::Stretch,
+            BrushFlags::empty(),
+        );
+        // Bottom
+        add_segment(
+            &mut segments,
+            LayoutRect::from_floats(bl_inner.x, bl_inner.y, br_inner.x, bl_outer.y),
+            TexelRect::new(px1, py2, px2, py3),
+            self.repeat_horizontal,
+            RepeatMode::Stretch,
+            BrushFlags::empty(),
+        );
+        // Left
+        add_segment(
+            &mut segments,
+            LayoutRect::from_floats(tl_outer.x, tl_inner.y, tl_inner.x, bl_inner.y),
+            TexelRect::new(px0, py1, px1, py2),
+            RepeatMode::Stretch,
+            self.repeat_vertical,
+            BrushFlags::empty(),
+        );
+        // Right
+        add_segment(
+            &mut segments,
+            LayoutRect::from_floats(tr_inner.x, tr_inner.y, br_outer.x, br_inner.y),
+            TexelRect::new(px2, py1, px3, py2),
+            RepeatMode::Stretch,
+            self.repeat_vertical,
+            BrushFlags::empty(),
+        );
+
+        segments
+    }
+}