Adding upstream version 110.0.1.upstream/110.0.1upstream

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

1 files changed, 290 insertions, 0 deletions

diff --git a/gfx/wr/examples/blob.rs b/gfx/wr/examples/blob.rs
new file mode 100644
index 0000000000..206944c1fb
--- /dev/null
+++ b/gfx/wr/examples/blob.rs
@@ -0,0 +1,290 @@
+/* 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/. */
+
+extern crate gleam;
+extern crate glutin;
+extern crate rayon;
+extern crate webrender;
+extern crate winit;
+
+#[path = "common/boilerplate.rs"]
+mod boilerplate;
+
+use crate::boilerplate::{Example, HandyDandyRectBuilder};
+use rayon::{ThreadPool, ThreadPoolBuilder};
+use rayon::prelude::*;
+use std::collections::HashMap;
+use std::sync::Arc;
+use webrender::api::{self, DisplayListBuilder, DocumentId, PipelineId, PrimitiveFlags};
+use webrender::api::{ColorF, CommonItemProperties, SpaceAndClipInfo, ImageDescriptorFlags};
+use webrender::api::units::*;
+use webrender::render_api::*;
+use webrender::euclid::size2;
+
+// This example shows how to implement a very basic BlobImageHandler that can only render
+// a checkerboard pattern.
+
+// The deserialized command list internally used by this example is just a color.
+type ImageRenderingCommands = api::ColorU;
+
+// Serialize/deserialize the blob.
+// For real usecases you should probably use serde rather than doing it by hand.
+
+fn serialize_blob(color: api::ColorU) -> Arc<Vec<u8>> {
+    Arc::new(vec![color.r, color.g, color.b, color.a])
+}
+
+fn deserialize_blob(blob: &[u8]) -> Result<ImageRenderingCommands, ()> {
+    let mut iter = blob.iter();
+    return match (iter.next(), iter.next(), iter.next(), iter.next()) {
+        (Some(&r), Some(&g), Some(&b), Some(&a)) => Ok(api::ColorU::new(r, g, b, a)),
+        (Some(&a), None, None, None) => Ok(api::ColorU::new(a, a, a, a)),
+        _ => Err(()),
+    };
+}
+
+// This is the function that applies the deserialized drawing commands and generates
+// actual image data.
+fn render_blob(
+    commands: Arc<ImageRenderingCommands>,
+    descriptor: &api::BlobImageDescriptor,
+    tile: TileOffset,
+) -> api::BlobImageResult {
+    let color = *commands;
+
+    // Note: This implementation ignores the dirty rect which isn't incorrect
+    // but is a missed optimization.
+
+    // Allocate storage for the result. Right now the resource cache expects the
+    // tiles to have have no stride or offset.
+    let bpp = 4;
+    let mut texels = Vec::with_capacity((descriptor.rect.area() * bpp) as usize);
+
+    // Generate a per-tile pattern to see it in the demo. For a real use case it would not
+    // make sense for the rendered content to depend on its tile.
+    let tile_checker = (tile.x % 2 == 0) != (tile.y % 2 == 0);
+
+    let [w, h] = descriptor.rect.size().to_array();
+    let offset = descriptor.rect.min;
+
+    for y in 0..h {
+        for x in 0..w {
+            // Apply the tile's offset. This is important: all drawing commands should be
+            // translated by this offset to give correct results with tiled blob images.
+            let x2 = x + offset.x;
+            let y2 = y + offset.y;
+
+            // Render a simple checkerboard pattern
+            let checker = if (x2 % 20 >= 10) != (y2 % 20 >= 10) {
+                1
+            } else {
+                0
+            };
+            // ..nested in the per-tile checkerboard pattern
+            let tc = if tile_checker { 0 } else { (1 - checker) * 40 };
+
+            match descriptor.format {
+                api::ImageFormat::BGRA8 => {
+                    texels.push(color.b * checker + tc);
+                    texels.push(color.g * checker + tc);
+                    texels.push(color.r * checker + tc);
+                    texels.push(color.a * checker + tc);
+                }
+                api::ImageFormat::R8 => {
+                    texels.push(color.a * checker + tc);
+                }
+                _ => {
+                    return Err(api::BlobImageError::Other(
+                        format!("Unsupported image format"),
+                    ));
+                }
+            }
+        }
+    }
+
+    Ok(api::RasterizedBlobImage {
+        data: Arc::new(texels),
+        rasterized_rect: size2(w, h).into(),
+    })
+}
+
+struct CheckerboardRenderer {
+    // We are going to defer the rendering work to worker threads.
+    // Using a pre-built Arc<ThreadPool> rather than creating our own threads
+    // makes it possible to share the same thread pool as the glyph renderer (if we
+    // want to).
+    workers: Arc<ThreadPool>,
+
+    // The deserialized drawing commands.
+    // In this example we store them in Arcs. This isn't necessary since in this simplified
+    // case the command list is a simple 32 bits value and would be cheap to clone before sending
+    // to the workers. But in a more realistic scenario the commands would typically be bigger
+    // and more expensive to clone, so let's pretend it is also the case here.
+    image_cmds: HashMap<api::BlobImageKey, Arc<ImageRenderingCommands>>,
+}
+
+impl CheckerboardRenderer {
+    fn new(workers: Arc<ThreadPool>) -> Self {
+        CheckerboardRenderer {
+            image_cmds: HashMap::new(),
+            workers,
+        }
+    }
+}
+
+impl api::BlobImageHandler for CheckerboardRenderer {
+    fn create_similar(&self) -> Box<dyn api::BlobImageHandler> {
+        Box::new(CheckerboardRenderer::new(Arc::clone(&self.workers)))
+    }
+
+    fn add(&mut self, key: api::BlobImageKey, cmds: Arc<api::BlobImageData>,
+           _visible_rect: &DeviceIntRect, _: api::TileSize) {
+        self.image_cmds
+            .insert(key, Arc::new(deserialize_blob(&cmds[..]).unwrap()));
+    }
+
+    fn update(&mut self, key: api::BlobImageKey, cmds: Arc<api::BlobImageData>,
+              _visible_rect: &DeviceIntRect, _dirty_rect: &BlobDirtyRect) {
+        // Here, updating is just replacing the current version of the commands with
+        // the new one (no incremental updates).
+        self.image_cmds
+            .insert(key, Arc::new(deserialize_blob(&cmds[..]).unwrap()));
+    }
+
+    fn delete(&mut self, key: api::BlobImageKey) {
+        self.image_cmds.remove(&key);
+    }
+
+    fn prepare_resources(
+        &mut self,
+        _services: &dyn api::BlobImageResources,
+        _requests: &[api::BlobImageParams],
+    ) {}
+
+    fn enable_multithreading(&mut self, _: bool) {}
+    fn delete_font(&mut self, _font: api::FontKey) {}
+    fn delete_font_instance(&mut self, _instance: api::FontInstanceKey) {}
+    fn clear_namespace(&mut self, _namespace: api::IdNamespace) {}
+    fn create_blob_rasterizer(&mut self) -> Box<dyn api::AsyncBlobImageRasterizer> {
+        Box::new(Rasterizer {
+            workers: Arc::clone(&self.workers),
+            image_cmds: self.image_cmds.clone(),
+        })
+    }
+}
+
+struct Rasterizer {
+    workers: Arc<ThreadPool>,
+    image_cmds: HashMap<api::BlobImageKey, Arc<ImageRenderingCommands>>,
+}
+
+impl api::AsyncBlobImageRasterizer for Rasterizer {
+    fn rasterize(
+        &mut self,
+        requests: &[api::BlobImageParams],
+        _low_priority: bool
+    ) -> Vec<(api::BlobImageRequest, api::BlobImageResult)> {
+        let requests: Vec<(&api::BlobImageParams, Arc<ImageRenderingCommands>)> = requests.into_iter().map(|params| {
+            (params, Arc::clone(&self.image_cmds[&params.request.key]))
+        }).collect();
+
+        self.workers.install(|| {
+            requests.into_par_iter().map(|(params, commands)| {
+                (params.request, render_blob(commands, &params.descriptor, params.request.tile))
+            }).collect()
+        })
+    }
+}
+
+struct App {}
+
+impl Example for App {
+    fn render(
+        &mut self,
+        api: &mut RenderApi,
+        builder: &mut DisplayListBuilder,
+        txn: &mut Transaction,
+        _device_size: DeviceIntSize,
+        pipeline_id: PipelineId,
+        _document_id: DocumentId,
+    ) {
+        let space_and_clip = SpaceAndClipInfo::root_scroll(pipeline_id);
+
+        builder.push_simple_stacking_context(
+            LayoutPoint::zero(),
+            space_and_clip.spatial_id,
+            PrimitiveFlags::IS_BACKFACE_VISIBLE,
+        );
+
+        let size1 = DeviceIntSize::new(500, 500);
+        let blob_img1 = api.generate_blob_image_key();
+        txn.add_blob_image(
+            blob_img1,
+            api::ImageDescriptor::new(
+                size1.width,
+                size1.height,
+                api::ImageFormat::BGRA8,
+                ImageDescriptorFlags::IS_OPAQUE,
+            ),
+            serialize_blob(api::ColorU::new(50, 50, 150, 255)),
+            size1.into(),
+            Some(128),
+        );
+        let bounds = (30, 30).by(size1.width, size1.height);
+        builder.push_image(
+            &CommonItemProperties::new(bounds, space_and_clip),
+            bounds,
+            api::ImageRendering::Auto,
+            api::AlphaType::PremultipliedAlpha,
+            blob_img1.as_image(),
+            ColorF::WHITE,
+        );
+
+        let size2 = DeviceIntSize::new(256, 256);
+        let blob_img2 = api.generate_blob_image_key();
+        txn.add_blob_image(
+            blob_img2,
+            api::ImageDescriptor::new(
+                size2.width,
+                size2.height,
+                api::ImageFormat::BGRA8,
+                ImageDescriptorFlags::IS_OPAQUE,
+            ),
+            serialize_blob(api::ColorU::new(50, 150, 50, 255)),
+            size2.into(),
+            None,
+        );
+        let bounds = (600, 600).by(size2.width, size2.height);
+        builder.push_image(
+            &CommonItemProperties::new(bounds, space_and_clip),
+            bounds,
+            api::ImageRendering::Auto,
+            api::AlphaType::PremultipliedAlpha,
+            blob_img2.as_image(),
+            ColorF::WHITE,
+        );
+
+        builder.pop_stacking_context();
+    }
+}
+
+fn main() {
+    let workers =
+        ThreadPoolBuilder::new().thread_name(|idx| format!("WebRender:Worker#{}", idx))
+                                .build();
+
+    let workers = Arc::new(workers.unwrap());
+
+    let opts = webrender::WebRenderOptions {
+        workers: Some(Arc::clone(&workers)),
+        // Register our blob renderer, so that WebRender integrates it in the resource cache..
+        // Share the same pool of worker threads between WebRender and our blob renderer.
+        blob_image_handler: Some(Box::new(CheckerboardRenderer::new(Arc::clone(&workers)))),
+        ..Default::default()
+    };
+
+    let mut app = App {};
+
+    boilerplate::main_wrapper(&mut app, Some(opts));
+}