Auto merge of #9589 - glennw:webrender, r=pcwalton

Add WebRender integration to Servo.

WebRender is an experimental GPU accelerated rendering backend for Servo.

The WebRender backend can be specified by running Servo with the -w option (otherwise the default rendering backend will be used).

WebRender has many bugs, and missing features - but it is usable to browse most websites - please report any WebRender specific rendering bugs you encounter!

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3 files changed, 128 insertions, 15 deletions

diff --git a/components/servo/Cargo.lock b/components/servo/Cargo.lock
index 39b651e0912..9c4a7af6185 100644
--- a/components/servo/Cargo.lock
+++ b/components/servo/Cargo.lock
@@ -15,7 +15,7 @@ dependencies = [
  "gaol 0.0.1 (git+https://github.com/servo/gaol)",
  "gfx 0.0.1",
  "gfx_tests 0.0.1",
- "gleam 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "gleam 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "glutin_app 0.0.1",
  "image 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
@@ -42,6 +42,8 @@ dependencies = [
  "util 0.0.1",
  "util_tests 0.0.1",
  "webdriver_server 0.0.1",
+ "webrender 0.1.0 (git+https://github.com/glennw/webrender)",
+ "webrender_traits 0.1.0 (git+https://github.com/glennw/webrender_traits)",
 ]
 
 [[package]]
@@ -152,7 +154,7 @@ dependencies = [
  "canvas_traits 0.0.1",
  "euclid 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "gfx_traits 0.0.1",
- "gleam 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "gleam 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "layers 0.2.2 (git+https://github.com/servo/rust-layers)",
  "log 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -160,6 +162,7 @@ dependencies = [
  "offscreen_gl_context 0.1.0 (git+https://github.com/ecoal95/rust-offscreen-rendering-context)",
  "plugins 0.0.1",
  "util 0.0.1",
+ "webrender_traits 0.1.0 (git+https://github.com/glennw/webrender_traits)",
 ]
 
 [[package]]
@@ -179,6 +182,7 @@ dependencies = [
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "util 0.0.1",
+ "webrender_traits 0.1.0 (git+https://github.com/glennw/webrender_traits)",
 ]
 
 [[package]]
@@ -200,7 +204,7 @@ name = "cgl"
 version = "0.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "gleam 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "gleam 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -273,7 +277,7 @@ dependencies = [
  "gaol 0.0.1 (git+https://github.com/servo/gaol)",
  "gfx 0.0.1",
  "gfx_traits 0.0.1",
- "gleam 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "gleam 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "image 0.5.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
  "layers 0.2.2 (git+https://github.com/servo/rust-layers)",
@@ -292,6 +296,8 @@ dependencies = [
  "time 0.1.34 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 0.5.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "util 0.0.1",
+ "webrender 0.1.0 (git+https://github.com/glennw/webrender)",
+ "webrender_traits 0.1.0 (git+https://github.com/glennw/webrender_traits)",
 ]
 
 [[package]]
@@ -680,6 +686,7 @@ dependencies = [
  "unicode-script 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 0.5.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "util 0.0.1",
+ "webrender_traits 0.1.0 (git+https://github.com/glennw/webrender_traits)",
 ]
 
 [[package]]
@@ -728,7 +735,7 @@ dependencies = [
 
 [[package]]
 name = "gleam"
-version = "0.2.3"
+version = "0.2.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "gl_generator 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -748,7 +755,7 @@ dependencies = [
  "cgl 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "compositing 0.0.1",
  "euclid 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "gleam 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "gleam 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "layers 0.2.2 (git+https://github.com/servo/rust-layers)",
  "msg 0.0.1",
  "net_traits 0.0.1",
@@ -904,7 +911,7 @@ dependencies = [
  "cgl 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "core-foundation 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "gleam 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "gleam 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "leaky-cow 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -965,7 +972,7 @@ dependencies = [
  "cgl 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "core-foundation 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "gleam 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "gleam 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "glx 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "heapsize 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "heapsize_plugin 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1018,6 +1025,7 @@ dependencies = [
  "unicode-script 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 0.5.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "util 0.0.1",
+ "webrender_traits 0.1.0 (git+https://github.com/glennw/webrender_traits)",
 ]
 
 [[package]]
@@ -1034,6 +1042,7 @@ dependencies = [
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 0.5.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "util 0.0.1",
+ "webrender_traits 0.1.0 (git+https://github.com/glennw/webrender_traits)",
 ]
 
 [[package]]
@@ -1194,6 +1203,7 @@ dependencies = [
  "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 0.5.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "util 0.0.1",
+ "webrender_traits 0.1.0 (git+https://github.com/glennw/webrender_traits)",
 ]
 
 [[package]]
@@ -1218,6 +1228,7 @@ dependencies = [
  "url 0.5.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "util 0.0.1",
  "uuid 0.1.18 (registry+https://github.com/rust-lang/crates.io-index)",
+ "webrender_traits 0.1.0 (git+https://github.com/glennw/webrender_traits)",
  "websocket 0.14.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -1334,7 +1345,7 @@ dependencies = [
  "core-foundation 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "gl_generator 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "gleam 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "gleam 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "khronos_api 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1560,6 +1571,22 @@ version = "0.3.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "rustc_version"
+version = "0.1.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "semver 0.1.20 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "scoped_threadpool"
+version = "0.1.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rustc_version 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "script"
 version = "0.0.1"
 dependencies = [
@@ -1660,6 +1687,11 @@ dependencies = [
 ]
 
 [[package]]
+name = "semver"
+version = "0.1.20"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
 name = "serde"
 version = "0.6.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1766,7 +1798,7 @@ dependencies = [
  "cgl 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "expat-sys 2.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "gleam 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "gleam 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "glx 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "io-surface 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2175,6 +2207,42 @@ dependencies = [
 ]
 
 [[package]]
+name = "webrender"
+version = "0.1.0"
+source = "git+https://github.com/glennw/webrender#90cd6afdd64cdb48f606dbe0ce5d1ac352329004"
+dependencies = [
+ "app_units 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "core-graphics 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "core-text 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "fnv 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "freetype 0.1.0 (git+https://github.com/servo/rust-freetype)",
+ "gleam 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
+ "lazy_static 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "num 0.1.28 (registry+https://github.com/rust-lang/crates.io-index)",
+ "offscreen_gl_context 0.1.0 (git+https://github.com/ecoal95/rust-offscreen-rendering-context)",
+ "scoped_threadpool 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "time 0.1.34 (registry+https://github.com/rust-lang/crates.io-index)",
+ "webrender_traits 0.1.0 (git+https://github.com/glennw/webrender_traits)",
+]
+
+[[package]]
+name = "webrender_traits"
+version = "0.1.0"
+source = "git+https://github.com/glennw/webrender_traits#8ccc1608590d219d1df54e49f2f1e887995b4d60"
+dependencies = [
+ "app_units 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "core-graphics 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "euclid 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "gleam 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ipc-channel 0.2.0 (git+https://github.com/servo/ipc-channel)",
+ "offscreen_gl_context 0.1.0 (git+https://github.com/ecoal95/rust-offscreen-rendering-context)",
+ "serde 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_macros 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "websocket"
 version = "0.14.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
diff --git a/components/servo/Cargo.toml b/components/servo/Cargo.toml
index c4d2c6d9f36..9bea00cd956 100644
--- a/components/servo/Cargo.toml
+++ b/components/servo/Cargo.toml
@@ -52,6 +52,12 @@ name = "reftest"
 path = "../../tests/reftest.rs"
 harness = false
 
+[dependencies.webrender_traits]
+git = "https://github.com/glennw/webrender_traits"
+
+[dependencies.webrender]
+git = "https://github.com/glennw/webrender"
+
 [features]
 default = ["glutin_app", "window", "webdriver"]
 window = ["glutin_app/window"]
diff --git a/components/servo/lib.rs b/components/servo/lib.rs
index 6544b69e002..67b6875da48 100644
--- a/components/servo/lib.rs
+++ b/components/servo/lib.rs
@@ -48,6 +48,9 @@ mod export {
 #[cfg(feature = "webdriver")]
 extern crate webdriver_server;
 
+extern crate webrender;
+extern crate webrender_traits;
+
 #[cfg(feature = "webdriver")]
 fn webdriver(port: u16, constellation: Sender<ConstellationMsg>) {
     webdriver_server::start_server(port, constellation);
@@ -82,6 +85,7 @@ use std::borrow::Borrow;
 use std::rc::Rc;
 use std::sync::mpsc::Sender;
 use util::opts;
+use util::resource_files::resources_dir_path;
 
 pub use _util as util;
 pub use export::canvas;
@@ -147,6 +151,35 @@ impl Browser {
             devtools::start_server(port)
         });
 
+        let (webrender, webrender_api_sender) = if opts::get().use_webrender {
+            let mut resource_path = resources_dir_path();
+            resource_path.push("shaders");
+
+            // TODO(gw): Duplicates device_pixels_per_screen_px from compositor. Tidy up!
+            let hidpi_factor = window.as_ref()
+                                     .map(|window| window.hidpi_factor().get())
+                                     .unwrap_or(1.0);
+            let device_pixel_ratio = match opts.device_pixels_per_px {
+                Some(device_pixels_per_px) => device_pixels_per_px,
+                None => match opts.output_file {
+                    Some(_) => 1.0,
+                    None => hidpi_factor,
+                }
+            };
+
+            let (webrender, webrender_sender) =
+                webrender::Renderer::new(webrender::RendererOptions {
+                    device_pixel_ratio: device_pixel_ratio,
+                    resource_path: resource_path,
+                    enable_aa: opts.enable_text_antialiasing,
+                    enable_msaa: opts.use_msaa,
+                    enable_profiler: opts.webrender_stats,
+                });
+            (Some(webrender), Some(webrender_sender))
+        } else {
+            (None, None)
+        };
+
         // Create the constellation, which maintains the engine
         // pipelines, including the script and layout threads, as well
         // as the navigation context.
@@ -155,7 +188,8 @@ impl Browser {
                                                       time_profiler_chan.clone(),
                                                       mem_profiler_chan.clone(),
                                                       devtools_chan,
-                                                      supports_clipboard);
+                                                      supports_clipboard,
+                                                      webrender_api_sender.clone());
 
         if cfg!(feature = "webdriver") {
             if let Some(port) = opts.webdriver_port {
@@ -171,6 +205,8 @@ impl Browser {
             constellation_chan: constellation_chan,
             time_profiler_chan: time_profiler_chan,
             mem_profiler_chan: mem_profiler_chan,
+            webrender: webrender,
+            webrender_api_sender: webrender_api_sender,
         });
 
         Browser {
@@ -200,11 +236,13 @@ fn create_constellation(opts: opts::Opts,
                         time_profiler_chan: time::ProfilerChan,
                         mem_profiler_chan: mem::ProfilerChan,
                         devtools_chan: Option<Sender<devtools_traits::DevtoolsControlMsg>>,
-                        supports_clipboard: bool) -> Sender<ConstellationMsg> {
+                        supports_clipboard: bool,
+                        webrender_api_sender: Option<webrender_traits::RenderApiSender>) -> Sender<ConstellationMsg> {
     let resource_thread = new_resource_thread(opts.user_agent.clone(), devtools_chan.clone());
-
-    let image_cache_thread = new_image_cache_thread(resource_thread.clone());
-    let font_cache_thread = FontCacheThread::new(resource_thread.clone());
+    let image_cache_thread = new_image_cache_thread(resource_thread.clone(),
+                                                    webrender_api_sender.as_ref().map(|wr| wr.create_api()));
+    let font_cache_thread = FontCacheThread::new(resource_thread.clone(),
+                                                 webrender_api_sender.as_ref().map(|wr| wr.create_api()));
     let storage_thread: StorageThread = StorageThreadFactory::new();
 
     let initial_state = InitialConstellationState {
@@ -217,6 +255,7 @@ fn create_constellation(opts: opts::Opts,
         time_profiler_chan: time_profiler_chan,
         mem_profiler_chan: mem_profiler_chan,
         supports_clipboard: supports_clipboard,
+        webrender_api_sender: webrender_api_sender,
     };
     let constellation_chan =
         Constellation::<layout::layout_thread::LayoutThread,