Auto merge of #17891 - MortimerGoro:webgl_move, r=glennw,emilio

Improved WebGL architecture

<!-- Please describe your changes on the following line: -->

Info about the big picture and the goals of the WebGL refactor in this thread: https://groups.google.com/forum/#!topic/mozilla.dev.servo/0WMGz60kKzQ

I tried to reduce this PR as much as possible as requested in the thread. I'll do separate PRs for other features (e.g.: Batch messages or use shared memory to improve frame times) or fixes.

Some tips to ease the review process:
- Most changes in DOM objects follow the same pattern (remove CanvasMsg wrapper and use the new sender method).
- WebGLCommands are the same ones as before (moved from webrender_api). So those lines are already reviewed.
- See WebGL traits in [components/canvas_traits/webgl.rs](https://github.com/servo/servo/pull/17891/files#diff-8701045d01505418701d0631d4d45562)
- See WebGLThread and WR External Image bridge in [components/canvas/webgl_thread.rs](https://github.com/servo/servo/pull/17891/files#diff-281554879f39a2a041f7a69d442a5d2e)
- The implementation submitted in this PR creates a single `WebGLThread` for all ScriptThread/Pipelines. See that in [components/canvas/webgl_mode/inprocess.rs](https://github.com/servo/servo/pull/17891/files#diff-250070c6c5a38c7f9fa0f5b3c101f68b)

The conformance tests will help to guarantee that we don't miss anything.

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

<!-- Either: -->
- [x] There are tests for these changes OR
- [ ] These changes do not require tests because _____

<!-- Also, please make sure that "Allow edits from maintainers" checkbox is checked, so that we can help you if you get stuck somewhere along the way.-->

<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->

<!-- Reviewable:start -->
---
This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/servo/17891)
<!-- Reviewable:end -->

1 files changed, 27 insertions, 29 deletions

diff --git a/components/script/dom/webglprogram.rs b/components/script/dom/webglprogram.rs
index c76a2f3da18..6c298bb83fb 100644
--- a/components/script/dom/webglprogram.rs
+++ b/components/script/dom/webglprogram.rs
@@ -3,7 +3,8 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 // https://www.khronos.org/registry/webgl/specs/latest/1.0/webgl.idl
-use canvas_traits::CanvasMsg;
+use canvas_traits::webgl::{WebGLCommand, WebGLError, WebGLMsgSender, WebGLParameter, WebGLProgramId, WebGLResult};
+use canvas_traits::webgl::webgl_channel;
 use dom::bindings::codegen::Bindings::WebGLProgramBinding;
 use dom::bindings::codegen::Bindings::WebGLRenderingContextBinding::WebGLRenderingContextConstants as constants;
 use dom::bindings::js::{MutNullableJS, Root};
@@ -15,10 +16,7 @@ use dom::webglrenderingcontext::MAX_UNIFORM_AND_ATTRIBUTE_LEN;
 use dom::webglshader::WebGLShader;
 use dom::window::Window;
 use dom_struct::dom_struct;
-use ipc_channel::ipc::IpcSender;
 use std::cell::Cell;
-use webrender_api;
-use webrender_api::{WebGLCommand, WebGLError, WebGLParameter, WebGLProgramId, WebGLResult};
 
 #[dom_struct]
 pub struct WebGLProgram {
@@ -30,11 +28,11 @@ pub struct WebGLProgram {
     fragment_shader: MutNullableJS<WebGLShader>,
     vertex_shader: MutNullableJS<WebGLShader>,
     #[ignore_heap_size_of = "Defined in ipc-channel"]
-    renderer: IpcSender<CanvasMsg>,
+    renderer: WebGLMsgSender,
 }
 
 impl WebGLProgram {
-    fn new_inherited(renderer: IpcSender<CanvasMsg>,
+    fn new_inherited(renderer: WebGLMsgSender,
                      id: WebGLProgramId)
                      -> WebGLProgram {
         WebGLProgram {
@@ -49,17 +47,17 @@ impl WebGLProgram {
         }
     }
 
-    pub fn maybe_new(window: &Window, renderer: IpcSender<CanvasMsg>)
+    pub fn maybe_new(window: &Window, renderer: WebGLMsgSender)
                      -> Option<Root<WebGLProgram>> {
-        let (sender, receiver) = webrender_api::channel::msg_channel().unwrap();
-        renderer.send(CanvasMsg::WebGL(WebGLCommand::CreateProgram(sender))).unwrap();
+        let (sender, receiver) = webgl_channel().unwrap();
+        renderer.send(WebGLCommand::CreateProgram(sender)).unwrap();
 
         let result = receiver.recv().unwrap();
         result.map(|program_id| WebGLProgram::new(window, renderer, program_id))
     }
 
     pub fn new(window: &Window,
-               renderer: IpcSender<CanvasMsg>,
+               renderer: WebGLMsgSender,
                id: WebGLProgramId)
                -> Root<WebGLProgram> {
         reflect_dom_object(box WebGLProgram::new_inherited(renderer, id),
@@ -78,7 +76,7 @@ impl WebGLProgram {
     pub fn delete(&self) {
         if !self.is_deleted.get() {
             self.is_deleted.set(true);
-            let _ = self.renderer.send(CanvasMsg::WebGL(WebGLCommand::DeleteProgram(self.id)));
+            let _ = self.renderer.send(WebGLCommand::DeleteProgram(self.id));
 
             if let Some(shader) = self.fragment_shader.get() {
                 shader.decrement_attached_counter();
@@ -117,7 +115,7 @@ impl WebGLProgram {
         }
 
         self.linked.set(true);
-        self.renderer.send(CanvasMsg::WebGL(WebGLCommand::LinkProgram(self.id))).unwrap();
+        self.renderer.send(WebGLCommand::LinkProgram(self.id)).unwrap();
         Ok(())
     }
 
@@ -130,7 +128,7 @@ impl WebGLProgram {
             return Err(WebGLError::InvalidOperation);
         }
 
-        self.renderer.send(CanvasMsg::WebGL(WebGLCommand::UseProgram(self.id))).unwrap();
+        self.renderer.send(WebGLCommand::UseProgram(self.id)).unwrap();
         Ok(())
     }
 
@@ -139,7 +137,7 @@ impl WebGLProgram {
         if self.is_deleted() {
             return Err(WebGLError::InvalidOperation);
         }
-        self.renderer.send(CanvasMsg::WebGL(WebGLCommand::ValidateProgram(self.id))).unwrap();
+        self.renderer.send(WebGLCommand::ValidateProgram(self.id)).unwrap();
         Ok(())
     }
 
@@ -166,7 +164,7 @@ impl WebGLProgram {
         shader_slot.set(Some(shader));
         shader.increment_attached_counter();
 
-        self.renderer.send(CanvasMsg::WebGL(WebGLCommand::AttachShader(self.id, shader.id()))).unwrap();
+        self.renderer.send(WebGLCommand::AttachShader(self.id, shader.id())).unwrap();
 
         Ok(())
     }
@@ -196,7 +194,7 @@ impl WebGLProgram {
         shader_slot.set(None);
         shader.decrement_attached_counter();
 
-        self.renderer.send(CanvasMsg::WebGL(WebGLCommand::DetachShader(self.id, shader.id()))).unwrap();
+        self.renderer.send(WebGLCommand::DetachShader(self.id, shader.id())).unwrap();
 
         Ok(())
     }
@@ -216,7 +214,7 @@ impl WebGLProgram {
         }
 
         self.renderer
-            .send(CanvasMsg::WebGL(WebGLCommand::BindAttribLocation(self.id, index, String::from(name))))
+            .send(WebGLCommand::BindAttribLocation(self.id, index, String::from(name)))
             .unwrap();
         Ok(())
     }
@@ -225,9 +223,9 @@ impl WebGLProgram {
         if self.is_deleted() {
             return Err(WebGLError::InvalidValue);
         }
-        let (sender, receiver) = webrender_api::channel::msg_channel().unwrap();
+        let (sender, receiver) = webgl_channel().unwrap();
         self.renderer
-            .send(CanvasMsg::WebGL(WebGLCommand::GetActiveUniform(self.id, index, sender)))
+            .send(WebGLCommand::GetActiveUniform(self.id, index, sender))
             .unwrap();
 
         receiver.recv().unwrap().map(|(size, ty, name)|
@@ -239,9 +237,9 @@ impl WebGLProgram {
         if self.is_deleted() {
             return Err(WebGLError::InvalidValue);
         }
-        let (sender, receiver) = webrender_api::channel::msg_channel().unwrap();
+        let (sender, receiver) = webgl_channel().unwrap();
         self.renderer
-            .send(CanvasMsg::WebGL(WebGLCommand::GetActiveAttrib(self.id, index, sender)))
+            .send(WebGLCommand::GetActiveAttrib(self.id, index, sender))
             .unwrap();
 
         receiver.recv().unwrap().map(|(size, ty, name)|
@@ -266,9 +264,9 @@ impl WebGLProgram {
             return Ok(None);
         }
 
-        let (sender, receiver) = webrender_api::channel::msg_channel().unwrap();
+        let (sender, receiver) = webgl_channel().unwrap();
         self.renderer
-            .send(CanvasMsg::WebGL(WebGLCommand::GetAttribLocation(self.id, String::from(name), sender)))
+            .send(WebGLCommand::GetAttribLocation(self.id, String::from(name), sender))
             .unwrap();
         Ok(receiver.recv().unwrap())
     }
@@ -287,9 +285,9 @@ impl WebGLProgram {
             return Ok(None);
         }
 
-        let (sender, receiver) = webrender_api::channel::msg_channel().unwrap();
+        let (sender, receiver) = webgl_channel().unwrap();
         self.renderer
-            .send(CanvasMsg::WebGL(WebGLCommand::GetUniformLocation(self.id, String::from(name), sender)))
+            .send(WebGLCommand::GetUniformLocation(self.id, String::from(name), sender))
             .unwrap();
         Ok(receiver.recv().unwrap())
     }
@@ -308,15 +306,15 @@ impl WebGLProgram {
                 return Ok("One or more shaders failed to compile".to_string());
             }
         }
-        let (sender, receiver) = webrender_api::channel::msg_channel().unwrap();
-        self.renderer.send(CanvasMsg::WebGL(WebGLCommand::GetProgramInfoLog(self.id, sender))).unwrap();
+        let (sender, receiver) = webgl_channel().unwrap();
+        self.renderer.send(WebGLCommand::GetProgramInfoLog(self.id, sender)).unwrap();
         Ok(receiver.recv().unwrap())
     }
 
     /// glGetProgramParameter
     pub fn parameter(&self, param_id: u32) -> WebGLResult<WebGLParameter> {
-        let (sender, receiver) = webrender_api::channel::msg_channel().unwrap();
-        self.renderer.send(CanvasMsg::WebGL(WebGLCommand::GetProgramParameter(self.id, param_id, sender))).unwrap();
+        let (sender, receiver) = webgl_channel().unwrap();
+        self.renderer.send(WebGLCommand::GetProgramParameter(self.id, param_id, sender)).unwrap();
         receiver.recv().unwrap()
     }
 }