Improve Webrender<->WebGL synchronization

This commit is contained in:
Imanol Fernandez 2017-09-20 11:30:35 +02:00
parent 8000efac75
commit 324e56b3d1
4 changed files with 31 additions and 15 deletions

View file

@ -8,7 +8,9 @@ use canvas_traits::webgl::{WebGLChan, WebGLContextId, WebGLMsg, WebGLPipeline, W
use canvas_traits::webgl::{WebGLSender, WebVRCommand, WebVRRenderHandler};
use canvas_traits::webgl::webgl_channel;
use euclid::Size2D;
use gleam::gl;
use std::marker::PhantomData;
use std::rc::Rc;
use webrender;
use webrender_api;
@ -18,6 +20,7 @@ pub struct WebGLThreads(WebGLSender<WebGLMsg>);
impl WebGLThreads {
/// Creates a new WebGLThreads object
pub fn new(gl_factory: GLContextFactory,
webrender_gl: Rc<gl::Gl>,
webrender_api_sender: webrender_api::RenderApiSender,
webvr_compositor: Option<Box<WebVRRenderHandler>>)
-> (WebGLThreads, Box<webrender::ExternalImageHandler>) {
@ -26,7 +29,7 @@ impl WebGLThreads {
webrender_api_sender,
webvr_compositor.map(|c| WebVRRenderWrapper(c)),
PhantomData);
let external = WebGLExternalImageHandler::new(WebGLExternalImages::new(channel.clone()));
let external = WebGLExternalImageHandler::new(WebGLExternalImages::new(webrender_gl, channel.clone()));
(WebGLThreads(channel), Box::new(external))
}
@ -44,14 +47,16 @@ impl WebGLThreads {
/// Bridge between the webrender::ExternalImage callbacks and the WebGLThreads.
struct WebGLExternalImages {
webrender_gl: Rc<gl::Gl>,
webgl_channel: WebGLSender<WebGLMsg>,
// Used to avoid creating a new channel on each received WebRender request.
lock_channel: (WebGLSender<(u32, Size2D<i32>)>, WebGLReceiver<(u32, Size2D<i32>)>),
lock_channel: (WebGLSender<(u32, Size2D<i32>, usize)>, WebGLReceiver<(u32, Size2D<i32>, usize)>),
}
impl WebGLExternalImages {
fn new(channel: WebGLSender<WebGLMsg>) -> Self {
fn new(webrender_gl: Rc<gl::Gl>, channel: WebGLSender<WebGLMsg>) -> Self {
Self {
webrender_gl,
webgl_channel: channel,
lock_channel: webgl_channel().unwrap(),
}
@ -60,8 +65,15 @@ impl WebGLExternalImages {
impl WebGLExternalImageApi for WebGLExternalImages {
fn lock(&mut self, ctx_id: WebGLContextId) -> (u32, Size2D<i32>) {
// WebGL Thread has it's own GL command queue that we need to synchronize with the WR GL command queue.
// The WebGLMsg::Lock message inserts a fence in the WebGL command queue.
self.webgl_channel.send(WebGLMsg::Lock(ctx_id, self.lock_channel.0.clone())).unwrap();
self.lock_channel.1.recv().unwrap()
let (image_id, size, gl_sync) = self.lock_channel.1.recv().unwrap();
// The next glWaitSync call is run on the WR thread and it's used to synchronize the two
// flows of OpenGL commands in order to avoid WR using a semi-ready WebGL texture.
// glWaitSync doesn't block WR thread, it affects only internal OpenGL subsystem.
self.webrender_gl.wait_sync(gl_sync as gl::GLsync, 0, gl::TIMEOUT_IGNORED);
(image_id, size)
}
fn unlock(&mut self, ctx_id: WebGLContextId) {