Implement DOM to texture

This commit is contained in:
Imanol Fernandez 2017-09-21 15:16:46 +02:00
parent a9022be0c3
commit 8ae0739bab
17 changed files with 238 additions and 13 deletions

View file

@ -6,9 +6,12 @@ use ::gl_context::GLContextFactory;
use ::webgl_thread::{WebGLExternalImageApi, WebGLExternalImageHandler, WebGLThreadObserver, WebGLThread};
use canvas_traits::webgl::{WebGLChan, WebGLContextId, WebGLMsg, WebGLPipeline, WebGLReceiver};
use canvas_traits::webgl::{WebGLSender, WebVRCommand, WebVRRenderHandler};
use canvas_traits::webgl::DOMToTextureCommand;
use canvas_traits::webgl::webgl_channel;
use euclid::Size2D;
use fnv::FnvHashMap;
use gleam::gl;
use servo_config::prefs::PREFS;
use std::marker::PhantomData;
use std::rc::Rc;
use webrender;
@ -23,14 +26,19 @@ impl WebGLThreads {
webrender_gl: Rc<gl::Gl>,
webrender_api_sender: webrender_api::RenderApiSender,
webvr_compositor: Option<Box<WebVRRenderHandler>>)
-> (WebGLThreads, Box<webrender::ExternalImageHandler>) {
-> (WebGLThreads, Box<webrender::ExternalImageHandler>, Option<Box<webrender::OutputImageHandler>>) {
// This implementation creates a single `WebGLThread` for all the pipelines.
let channel = WebGLThread::start(gl_factory,
webrender_api_sender,
webvr_compositor.map(|c| WebVRRenderWrapper(c)),
PhantomData);
let output_handler = if PREFS.is_dom_to_texture_enabled() {
Some(Box::new(OutputHandler::new(webrender_gl.clone(), channel.clone())))
} else {
None
};
let external = WebGLExternalImageHandler::new(WebGLExternalImages::new(webrender_gl, channel.clone()));
(WebGLThreads(channel), Box::new(external))
(WebGLThreads(channel), Box::new(external), output_handler.map(|b| b as Box<_>))
}
/// Gets the WebGLThread handle for each script pipeline.
@ -105,3 +113,47 @@ impl WebVRRenderHandler for WebVRRenderWrapper {
self.0.handle(command, texture);
}
}
/// struct used to implement DOMToTexture feature and webrender::OutputImageHandler trait.
type OutputHandlerData = Option<(u32, Size2D<i32>)>;
struct OutputHandler {
webrender_gl: Rc<gl::Gl>,
webgl_channel: WebGLSender<WebGLMsg>,
// Used to avoid creating a new channel on each received WebRender request.
lock_channel: (WebGLSender<OutputHandlerData>, WebGLReceiver<OutputHandlerData>),
sync_objects: FnvHashMap<webrender_api::PipelineId, gl::GLsync>,
}
impl OutputHandler {
fn new(webrender_gl: Rc<gl::Gl>, channel: WebGLSender<WebGLMsg>) -> Self {
Self {
webrender_gl,
webgl_channel: channel,
lock_channel: webgl_channel().unwrap(),
sync_objects: Default::default(),
}
}
}
/// Bridge between the WR frame outputs and WebGL to implement DOMToTexture synchronization.
impl webrender::OutputImageHandler for OutputHandler {
fn lock(&mut self, id: webrender_api::PipelineId) -> Option<(u32, webrender_api::DeviceIntSize)> {
// Insert a fence in the WR command queue
let gl_sync = self.webrender_gl.fence_sync(gl::SYNC_GPU_COMMANDS_COMPLETE, 0);
// The lock command adds a WaitSync call on the WebGL command flow.
let command = DOMToTextureCommand::Lock(id, gl_sync as usize, self.lock_channel.0.clone());
self.webgl_channel.send(WebGLMsg::DOMToTextureCommand(command)).unwrap();
self.lock_channel.1.recv().unwrap().map(|(tex_id, size)| {
(tex_id, webrender_api::DeviceIntSize::new(size.width, size.height))
})
}
fn unlock(&mut self, id: webrender_api::PipelineId) {
if let Some(gl_sync) = self.sync_objects.remove(&id) {
// Flush the Sync object into the GPU's command queue to guarantee that it it's signaled.
self.webrender_gl.flush();
// Mark the sync object for deletion.
self.webrender_gl.delete_sync(gl_sync);
}
}
}