Initial implementation of WebGPU API

components/constellation/Cargo.toml

@@ -47,6 +47,7 @@ servo_geometry = {path = "../geometry"}
 servo_rand = {path = "../rand"}
 servo_remutex = {path = "../remutex"}
 servo_url = {path = "../url"}
+webgpu = {path = "../webgpu"}
 webvr_traits = {path = "../webvr_traits"}
 webrender_api = {git = "https://github.com/servo/webrender", features = ["ipc"]}
 webxr-api = {git = "https://github.com/servo/webxr", features = ["ipc"]}

components/constellation/constellation.rs

@@ -172,6 +172,7 @@ use std::sync::Arc;
 use std::thread;
 use style_traits::viewport::ViewportConstraints;
 use style_traits::CSSPixel;
+use webgpu::WebGPU;
 use webvr_traits::{WebVREvent, WebVRMsg};
 
 type PendingApprovalNavigations = HashMap<PipelineId, (LoadData, HistoryEntryReplacement)>;
@@ -440,6 +441,10 @@ pub struct Constellation<Message, LTF, STF> {
     /// Entry point to create and get channels to a WebGLThread.
     webgl_threads: Option<WebGLThreads>,
 
+    /// An IPC channel for the constellation to send messages to the
+    /// WebGPU threads.
+    webgpu: Option<WebGPU>,
+
     /// A channel through which messages can be sent to the webvr thread.
     webvr_chan: Option<IpcSender<WebVRMsg>>,
 
@@ -521,6 +526,9 @@ pub struct InitialConstellationState {
     /// Entry point to create and get channels to a WebGLThread.
     pub webgl_threads: Option<WebGLThreads>,
 
+    /// A channel to the WebGPU threads.
+    pub webgpu: Option<WebGPU>,
+
     /// A channel to the webgl thread.
     pub webvr_chan: Option<IpcSender<WebVRMsg>>,
 
@@ -836,6 +844,7 @@ where
                         (rng, prob)
                     }),
                     webgl_threads: state.webgl_threads,
+                    webgpu: state.webgpu,
                     webvr_chan: state.webvr_chan,
                     webxr_registry: state.webxr_registry,
                     canvas_chan: CanvasPaintThread::start(),
@@ -1090,6 +1099,7 @@ where
                 .webgl_threads
                 .as_ref()
                 .map(|threads| threads.pipeline()),
+            webgpu: self.webgpu.clone(),
             webvr_chan: self.webvr_chan.clone(),
             webxr_registry: self.webxr_registry.clone(),
             player_context: self.player_context.clone(),
@@ -2355,6 +2365,17 @@ where
             }
         }
 
+        if let Some(webgpu) = self.webgpu.as_ref() {
+            debug!("Exiting WebGPU thread.");
+            let (sender, receiver) = ipc::channel().expect("Failed to create IPC channel!");
+            if let Err(e) = webgpu.exit(sender) {
+                warn!("Exit WebGPU Thread failed ({})", e);
+            }
+            if let Err(e) = receiver.recv() {
+                warn!("Failed to receive exit response from WebGPU ({})", e);
+            }
+        }
+
         if let Some(chan) = self.webvr_chan.as_ref() {
             debug!("Exiting WebVR thread.");
             if let Err(e) = chan.send(WebVRMsg::Exit) {

components/constellation/pipeline.rs

@@ -46,6 +46,7 @@ use std::process;
 use std::rc::Rc;
 use std::sync::atomic::AtomicBool;
 use std::sync::Arc;
+use webgpu::WebGPU;
 use webvr_traits::WebVRMsg;
 
 /// A `Pipeline` is the constellation's view of a `Document`. Each pipeline has an
@@ -188,6 +189,9 @@ pub struct InitialPipelineState {
     /// A channel to the WebGL thread.
     pub webgl_chan: Option<WebGLPipeline>,
 
+    /// A channel to the WebGPU threads.
+    pub webgpu: Option<WebGPU>,
+
     /// A channel to the webvr thread.
     pub webvr_chan: Option<IpcSender<WebVRMsg>>,
 
@@ -299,6 +303,7 @@ impl Pipeline {
                     webrender_document: state.webrender_document,
                     webgl_chan: state.webgl_chan,
                     webvr_chan: state.webvr_chan,
+                    webgpu: state.webgpu,
                     webxr_registry: state.webxr_registry,
                     player_context: state.player_context,
                 };
@@ -504,6 +509,7 @@ pub struct UnprivilegedPipelineContent {
     webrender_api_sender: webrender_api::RenderApiSender,
     webrender_document: webrender_api::DocumentId,
     webgl_chan: Option<WebGLPipeline>,
+    webgpu: Option<WebGPU>,
     webvr_chan: Option<IpcSender<WebVRMsg>>,
     webxr_registry: webxr_api::Registry,
     player_context: WindowGLContext,
@@ -556,6 +562,7 @@ impl UnprivilegedPipelineContent {
                 pipeline_namespace_id: self.pipeline_namespace_id,
                 content_process_shutdown_chan: content_process_shutdown_chan,
                 webgl_chan: self.webgl_chan,
+                webgpu: self.webgpu,
                 webvr_chan: self.webvr_chan,
                 webxr_registry: self.webxr_registry,
                 webrender_document: self.webrender_document,