[rs] Merge #569

569: Reorder framework canvas setup for web r=kvark a=grovesNL

winit only appends the canvas element once the window is built, and we need the canvas to exist before `create_surface` can use it. So we can just reorder the calls to build the window before using `create_surface` on the web backend in framework.

Also temporarily no-op debug markers for the web until we have them in gecko. Even though they're technically unimplemented, we can still proceed without them.

Co-authored-by: Joshua Groves <josh@joshgroves.com>

wgpu/examples/framework.rs

@@ -80,9 +80,6 @@ async fn setup<E: Example>(title: &str) -> Setup {
         );
     };
 
-    #[cfg(target_arch = "wasm32")]
-    console_log::init().expect("could not initialize logger");
-
     let event_loop = EventLoop::new();
     let mut builder = winit::window::WindowBuilder::new();
     builder = builder.with_title(title);
@@ -93,6 +90,22 @@ async fn setup<E: Example>(title: &str) -> Setup {
     }
     let window = builder.build(&event_loop).unwrap();
 
+    #[cfg(target_arch = "wasm32")]
+    {
+        use winit::platform::web::WindowExtWebSys;
+        console_log::init().expect("could not initialize logger");
+        std::panic::set_hook(Box::new(console_error_panic_hook::hook));
+        // On wasm, append the canvas to the document body
+        web_sys::window()
+            .and_then(|win| win.document())
+            .and_then(|doc| doc.body())
+            .and_then(|body| {
+                body.append_child(&web_sys::Element::from(window.canvas()))
+                    .ok()
+            })
+            .expect("couldn't append canvas to document body");
+    }
+
     log::info!("Initializing the surface...");
 
     let instance = wgpu::Instance::new(wgpu::BackendBit::PRIMARY);
@@ -101,7 +114,6 @@ async fn setup<E: Example>(title: &str) -> Setup {
         let surface = instance.create_surface(&window);
         (size, surface)
     };
-
     let adapter = instance
         .request_adapter(&wgpu::RequestAdapterOptions {
             power_preference: wgpu::PowerPreference::Default,
@@ -109,7 +121,6 @@ async fn setup<E: Example>(title: &str) -> Setup {
         })
         .await
         .unwrap();
-
     let optional_features = E::optional_features();
     let required_features = E::required_features();
     let adapter_features = adapter.features();
@@ -168,7 +179,6 @@ fn start<E: Example>(
     #[cfg(target_arch = "wasm32")]
     let spawner = {
         use futures::{future::LocalFutureObj, task::SpawnError};
-        use winit::platform::web::WindowExtWebSys;
 
         struct WebSpawner {}
         impl LocalSpawn for WebSpawner {
@@ -180,18 +190,6 @@ fn start<E: Example>(
             }
         }
 
-        std::panic::set_hook(Box::new(console_error_panic_hook::hook));
-
-        // On wasm, append the canvas to the document body
-        web_sys::window()
-            .and_then(|win| win.document())
-            .and_then(|doc| doc.body())
-            .and_then(|body| {
-                body.append_child(&web_sys::Element::from(window.canvas()))
-                    .ok()
-            })
-            .expect("couldn't append canvas to document body");
-
         WebSpawner {}
     };
 

wgpu/src/backend/web.rs

@@ -90,15 +90,15 @@ impl crate::ComputePassInner<Context> for ComputePass {
     }
 
     fn insert_debug_marker(&mut self, _label: &str) {
-        unimplemented!()
+        // TODO
     }
 
     fn push_debug_group(&mut self, _group_label: &str) {
-        unimplemented!()
+        // TODO
     }
 
     fn pop_debug_group(&mut self) {
-        unimplemented!()
+        // TODO
     }
 
     fn dispatch(&mut self, x: u32, y: u32, z: u32) {
@@ -263,15 +263,15 @@ impl crate::RenderPassInner<Context> for RenderPass {
     }
 
     fn insert_debug_marker(&mut self, _label: &str) {
-        unimplemented!()
+        // TODO
     }
 
     fn push_debug_group(&mut self, _group_label: &str) {
-        unimplemented!()
+        // TODO
     }
 
     fn pop_debug_group(&mut self) {
-        unimplemented!()
+        // TODO
     }
 
     fn execute_bundles<'a, I: Iterator<Item = &'a ()>>(&mut self, _render_bundles: I) {
@@ -1465,13 +1465,13 @@ impl crate::Context for Context {
     }
 
     fn command_encoder_insert_debug_marker(&self, encoder: &Self::CommandEncoderId, label: &str) {
-        unimplemented!()
+        // TODO
     }
     fn command_encoder_push_debug_group(&self, encoder: &Self::CommandEncoderId, label: &str) {
-        unimplemented!()
+        // TODO
     }
     fn command_encoder_pop_debug_group(&self, encoder: &Self::CommandEncoderId) {
-        unimplemented!()
+        // TODO
     }
 
     fn render_bundle_encoder_finish(