Fix minimal-web example build errors

- Closes #406

examples/minimal-web/src/main.rs

@@ -3,7 +3,7 @@
 
 use error_iter::ErrorIter as _;
 use log::error;
-use pixels::{Pixels, SurfaceTexture};
+use pixels::{PixelsBuilder, SurfaceTexture};
 use std::rc::Rc;
 use winit::dpi::LogicalSize;
 use winit::event::{Event, WindowEvent};
@@ -41,6 +41,16 @@ fn main() {
     }
 }
 
+#[cfg(target_arch = "wasm32")]
+/// Retrieve current width and height dimensions of browser client window
+fn get_window_size() -> LogicalSize<f64> {
+    let client_window = web_sys::window().unwrap();
+    LogicalSize::new(
+        client_window.inner_width().unwrap().as_f64().unwrap(),
+        client_window.inner_height().unwrap().as_f64().unwrap(),
+    )
+}
+
 async fn run() {
     let event_loop = EventLoop::new().unwrap();
     let window = {
@@ -60,90 +70,96 @@ async fn run() {
         use wasm_bindgen::JsCast;
         use winit::platform::web::WindowExtWebSys;
 
-        // Retrieve current width and height dimensions of browser client window
-        let get_window_size = || {
-            let client_window = web_sys::window().unwrap();
-            LogicalSize::new(
-                client_window.inner_width().unwrap().as_f64().unwrap(),
-                client_window.inner_height().unwrap().as_f64().unwrap(),
-            )
-        };
-
-        let window = Rc::clone(&window);
-
-        // Initialize winit window with current dimensions of browser client
-        window.set_inner_size(get_window_size());
-
-        let client_window = web_sys::window().unwrap();
-
         // Attach winit canvas to body element
         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()))
+                body.append_child(&web_sys::Element::from(window.canvas().unwrap()))
                     .ok()
             })
             .expect("couldn't append canvas to document body");
 
         // Listen for resize event on browser client. Adjust winit window dimensions
         // on event trigger
-        let closure = wasm_bindgen::closure::Closure::wrap(Box::new(move |_e: web_sys::Event| {
-            let size = get_window_size();
-            window.set_inner_size(size)
+        let closure = wasm_bindgen::closure::Closure::wrap(Box::new({
+            let window = Rc::clone(&window);
+            move |_e: web_sys::Event| {
+                let _ = window.request_inner_size(get_window_size());
+            }
         }) as Box<dyn FnMut(_)>);
-        client_window
+        web_sys::window()
+            .unwrap()
             .add_event_listener_with_callback("resize", closure.as_ref().unchecked_ref())
             .unwrap();
         closure.forget();
+
+        // Trigger initial resize event
+        let _ = window.request_inner_size(get_window_size());
     }
 
     let mut input = WinitInputHelper::new();
     let mut pixels = {
+        #[cfg(not(target_arch = "wasm32"))]
         let window_size = window.inner_size();
+
+        #[cfg(target_arch = "wasm32")]
+        let window_size = get_window_size().to_physical::<u32>(window.scale_factor());
+
         let surface_texture =
             SurfaceTexture::new(window_size.width, window_size.height, window.as_ref());
-        Pixels::new_async(WIDTH, HEIGHT, surface_texture)
-            .await
-            .expect("Pixels error")
+        let builder = PixelsBuilder::new(WIDTH, HEIGHT, surface_texture);
+
+        #[cfg(target_arch = "wasm32")]
+        let builder = {
+            // Web targets do not support the default texture format
+            let texture_format = pixels::wgpu::TextureFormat::Rgba8Unorm;
+            builder
+                .texture_format(texture_format)
+                .surface_texture_format(texture_format)
+        };
+
+        builder.build_async().await.expect("Pixels error")
     };
     let mut world = World::new();
 
     let res = event_loop.run(|event, elwt| {
-        // Draw the current frame
-        if let Event::WindowEvent {
-            event: WindowEvent::RedrawRequested,
-            ..
-        } = event
-        {
-            world.draw(pixels.frame_mut());
-            if let Err(err) = pixels.render() {
-                log_error("pixels.render", err);
-                elwt.exit();
-                return;
-            }
-        }
+        match event {
+            Event::WindowEvent {
+                event: WindowEvent::RedrawRequested,
+                ..
+            } => {
+                // Draw the current frame
+                world.draw(pixels.frame_mut());
+                if let Err(err) = pixels.render() {
+                    log_error("pixels.render", err);
+                    elwt.exit();
+                    return;
+                }
 
-        // Handle input events
-        if input.update(&event) {
-            // Close events
-            if input.key_pressed(KeyCode::Escape) || input.close_requested() {
-                elwt.exit();
-                return;
+                // Update internal state and request a redraw
+                world.update();
+                window.request_redraw();
             }
 
-            // Resize the window
-            if let Some(size) = input.window_resized() {
+            Event::WindowEvent {
+                event: WindowEvent::Resized(size),
+                ..
+            } => {
+                // Resize the window
                 if let Err(err) = pixels.resize_surface(size.width, size.height) {
                     log_error("pixels.resize_surface", err);
                     elwt.exit();
                     return;
                 }
             }
 
-            // Update internal state and request a redraw
-            world.update();
-            window.request_redraw();
+            _ => (),
+        }
+
+        // Handle input events
+        if input.update(&event) && (input.key_pressed(KeyCode::Escape) || input.close_requested()) {
+            elwt.exit();
         }
     });
     res.unwrap();