issue-1031: reimplement winit BadIcon error

crates/bevy_render/src/lib.rs

@@ -20,7 +20,10 @@ use bevy_ecs::{
     system::{IntoExclusiveSystem, IntoSystem, Res},
 };
 use bevy_transform::TransformSystem;
-use bevy_utils::{tracing::warn, HashMap};
+use bevy_utils::{
+    tracing::{error, warn},
+    HashMap,
+};
 use bevy_window::{WindowIcon, WindowIconBytes, WindowId, Windows};
 use draw::{OutsideFrustum, Visible};
 
@@ -274,12 +277,24 @@ fn window_icon_changed(
             match asset_server.get_load_state(handle) {
                 LoadState::Loaded => {
                     if let Some(texture) = textures.get(handle) {
-                        let window_icon = WindowIcon::from(WindowIconBytes {
-                            bytes: texture.data.clone(),
-                            width: texture.size.width,
-                            height: texture.size.height,
-                        });
-                        window.set_icon(window_icon);
+                        /* TODO: Not actually sure if we need to check the error here
+                        Whatever Texture gives us might be fine */
+                        let window_icon_bytes = WindowIconBytes::new(
+                            texture.data.clone(),
+                            texture.size.width,
+                            texture.size.height,
+                        );
+
+                        match window_icon_bytes {
+                            Ok(window_icon_bytes) => {
+                                let window_icon = WindowIcon::from(window_icon_bytes);
+                                window.set_icon(window_icon);
+                            }
+                            Err(e) => error!(
+                                "For handle {:?} the following error was produced: {}",
+                                handle, e
+                            ),
+                        }
 
                         o.remove();
                     }

crates/bevy_window/Cargo.toml

@@ -21,6 +21,7 @@ bevy_utils = { path = "../bevy_utils", version = "0.5.0" }
 bevy_asset = { path = "../bevy_asset", version = "0.5.0" }
 
 # other
+thiserror = "1.0"
 
 [target.'cfg(target_arch = "wasm32")'.dependencies]
 web-sys = "0.3"

crates/bevy_window/src/window.rs

@@ -1,5 +1,6 @@
 use bevy_math::{IVec2, Vec2};
 use bevy_utils::{tracing::warn, Uuid};
+use thiserror::Error;
 
 #[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
 pub struct WindowId(Uuid);
@@ -92,9 +93,20 @@ impl WindowResizeConstraints {
 
 #[derive(Debug, Clone)]
 pub struct WindowIconBytes {
-    pub bytes: Vec<u8>,
-    pub width: u32,
-    pub height: u32,
+    bytes: Vec<u8>,
+    width: u32,
+    height: u32,
+}
+
+#[derive(Error, Debug)]
+pub enum WindowIconBytesError {
+    #[error("32bpp RGBA image buffer expected, but {bytes_length} is not divisible by 4")]
+    NotRGBA { bytes_length: usize },
+    #[error("Buffer size {bytes_length} does not match the expected size based on the dimensions {pixel_bytes_length}")]
+    SizeMismatch {
+        pixel_bytes_length: usize,
+        bytes_length: usize,
+    },
 }
 
 #[derive(Debug, Clone)]
@@ -118,6 +130,41 @@ impl From<WindowIconBytes> for WindowIcon {
     }
 }
 
+impl WindowIconBytes {
+    pub fn new(bytes: Vec<u8>, width: u32, height: u32) -> Result<Self, WindowIconBytesError> {
+        let pixel_count = (width * height) as usize;
+        let pixel_bytes_length = pixel_count * 4;
+        let bytes_length = bytes.len();
+
+        if bytes_length % 4 != 0 {
+            Err(WindowIconBytesError::NotRGBA { bytes_length })
+        } else if pixel_bytes_length != bytes_length {
+            Err(WindowIconBytesError::SizeMismatch {
+                pixel_bytes_length,
+                bytes_length,
+            })
+        } else {
+            Ok(Self {
+                bytes,
+                width,
+                height,
+            })
+        }
+    }
+
+    pub fn bytes(&self) -> &[u8] {
+        &self.bytes
+    }
+
+    pub fn width(&self) -> u32 {
+        self.width
+    }
+
+    pub fn height(&self) -> u32 {
+        self.height
+    }
+}
+
 /// An operating system window that can present content and receive user input.
 ///
 /// ## Window Sizes

crates/bevy_winit/src/lib.rs

@@ -163,17 +163,15 @@ fn change_window(world: &mut World) {
                 bevy_window::WindowCommand::SetIcon { window_icon_bytes } => {
                     let window = winit_windows.get_window(id).unwrap();
 
-                    match Icon::from_rgba(
-                        window_icon_bytes.bytes,
-                        window_icon_bytes.width,
-                        window_icon_bytes.height,
-                    ) {
-                        Ok(winit_icon) => window.set_window_icon(Some(winit_icon)),
-                        Err(e) => {
-                            error!("Unable to create window icon: {}", e);
-                            return;
-                        }
-                    }
+                    /* Failures should already be covered in WindowIconBytes constructor */
+                    window.set_window_icon(
+                        Icon::from_rgba(
+                            window_icon_bytes.bytes().to_vec(),
+                            window_icon_bytes.width(),
+                            window_icon_bytes.height(),
+                        )
+                        .ok(),
+                    );
                 }
                 bevy_window::WindowCommand::ClearIcon => {
                     let window = winit_windows.get_window(id).unwrap();