add SurfaceTargetUnsafe::from_window utility

wgpu/src/lib.rs

@@ -534,6 +534,24 @@ pub enum SurfaceTargetUnsafe {
  SwapChainPanel(*mut std::ffi::c_void),
 }
 
+impl SurfaceTargetUnsafe {
+ /// Creates a [`SurfaceTargetUnsafe::RawHandle`] from a window.
+ ///
+ /// # Safety
+ ///
+ /// - `window` must outlive the resulting surface target
+ /// (and subsequently the surface created for this target).
+ pub unsafe fn from_window<T>(window: &T) -> Result<Self, raw_window_handle::HandleError>
+ where
+ T: HasDisplayHandle + HasWindowHandle,
+ {
+ Ok(Self::RawHandle {
+ raw_display_handle: window.display_handle()?.as_raw(),
+ raw_window_handle: window.window_handle()?.as_raw(),
+ })
+ }
+}
+
 /// Handle to a binding group layout.
 ///
 /// A `BindGroupLayout` is a handle to the GPU-side layout of a binding group. It can be used to
@@ -1881,29 +1899,16 @@ impl Instance {
 
  let target = target.into();
  let mut surface = match target {
- SurfaceTarget::Window(window) => {
- let raw_display_handle = window
- .display_handle()
- .map_err(|e| CreateSurfaceError {
- inner: CreateSurfaceErrorKind::RawHandle(e),
- })?
- .as_raw();
- let raw_window_handle = window
- .window_handle()
- .map_err(|e| CreateSurfaceError {
+ SurfaceTarget::Window(window) => unsafe {
+ let surface = self.create_surface_unsafe(
+ SurfaceTargetUnsafe::from_window(&window).map_err(|e| CreateSurfaceError {
  inner: CreateSurfaceErrorKind::RawHandle(e),
- })?
- .as_raw();
-
+ })?,
+ );
  handle_origin = Some(window);
 
- unsafe {
- self.create_surface_unsafe(SurfaceTargetUnsafe::RawHandle {
- raw_display_handle,
- raw_window_handle,
- })
- }?
- }
+ surface
+ }?,
 
  #[cfg(any(webgpu, webgl))]
  SurfaceTarget::Canvas(canvas) => {