app/internal/windows,app/internal/d3d11: ensure error is returned

d3d11Context.Present would return a nil error if the underlying error
d3d11.ErrorCode.

While here, use defer for a resource cleanup.

Signed-off-by: Elias Naur <mail@eliasnaur.com>

app/internal/d3d11/backend_windows.go

@@ -258,19 +258,19 @@ func NewBackend(d *Device) (*Backend, error) {
 		caps.MaxTextureSize = 4096
 	}
 	b := &Backend{dev: d, caps: caps}
+	// Enable depth mask to match OpenGL.
+	b.depthState.mask = true
 	// Disable backface culling to match OpenGL.
 	state, err := b.dev.dev.CreateRasterizerState(&_D3D11_RASTERIZER_DESC{
 		CullMode:        _D3D11_CULL_NONE,
 		FillMode:        _D3D11_FILL_SOLID,
 		DepthClipEnable: 1,
 	})
-	// Enable depth mask to match OpenGL.
-	b.depthState.mask = true
 	if err != nil {
 		return nil, err
 	}
+	defer _IUnknownRelease(unsafe.Pointer(state), state.vtbl.Release)
 	b.dev.ctx.RSSetState(state)
-	_IUnknownRelease(unsafe.Pointer(state), state.vtbl.Release)
 	return b, nil
 }
 

app/internal/window/d3d11_windows.go

@@ -46,18 +46,20 @@ func (c *d3d11Context) Backend() (backend.Device, error) {
 }
 
 func (c *d3d11Context) Present() error {
-	if err := c.swchain.Present(); err != nil {
+	err := c.swchain.Present()
-		if err, ok := err.(d3d11.ErrorCode); ok {
+	if err == nil {
-			switch err.Code {
+		return nil
-			case d3d11.DXGI_STATUS_OCCLUDED:
+	}
-				// Ignore
+	if err, ok := err.(d3d11.ErrorCode); ok {
-				return nil
+		switch err.Code {
-			case d3d11.DXGI_ERROR_DEVICE_RESET, d3d11.DXGI_ERROR_DEVICE_REMOVED, d3d11.D3DDDIERR_DEVICEREMOVED:
+		case d3d11.DXGI_STATUS_OCCLUDED:
-				return ErrDeviceLost
+			// Ignore
-			}
+			return nil
+		case d3d11.DXGI_ERROR_DEVICE_RESET, d3d11.DXGI_ERROR_DEVICE_REMOVED, d3d11.D3DDDIERR_DEVICEREMOVED:
+			return ErrDeviceLost
 		}
 	}
-	return nil
+	return err
 }
 
 func (c *d3d11Context) MakeCurrent() error {