app,gpu: move errDeviceLost from package app to package gpu

The Vulkan backend can return device lost error from more than just
Present.

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

app/d3d11_windows.go

@@ -70,7 +70,7 @@ func (c *d3d11Context) Present() error {
 			// Ignore
 			return nil
 		case d3d11.DXGI_ERROR_DEVICE_RESET, d3d11.DXGI_ERROR_DEVICE_REMOVED, d3d11.D3DDDIERR_DEVICEREMOVED:
-			return errDeviceLost
+			return gpu.ErrDeviceLost
 		}
 	}
 	return err

app/os.go

@@ -113,11 +113,6 @@ type context interface {
 	Unlock()
 }
 
-// errDeviceLost is returned from Context.Present when
-// the underlying GPU device is gone and should be
-// recreated.
-var errDeviceLost = errors.New("GPU device lost")
-
 // Driver is the interface for the platform implementation
 // of a window.
 type driver interface {

app/window.go

@@ -153,7 +153,7 @@ func (w *Window) validateAndProcess(frameStart time.Time, size image.Point, sync
 			})
 			if err != nil {
 				w.destroyGPU()
-				if err == errDeviceLost {
+				if errors.Is(err, gpu.ErrDeviceLost) {
 					continue
 				}
 				return err
@@ -175,7 +175,7 @@ func (w *Window) validateAndProcess(frameStart time.Time, size image.Point, sync
 		if w.gpu != nil {
 			if err := w.render(frame, size); err != nil {
 				w.destroyGPU()
-				if err == errDeviceLost {
+				if errors.Is(err, gpu.ErrDeviceLost) {
 					continue
 				}
 				return err

gpu/api.go

@@ -28,3 +28,7 @@ type Direct3D11 = driver.Direct3D11
 
 // Metal denotes the Apple Metal API.
 type Metal = driver.Metal
+
+// ErrDeviceLost is returned from GPU operations when the underlying GPU device
+// is lost and should be recreated.
+var ErrDeviceLost = driver.ErrDeviceLost

gpu/internal/driver/driver.go

@@ -54,6 +54,8 @@ type Device interface {
 	Release()
 }
 
+var ErrDeviceLost = errors.New("GPU device lost")
+
 type LoadDesc struct {
 	Action     LoadAction
 	ClearColor f32color.RGBA