app,internal/vk: [Vulkan] skip frame with stale window dimensions

While here, add a missing nil check.

Updates gio#280

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

app/os.go

@@ -22,6 +22,10 @@ type size struct {
 	Height unit.Value
 }
 
+// errOutOfDate is reported when the GPU surface dimensions or properties no
+// longer match the window.
+var errOutOfDate = errors.New("app: GPU surface out of date")
+
 // Config describes a Window configuration.
 type Config struct {
 	// Size is the window dimensions (Width, Height).

app/vulkan.go

@@ -104,7 +104,13 @@ func mapErr(err error) error {
 		// swapchain (preTransform != currentTransform). However, we don't
 		// support transforming the output ourselves, so we'll live with it.
 		return nil
-	case vkErr.IsDeviceLost():
+	case vkErr == vk.ERROR_OUT_OF_DATE_KHR:
+		return errOutOfDate
+	case vkErr == vk.ERROR_SURFACE_LOST_KHR:
+		// Treating a lost surface as a lost device isn't accurate, but
+		// porbably not worth optimizing.
+		return gpu.ErrDeviceLost
+	case vkErr == vk.ERROR_DEVICE_LOST:
 		return gpu.ErrDeviceLost
 	}
 	return err
@@ -149,6 +155,16 @@ func (c *vkContext) refresh(surf vk.Surface, width, height int) error {
 	vk.DeviceWaitIdle(c.dev)
 
 	c.destroyImageViews()
+	// Check whether size is valid. That's needed on X11, where ConfigureNotify
+	// is not always synchronized with the window extent.
+	caps, err := vk.GetPhysicalDeviceSurfaceCapabilities(c.physDev, surf)
+	if err != nil {
+		return err
+	}
+	minExt, maxExt := caps.MinExtent(), caps.MaxExtent()
+	if width < minExt.X || maxExt.X < width || height < minExt.Y || maxExt.Y < height {
+		return errOutOfDate
+	}
 	swchain, imgs, format, err := vk.CreateSwapchain(c.physDev, c.dev, surf, width, height, c.swchain)
 	if c.swchain != 0 {
 		vk.DestroySwapchain(c.dev, c.swchain)

app/vulkan_android.go

@@ -57,7 +57,9 @@ func (c *wlVkContext) API() gpu.API {
 
 func (c *wlVkContext) Release() {
 	c.ctx.release()
-	vk.DestroySurface(c.inst, c.surf)
+	if c.surf != 0 {
+		vk.DestroySurface(c.inst, c.surf)
+	}
 	vk.DestroyInstance(c.inst)
 	*c = wlVkContext{}
 }

app/window.go

@@ -152,6 +152,11 @@ func (w *Window) validateAndProcess(frameStart time.Time, size image.Point, sync
 				err = w.ctx.Refresh()
 			})
 			if err != nil {
+				if errors.Is(err, errOutOfDate) {
+					// Surface couldn't be created for transient reasons. Skip
+					// this frame and wait for the next.
+					return nil
+				}
 				w.destroyGPU()
 				if errors.Is(err, gpu.ErrDeviceLost) {
 					continue
@@ -174,6 +179,11 @@ func (w *Window) validateAndProcess(frameStart time.Time, size image.Point, sync
 		}
 		if w.gpu != nil {
 			if err := w.render(frame, size); err != nil {
+				if errors.Is(err, errOutOfDate) {
+					// GPU surface needs refreshing.
+					sync = true
+					continue
+				}
 				w.destroyGPU()
 				if errors.Is(err, gpu.ErrDeviceLost) {
 					continue