Can I lay a fixed layer over a custom canvas?

In Android Studio, I'm developing a game in which I draw my animation at 60fps using a SurfaceView object. I use a semitransparent image as the top layer to hide the edges of the playing field -- sort of a "fogs of war" effect so that the player does not know what to expect beyond the shadows.

My problem is that I need to draw this shadow image for every frame, even though the shadow never changes or moves, even when the playing field scrolls right/left/up/down. And it's a full-screen image, so it slows the game to a crawl.

Is there a way to create a one-time overlay ONCE on top of the animated custom canvas? I also want to interact with the canvas beneath it, as if the overlay was not even there.

Have you tried putting a full screen ImageView over your surface view and setting the "fog of war" image to this, should draw it once (this is assuming the background to your "fog of war is transparent").

If you need anything fancier then ViewOverlay should cover you, but my understanding is this is used when individual views wish to draw outside their bounds for animations, as you are using full screen surface view this should be unnecessary

https://developer.android.com/reference/android/view/ViewOverlay.html

Also no reason why you can't stick a surface view over a surface view. One for the fog of war / screen effects, one for the game surface.