Multiple masks affecting a single sprite

Hello! I'm looking for a simple way for multiple Sprite Masks to affect a single sprite (ideally just using the basic SpriteMask component).

From what I can see, sprites can only use one mask at a time. Does anyone know another way? I've tried stacking multiple masks but that doesn't seem to work.

The effect I'm trying to achieve is a large tiling texture border covering the screen, with a rectangular hole cut out of the middle. Then *all* of this image should be hidden, except for a circle that's centred around the player.

The result should be that this large tiling rectangular level border should be visible only when the player moves near it, like this:



The problem I have with my current setup is that the hazard stripe edges are made of multiple sprites, and there are visible seams and tiling issues. My level size has to be a particular, irregular weird size which is difficult to tile cleanly, and I can't change that.

Any help appreciated!

 

Wait - how are you planning on using multiple masks to fix your tiling problem?