The add() to the existing tint()

I’m recreating my zombie survivial game from scratch, and one major thing I am adding is night vision goggles you can “buy” Ingame.

The tint function is ok, I suppose, but is there any way to make a function that adds instead of subtracting like tint does? I know this would result in whited out areas- that’s exactly the effect I am looking for.

You could try over-brightening the original images and tinting down to “normal.”. Not ideal, of course. Hard to see how you can do so without bleeding out details.

can you draw on top of the image with low alpha?

I’m doing 3d rendering- and I’ve developed a system that’s very efficient. I’d rather not double the number of sprites I have to draw.