I have a character in a video masked out, and overlayed ontop of its original self. I dyed the masked version red, so they look like they fell in paint. I want to have rain falling down in the background, which can be done via an overlay for example, but I want the rain to create streaks that wipe off the red and go back to the underneath mask. Is there an easy way to do this? Like if I could turn an overlay of rain into a mask for example...?
The only way I can see to do this atm is to make a mask for every single streak of rain going down the character...fading back to the original colour. Is there a more efficient way to get a kinda rain streak effect, I'd want the character to return to the original colour (mask gone type of a thing) after a little bit. Like with multiply with a rain overlay but inverted and overlayed...? I can't even invert a multiply though much less overlay it in blender.