Dynamic Paint Alpha

Hey all,

I have searched high and low for a solution, but I cannot seem to find it. That or I do not know how to ask the question.

I understand Dynamic Paint basics, and can do simple writings with paths, some Indirect Lighting stuff, etc. What I am wanting though, and writing on Dynamic Paint is limited to writing simulations or rain or other displace sims, is to use the brush stroke to create an alpha channel, for lack of a better word. Hmmm…Say I have an image on a plane and cover it with another color or texture. Then do some strokes with the brush and it erases that color. I am thinking I can use erase, but I have no clue on how to do that. And the idea I have of it -use DP to paint the plane, then erase it.

When doing the indirect lighting sims, you have seen them. with the glowing strokes. I have figured out to create a mask, then on another plane add the glowing material. I have tried that, without the glowing material and using an image texture, but for reasons I do not understand it will not render. Yes, I turned off indirect lighting. Nothing renders, no planes what-so-ever.

Trying to figure this out on my own leads to many head-bangs against the wall. Any ideas? My head is getting sore!

Thanks

BH

Nevermind. Got it. All about clicking Invert.