Color Shadows

[flowerdealer]

Hi, I'm trying to get opaque colored shadows projected into other geometry. So far I've gotten this result by using transparent geometry with a vex layered surface attached with the alpha set to 0 and the transmit value set to whatever color I choose. I get the expected result if I'm projecting over an object shaded in white, but if I change the color it mixes with the new color. I tried to create a new shader in VOPS that uses the shadow matte to cut out the color from the region I want to maintain for the opaque shadows, but the problem is that because I set the layered texture's alpha to 0 in the projecting object, the alpha is black.

How else could I do this?

I have seen the Ubershadow shader, but I would like to be able to color the shadows based on the color of projecting objects, not some arbitrary values. Any help would be much appreciated.

[edward]

Try just directly using a Is Shadow Ray VOP instead of the Shadow Matte VOP. Something like this:

Is Shadow Ray -> Integer to Float -> Complement -> Output (Af)

[flowerdealer]

Hi, I've tried doing what you're saying but the shader doesn't evalutae as an opaque black and white matte. Again, I'm using filtered shadows with the casting object using a material with a certain transmission color, and 0 alpha. Am I doing something wrong?

[edward]

Hmm ... it looks like a ray is not considered as "shadow" if it's being transmitted through a transparent surface. What about doing your rendering in multiple passes then?

Pass 1: White receiver objects receiving the coloured shadows

Pass 2: Opaque Shadows with alpha = 1 with a shader that just does the Is Shadow Ray part.

Then you can use the alpha from pass 2 with pass 1?

[flowerdealer]

Yes, I guess I could always do that, although I'm trying to learn vex shading in vops and was trying to figure it out. Any other ideas? Thanks for your help anyway!