Is it at all possible to specify a glow map with cycles, so that I can apply a glow/bloom shader effect post-process in the compositor?
You can use a texture as the factor input of a mix shader, mixing your object material with an emission shader
Glow maps are simply black and white maps that specify where to apply post-production filters in the game engine. The equivalent in an offline renderer like Cycles would be using a black and white map to blend between an emission shader and another shader(s) and then doing blur/glow in the compositor. That type of glow is not something you determine in modeling/material setup, it’s all done in post.
The problem though, is that I’m working with a node setup that uses blended emissive+diffuse to accomplish toon shading Though, now I think I have enough information to figure this out: just base the post-process glow on areas that have more than 50% emissive.
Okay, unfortunately this didn’t work, as the compositor obtained the color data for emissive surfaces, rather than a percentage value. So, basing a glow/bloom shader off of emissive is a no-go.
Is there any way I can pass custom data to the compositor?
Okay, I’ll ask again, is there a way to perform a blur/bloom glow effect in the cycles compositor WITHOUT making any use of the emissive property?