Beast Lightmaps to Vertex Colors in Unity (with texture blend support)

This started out as a little script that I got interested in and decided to flesh out and do a video for.

The basic idea here is to store Beast-generated lightmaps as vertex colors. That by itself is very simple: iterate over the object’s vertices and for each one, get the interpolated value of the lightmap at that vertex’s uv2 coordinate, and store that RGBA value as the vertex color at that location. To make these new vertex colors useful, a shader must treat the vertex colors the way it would otherwise have treated the lightmap values.

The problem here is that you’re giving up all of your vertex color channels to store this lightmap information. You could get around this issue a few ways, but the solution presented here is to copy the original vertex colors, and after you are done with the lightmap conversion, store the first two vertex color channels (RG of RGBA) into UV2. Since UV2 is unnecessary now that the lightmap has been stored as vertex colors, that’s technically a Vector2 array which is available to shaders that isn’t being used for anything.

As you can see in the video, there are a few ways of organizing this general form of solution. At its core, it’s really just a question of storing useful information somewhere a shader can read it, and writing a compatible shader. That covers too much ground, so a working, fairly intuitive, holistic example provided in the project archive which absolutely does work and should (hopefully!) be useful for mobile or web developers.

Project archive:
http://www.vertexcolors.com/shared/unity_beast_to_vertex_colors_deep.zip

Full post:
http://vertexcolors.com/?p=60

Cheers,
-abm

 

Thank You for sharing developement! Maybe I will explore this feature in a while.

 

Interesting project! Thanks for sharing with us hausmaus

 

Another reason to take a look at shader programming. Good work sir, this looks SUPREMELY useful!
Thank you.

 

Clever approach

 

Like it.

 

nice share

 

Anyone have a copy of the scripts? The website is down.