How to color PointLights from a GPU texture?

I’m trying to assign colors to the lights in my scene - by passing it a texture directly from the GPU.

Example: We have a populated scene that is being lit up by 6 PointLights.
The goal is to have these 6 PointLights reference pixel values for their light color, directly from a texture/buffer map that is running a RTT animation (aka a pixelshader/quadshader).

Is there anyway to do this in Three.js?