This may be a stupid question but I don't understand the concept behind vertex colors:
What is vertex painting? Essentially it’s blending several textures depending on the mesh’s vertex colors. Since vertex colors are linearly interpolated you get a smooth result.
I know that if I have a color vector in the vertex shader and push it to the pixel shader the values get interpolated, but where does the vertex color come from? Is it a regular tex2D operation in the vertex shader? If yes/ no, is it possible in acknex?