Is it possible to control the vertex color (directly the color or just the intensity of the color) with shapekeys ?
For example I have the “mouth_happy” shapekey set to 0.
When I set it to 1, because it plays with the corners of the mouth, i want the vertex color in this region to become white or to have the intensity to 1.
Because this system allows me to have only 2 normal maps and a better optimization in UE4. One standard and one for every expression deformations combined. So if the vertex color only appears when the shapekey is activated i can get better details without using a NM for each one of them.