You only need a black and white image as the mask. You can ‘channel pack’, but you don’t have to.
It also doesn’t matter which way around you have the image ( black / white ), because you can always invert the sign in the material.
You only need a black and white image as the mask. You can ‘channel pack’, but you don’t have to.
It also doesn’t matter which way around you have the image ( black / white ), because you can always invert the sign in the material.