From the documentation:
BumpOffset materials use a grayscale heightmap to give depth information. The brighter the value in the heightmap, the more ‘popped out’ the material will be; these areas will parallax (shift) as a camera moves across the surface. Darker areas in the heightmap are ‘further away’ and will shift the least.
I need a concave feature on an object, and pushing every part of the texture out but the concave feature in order to fake it isn’t an option. It seems that the default behavior of the node disallows it from being used to ‘indent’ areas, for example, by plugging in a minus value into the Height, but this is exactly what I need.
Is there any node that is designed to do this, or way to modify the BumpOffset node to do this?
Thanks!