Relief Bump Effect

Standard (normal) bump effect simply adjusts the surface normals to modify reflections and shadows. In order to achieve better bump effect, you need to use different algorithms. Owlet implements relief bump algorithm that works perfectly fine for flat surfaces. Here you can see the difference:

The difference between normal and relief bump effects in Owlet

The simple bump is on the left, while the relief bump is on the right. Note that the effect just simulates relief and doesn’t really subdivide surface or adds some extra geometry, instead it performs some extra calculations when ray hits the surface to make it looks not that flat. The drawback is that the algorithm requires the surface to be completely flat. You can still use this on non-flat surfaces, but the result is unpredictable.

Let’s start with a new scene and a simple plane object:

Simple plane object in Owlet

You will need a bump texture, we’ll be using this one:

Heightmap texture we'll be using for testing bump

Now open the material properties of the material assigned to the plane and load the texture into the bump slot. Then adjust the bump level to 1 (this means 1 centimeter):

Relief bump loaded to Owlet material

That’s basically all. You define the bump level in centimeters, making sure the object is flat and Owlet does the rest. Try to avoid really large bump levels in order to keep the image realistic, as the plane itself is still flat, so too much relief will not look natural.