A monochrome relief
texture is rendered by the Sharp Emboss function. The light source
is always located in the upper-left corner of the texture.
The Heightmap contains
the relief data, which is needed to calculate the emboss effect.
If you keep applying the function to the same texture with a high Pre-Smoothing
(and Amplify) value, you can create a sand stripe pattern
like visible in Image 3.
Regulate the contrast of the new
texture with the Amplify value.