Mirror/Glitch Lab's 'Topology 3D' in TouchDesigner


Mirror Lab and Glitch Lab are very popular Android apps for making procedural art, and they have an effect called 'Topology 3D' which originally inspired me to dive into TouchDesigner and one day implement it - and here we are.

This Geo component takes an input texture and separates it into bands based on pixel thresholds (very similar to Threshold TOP) and distributes these bands onto different layers (instances) of a SOP geometry. The algorithm is such (by default) that each layer’s texture is also subtracted from the consecutive ones, meaning if you added the layer textures the result would be the original texture. 

The effect is analogous to a Phong’s height map, except in this case the XY resolution is “infinite” and the Z is defined by the number of SOP layers (that can be arbitrarily low detail), whereas with a Phong height map the Z is “infinite” and the XY is defined by the SOP detail (which must be high to get good looking results).