I have written this pyramid shader in webgl by using Shadertoy.
This effect is procedural generated in a pixel (fragment) shader without any use of models.
* Procedural generated in runtime
* Ray Marching
* SDF (signed distance field)
* Menger Sponge fractal algorithm
* Soft Shadow
* 3D texture mapping by code
* AO by using the result of the ray marching process
This shader is not open source yet.