in 2013 I was inspired by the old MS-DOS game Comanche to try my hand at a 3d Voxel renderer. The system uses a heightmap and raycasting to efficiently render a detailed 3d landscape.
Firstly I wrote a software renderer for x86 using C++11 and SSE instructions. Realizing the algorithm was embarrassingly parallelizable, I quickly followed this up with an OpenCL based renderer to take advantage of massively parallel GPUs.