Most of my work was optimizing raymarching techniques for fractal geometry in stereo rendering, and also finding/combining cool fractals in an art-directable manner.
Among the tricks we implemented were two key ones: one is conemarching, a hierarchical raymarching technique that had previous literature. The other is stereo reprojection – we found a way to extend existing reprojection techniques designed for rasterization and solve the gap filling problem given that we’re using SDFs and raymarching.
In the end, we could render at 90hz by just rendering one eye and reprojecting on a GTX1080Ti, while keeping correct stereo geometry and shading.
We published this both at VRDC@GDC, and at Siggraph.
You can check out the GDC slides here: GDC Vault Link
We also found a way to improve the Mandelbulb’s SDF formula to reduce bubbles of overestimation. You can check out a demo here:
You can press and move the bar on the screen to see before/after. There’s more information on the shadertoy, check it out!