RTX Coffee Break: Ray Traced Ambient Occlusion (4:17 minutes)

SSAO (Screen Space Ambient Occlusion) is popular, but a limited process being used in contemporary games. Ray tracing provides better results. We explain why, and prove it with a set of side-by-side examples.

Five Things to Remember:

  • SSAO is a less-than-ideal process: it darkens the corners and edges in a scene, and leaves a dark halo around object borders.
  • SSAO also can’t handle occlusion from offscreen geometry (or in-screen geometry, but occluded).
  • Actually tracing rays around the geometry in the scene will be more physically correct than SSAO and gives you higher visual quality.
  • Direct comparison between 2spp [2 sample per-pixel] Denoised and Ground Truth are strikingly close. SSAO is clearly less convincing.
  • 1spp works pretty well for far-field occlusion, but for near field contact, we need to get to at least 2spp.

You can find six additional coffee-break length videos about ray tracing in games with RTX on the NVIDIA developer blog.