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.

About Brad Nemire

Brad Nemire leads the Developer Communications team at NVIDIA focused on evangelizing amazing GPU-accelerated applications. Prior to NVIDIA, he worked at Arm on the Developer Relations team. Brad graduated from San Diego State University.