AMD FidelityFX SSSR provides an open source library to easily integrate stochastic screen space reflections into your game.

The term “Screen Space Reflections” describes an effect that can create realistic looking reflections purely based on information already present in the rendered image. The underlying algorithm shoots reflection rays from a depth imprint of the rendered scene (a so-called “depth buffer”) and follows them in constant steps through the image until these rays intersect with the depth buffer again. Instead of taking constant-sized steps, FidelityFX SSSR builds on an industry-leading algorithm that searches the rendered image in a hierarchical manner. This allows for larger and fewer steps on average, increasing performance of the search and quality of the final image.

To support glossy reflections, this FidelityFX effect jitters the reflection rays to create the sense of surfaces with varying roughness. However, that approach inherently introduces noise. Thus, AMD FidelityFX SSSR comes with a high quality denoiser specifically optimized for the RDNA™ architecture. The denoiser combines the results from multiple frames to create a noise-free image. Furthermore, it allows the ray count to decrease based on surface roughness, thus further speeding up screen space traversal.