Over the past months, we've pushed various improvements to our implementation of Dynamic Diffuse Global Illumination (DDGI), which result in faster and improved raytraced realtime GI (based on software tracing SDFs). Long-standing issue with color shift towards yellow was fixed, and indirect shadow areas now have higher contrast. Probes sampling algorithm has been refactored to support fallback probes when drawing pixels in areas without nearby GI information. This fixes lighting on smoke particles or characters in large rooms or open-world maps where GI probes are placed far from lit objects.
On the topic of rendering, Screen Space Reflections tracing has been refactored to use Hi-Z buffer and more optimized combine pass, which greatly improves its performance. Also, we've managed to reduce resolution of Volumetric Fog while maintaining its quality by performing better temporal sampling and filtering. As a result, Flax Tech Demo 2022 gets about 10% perf boost.