Reservoir Splatting for Temporal Path Resampling and Motion Blur

Recent extensions to spatiotemporal path reuse, or ReSTIR, improve rendering efficiency in the presence of high-frequency content by augmenting path reservoirs to represent contributions over full pixel footprints. Still, if historical paths fail to contribute to future frames, these benefits disappear. Prior ReSTIR work backprojects to the prior frame to identify paths for reuse. Backprojection can fail to find relevant paths for many reasons, including moving cameras or subpixel geometry with.