Kretzschmar, V., Meyer, B., Hergenröhter, E.
Abstract:
This paper introduces a new algorithm for real-time rendering based on bidirectional path tracing, reservoir-based spatio-temporal importance resampling (ReSTIR), and dynamic diffuse global illumination (DDGI).
The combination of these algorithms produce an image with reduced noise compared to real-time algorithms like path training, while retaining details like caustics.
Also, unlike standard ray tracing and bidirectional path tracing, our approach does not suffer from darkening due to random light source selection.
Reservoir-based spatio-temporal importance resampling eliminates darkening due to random light source selection, but does not improve ray tracing in terms of rendering speed.
Dynamic diffuse global illumination efficiently estimates global illumination, enhanced by ReSTIR for improved quality. However, DDGI does not simulate refraction and transparency.
In this paper the combination of bidirectional path tracing, DDGI and ReSTIR is proposed.
This balances the described drawbacks of these algorithms.
Our approach is capable of running in real time in acceptable quality while supporting refraction.
All algorithms discussed in the paper are run in real-time and the quality is compared by using measurements for darkening and the similarity to an offline path-traced result.?