CUDA based volumetric path tracing for rendering heterogeneous and chromatic volumes. Using multiple techniques to accelerate the process, including reduced scattering coefficients[1][2] and spectral and decomposition tracking[3] with local density bounds.
The vdbloader utility requires installing the OpenVDB library and its dependencies, and can be used to read the volumetric cloud data from WDAS.
Convergence takes roughly 30 seconds on GTX 1080 with 1k samples per pixel.
If built without OpenVDB support, a procedural Julia Set is used.
[1] Jensen et al., A Practical Model for Subsurface Light Transport
[2] Burley et al., The Design and Evolution of Disney's Hyperion Renderer
[3] Kutz et al., Spectral and Decomposition Tracking for Rendering Heterogeneous Volumes