Powerplant benchmark: Our selective ray tracing algorithm can render the 12.7M triangle Powerplant model at 16 fps with hard shadows (left) and over 2 fps with soft shadows with 16 light samples (right) running on a NVIDIA GTX 280 GPU.

Abstract
We present novel algorithms to achieve interactive high-quality illumination with hard and soft shadows in complex models. Our approach combines the efficiency of rasterization-based approaches with the accuracy of a ray tracer. We use conservative image-space bounds to identify only a small subset of the pixels in the rasterized image and perform selective ray tracing on those pixels. The algorithm can handle moving light sources as well as dynamic scenes. In practice, our approach is able to generate high quality hard and
soft shadows on complex models with millions of triangles at almost interactive rates on current high-end GPUs.

Quality comparison

Please see the Appendix (PDF) for high-resolution images.

Hard shadows


Soft shadows