From left: Our approach with one sample per pixel, 5.83 min. 8×8 samples per pixel, 11.35 min. 16×16 samples per pixel, 47.42 min. Our approach achieves a smooth result while others are noisy regardless of many samples. Right: Reflection/refraction is also supported.
The “curves” primitive provides a way to define ribbon-like objects such as fur and hair. Accurate and efficient rendering of fur/hair is very important for VFX/CG animation industries. But ray tracing such thin primitives is a difficult problem.
We propose distance-aware ray tracing for curves, and combine it with the concept of an A-buffer for smooth rendering with low samples. “Distance-aware” means that the method can support not only actual intersections but also distances to curves. Our approach achieve a smooth rendering of thin curves even while less computation time.