21. Ray tracing of a beam of light passing through a medium with changing refractive index.22. Ray tracing , if it is limited to Whitted's algorithm, is not necessarily the most realistic.23. Conventional ray tracing also typically spawns one reflection ray and one transmission ray per intersection. 24. Historically, RenderMan used the ray tracing and global illumination. 25. This partitioning can be used for the efficient implementation of virtual drivethroughs and ray tracing . 26. The first ray tracing algorithm used for rendering was presented by Arthur Appel in 1968. 27. However, unlike the majority of ray tracing technique. 28. At SIGGRAPH 2009, Nvidia announced OptiX, a free API for real-time ray tracing on Nvidia GPUs. 29. Arnold is based on Monte Carlo Ray Tracing . 30. For each pixel, the scene is ray traced until the closest surface of intersection is found.
