Volumetric Light Transfer in Functionally Defined Scenes

Abstract

In computer graphics, the main goals are high realism and rendering speed. In terms of realism, physically correct rendering is important, which calculates the transmission of light from the source to the observer. A method of modeling global illumination is presented, which takes into account light coming directly from sources, as well as light redirected through other parts of the scene. This allows you to create various optical effects, such as the flow of color from one surface to another, indirect lighting and caustics. The photon display method is designed for functionally defined scenes using graphics processors, thereby achieving an interactive rendering mode. The aim of the work is to implement a method for displaying photons in interactive rendering mode using graphics processors. It was necessary to find a compromise between physical accuracy and the speed of displaying scenes. As the number of parallel computing cores increases, traditional programming models become less efficient. GPUs based on the parallel processing model are being expanded by adding improved support for general-purpose computing to their cores. CUDA is a multicore computing platform. GPU-enabled hardware provides low-cost access to many computations. The method presented in this paper extends the photon-mapping algorithm for the CUDA platform to volumetric photon mapping. The beam brightness estimate used to efficiently calculate the density is recovered with the correct physical parameters. Photons are traced and bandwidth is selected. Performance increases due to calculations on multiple cores and the use of large compacted blocks.