Method for precalculating radiancy transfer full-frequency shadow based on GPU

Abstract

A method of transferring entire frequency shadow owing to the pre-computed radiancey of GPU, (1) making use of the circumstance illuminance image to pursues the illumination to circumstance , getting the radiation delivery function B = TL, matrix T is radiation delivery matrix, L is an illuminant matrix; (2) pre-computing the radiation delivery matrix T; (3)getting sparse radiation delivery matrix when the pre-computed radiation delivery matrix T compressed in quantization owe to small echo alternation; (4) rearranging the sparse radiation delivery matrix in (3) to put the important matrix in the front part; (5) doing small echo alternation rapidly for L, getting sparse illuminant matrix which has been quantization compressed; (6) carrying out rapidly sparse matrix multiplication on T and L in GPU to accomplish the re illumination exaggeration. The invention make use of the data structure and algorithm according to the ability of GPU that computed in parallel, it can reach fairly good balance between CPU loads and GPU loads, exaggerating speed and exaggerating quality . It can reduce the use of memory and keep the quality of exaggerating at the same time, and the exaggerating speed has increased in wide-range. It has reached the purpose of exaggerating entire frequency shadow in real time.

Description

technical field [0001] The invention relates to a method for rendering full-frequency shadows in real time, in particular to a method for transferring full-frequency shadows based on GPU pre-calculated radiance. Background technique [0002] Photorealistic rendering has always been an important goal and direction pursued by computer graphics. The scene's natural light source heavy lighting and complex light transfer phenomena are applied to various environments such as simulation, education, and entertainment, which can greatly improve the realism and immersion of rendering. Among light transfer phenomena, shadow is a common and very important phenomenon. In the process of users' perception of 3D scenes, shadows play an important role in the human brain's reconstruction of scene object shape, object depth and other information, so it is more and more used in CG, virtual reality, 3D games and other environments. [0003] Shading algorithm has an important position and a lon...

AI Technical Summary

Problems solved by technology

Although this method achieves real-time rendering, it requires a large amount of memory, and still requires a considerable amount of calculation at runtime, which places a heavy load on the CPU

And because this method uses a nonlinear wavelet calculation method, the core calculation is multiplication between a sparse matrix and a sparse vector, so it cannot be accelerated by GPU

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