Soft Shadow Rendering Algorithm Based on GPU’s Shadow Line

doi:10.16182/j.issn1004731x.joss.201804009

Abstract

Abstract: To solve the problem of soft shadow rendering algorithm on shaded body surfaces, a new algorithm based on shadow lines which can render better soft shadow with less cost computation overhead is presented. GPU is used to create shadow lines which include starting point, ending point and shading value. The computer shader (CS) is used to amend the shading value by inverse distance weighting function. In the phase of shadow rendering, the shadow lines dataset is used to calculate the current pixel's shading value by trigonometric interpolation. Experimental result shows that the algorithm can solve the soft shadow rendering problem effectively. It can not only meet the needs of real-time rendering, but also give out the flexible and adjustable soft shadows.

Key words: shaded bodies, geometric shader, computer shader, soft shadow rendering

CLC Number:

TP391

Gao Shanxiao, Wu Xian. Soft Shadow Rendering Algorithm Based on GPU’s Shadow Line[J]. Journal of System Simulation, 2018, 30(4): 1279-1286.

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