A practical and fast rendering algorithm for dynamic scenes using adaptive shadow fields

Recently, a precomputed shadow fields method was proposed for achieving fast rendering of dynamic scenes under environment illumination and local light sources. This method can render shadows fast by precomputing the occlusion information at many sample points arranged on concentric shells around each object and combining multiple precomputed occlusion information rapidly in the rendering step. However, this method uses the same number of sample points on all shells, and cannot achieve real-time rendering due to the rendering computation rely on CPU rather than graphics hardware. In this paper, we propose an algorithm for decreasing the data size of shadow fields by reducing the amount of sample points without degrading the image quality. We reduce the number of sample points adaptively by considering the differences of the occlusion information between adjacent sample points. Additionally, we also achieve fast rendering under low-frequency illuminations by implementing shadow fields on graphics hardware.

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