基于改进体素锥追踪的大规模场景光照计算

Illumination calculation for large-scale scene based on improved voxel cone tracking

针对大规模场景光照渲染计算量大的问题,提出一种基于改进体素锥滤波器追踪的全局光照计算算法。首先,以级联纹理结构改进简单的体素结构,实现快速高效且经各向异性过滤的场景光照信息存储,减少内存消耗;其次,基于法线加权累积计算直接光照衰减,缓解法向一致性问题;最后,基于级联纹理结构对锥波滤器进行改进,采用动态体素查找,避免整个存储结构的遍历,从而实现全局光照的高效计算。实验结果表明,改进算法在降低内存占用、提高渲染速度的同时,保持与经典体素锥追踪算法相近的渲染效果。

Aiming at the problem of large amount of global illumination calculation for large-scale scene rendering,a global illumination calculation algorithm based on improved voxel cone filter tracking was proposed.Firstly,the cascading texture structure was used to improve the simple voxel structure,realizing fast and efficient storage of scene illumination information filtered anisotropically,so as to reduce the memory cost.Then,the direct illumination attenuation was calculated based on normal weighted accumulation in order to alleviate the problem of normal consistency.Finally,the cone filter was improved by the cascading texture structure,which realized the dynamic voxel search and avoided the traversal of the entire storage structure,and the effective calculation of global illumination was achieved.The experimental results show that,the improved algorithm can reduce the memory footprint and improve the rendering speed while maintaining the similar rendering effect to that of the classic voxel cone tracking algorithm.