使用光子映射渲染参与介质

光子映射是近年发展起来的一种新的全局光照算法。本文依据光子映射对实体物体的渲染，将其扩展到对包含参与介质的场景的渲染，为此提出了一个两路的渲染算法。在第一路中，光子从光源发射，并使用光子追踪来构造体光子图；第二路从视点出发向场景中发射光线，使用光线追踪来进行渲染，其中，根据构造好的光子图，用光线步进进行
行递归的辐射估计，得出最终光强。

Rendering Participating Media Using Photon Mapping

Photon mapping is a new global illumination algorithm developed in recent years.This article presents a two-pass algorithm to render the scene including participating media,and this algorithm is an expansion of the rendering to solid objects with photon mapping.In the first pass,photons are emitted from a light source.We use photon tracing to trace each photon and to construct a volume photon map.In the second pass,rays are emitted from a sight point.We use ray tracing to trace each ray and use ray marching to perform recursive radiance estimation with the constructed volume photon map and get the final intensity.