为了加速采用光子映射技术进行实时真实感散射效果的渲染效率,提出一种基于虚拟小光线束光源的介质单次散射并行绘制算法.首先用平面对介质进行采样得到光子,根据场景中的采样光子来生成小光线束,小光线束中每一点的宽度通过小光线束两端光子的宽度插值得到;然后用与视点光线相交的小光线束来估计视点光线的辐射度;最后根据每条视点光线得到的辐射度来渲染最终的图像.实验结果表明,该算法能够处理多种介质散射效果,且提高了散射效果的渲染效率.
In order to accelerate the real-time rendering efficiency with the photon mapping, a virtual beamlet lights based parallel scattering algorithm is presented in this paper. Firstly, photons in medium are obtained by sampling plane, the beamlet is generated according to the sampling photons in the scene, and the width of each point in the beamlet is gained through interpolation between the both ends photon width. Then, the radiation of the view ray is estimated using the beamlet which intersects the view ray. Lastly, the final image is rendered according to the radiation of each view ray. The experimental results show that proposed algorithm can implement many kinds of scattering effects and improve the rendering efficiency for participating media.