Accelerating Hash Grid and Screen-Space Photon Mapping in 3D Interactive Applications with OpenCL

Abstract

Achieving interactive and realistic rendering is only possible with a combination of rendering algorithms, rendering pipelines, multi-core hardware, and parallelization APIs. This project explores and implements two photon mapping pipelines based on the work of Mara et. al [5] and Singh et. al [7] to achieve interactive rendering performance for a set of simple scenes using OpenCL and C++ to work with a GPU. In particular, both a 3D hash grid and a screen-space tiling algorithm are parallelized to accelerate photon lookup in order to compute direct and indirect lighting on visible surfaces in a scene. By using OpenCL with photon mapping interactive renderings of scenes were produced and updated live as a user moved a virtual camera. This work with OpenCL paved the way for developing a raytracing pipeline in OpenGL and for future work on the latest research in realtime realistic rendering