Abstract
The developments of computing hardware architectures are heading in a direction toward parallel computing. Whereas better and faster CPUs used to mean higher clock rates, better and faster CPUs now means more cores per chip. Additionally, GPUs are emerging as powerful parallel processing devices when computing particular types of problems. Computers today have a tremendous amount of varied parallel processing power. Utilizing these different devices typically means wrestling with varied architecture, vendor, or platform specific programming models and code. OpenCL is an open-standard designed to provide developers with a standard interface for programming varied (heterogeneous) parallel devices. This standard allows single source codes to define algorithms to solve vectorized problems on various parallel devices on the same machine. These programs are also portable. This project explores OpenCL to implement a cross-platform, parallel solution to a vectorized problem. The domain of the problem is ray-tracing. Ray-tracing is a computer graphics rendering algorithm that determines how to visualize a scene. A significant number of calculations are performed to colorize each pixel based on the data of the 3D objects in the scene. Though heavy, the calculations for each pixel can be made completely independently from the calculations of any of the other pixels. The project has a GUI implemented in C++. The project has a ray-tracing engine implemented in C++. The ray-traced rendering routines come in four implementations: 1) written recursively in C++, executed on the CPU cores; 2) written iteratively in C++, executed on the CPU cores; 3) written iteratively in OpenCL C, executed in parallel on the CPU cores; 4) written iteratively in OpenCL C, executed in parallel on the GPU cores. The GUI reports the running time to perform the ray-tracing calculations to visualize the scene to the frame buffer for each ray-tracing implementation.