A Comparison between GPU-based Volume Ray Casting Implementations: Fragment Shader, Compute Shader, OpenCL, and CUDA

Volume rendering is an important area of study in computer graphics, due to its application in areas such as medicine, physic simulations, oil and gas industries, and others. The main used method nowadays for volume rendering is ray casting. Nevertheless, there are a variety of parallel APIs that can be used to implement it. Thus, it is important to evaluate the performance of ray casting in diferent parallel APIs to help programmers in selecting one of them. In this paper, we present a performance comparison using OpenGL® with fragment shader, OpenGL® with compute shader, OpenCL, and CUDA.