Optimizing rendering is one of the greatest challenges faced by game developers. Most game engines make use of hardware rendering which uses technology specifically built for rendering. Before such hardware existed, game developers had to rely on the CPU to render their games. This is known as software rendering. Software rendering is not commonly used nowadays but has been seen in cases such as a backup for when the end users machine does not support the hardware based renderer of the application. Since the CPU is not purposely built for rendering, unlike the GPU, the developer has to perform optimizations to make the renderer more efficient in terms of speed. In this thesis, we present an approach which is a subset of parallel programming called Single Instruction, Multiple Data. This technique operates on vector based registers which means operations can be performed on multiple pieces of data at once. This is applied to an already built game engine in order to optimize its rendering. The results show a speed-up of 90.5% and a framerate increase from 30 frames per second to 133 frames per second within the rendering routine.