Ray casting is a rendering technique used in computer graphics and computational geometry. It is capable of creating a three-dimensional perspective in a two-dimensional map. Developed by scientists at the Mathematical Applications Group in the 1960. it is considered one of the most basic graphics-rendering algorithms. Ray casting makes use of the same geometric algorithm as ray tracing. Advantage: Ray casting is fast, as only a single computation is needed for every vertical line of the screen. Compared to ray tracing, ray casting is faster, as it is limited by one or more geometric constraints. his is one of the reasons why ray casting was the most popular rendering tool in early 3-D video games.