In the field of computer graphics, a shader is a computer program that is used primarily to calculate rendering effects on graphics hardware with a high degree of flexibility. Shaders are used to program the graphics processing unit (GPU) programmable rendering pipeline, which has mostly superseded the fixed-function pipeline that allowed only common geometry transformation and pixel-shading functions; with shaders, customized effects can be used.
The modern use of “shader” was introduced to the public by Pixar with their “RenderMan Interface Specification, Version 3.0” originally published in May, 1988.
As graphics processing units evolved, major graphics software libraries such as OpenGL and Direct3D began to support shaders. The first shader-capable GPUs only supported pixel shading, but vertex shaders were quickly introduced once developers realized the power of shaders. Geometry shaders were recently introduced with Direct3D 10 and OpenGL 3.2, but are currently supported only by…