Shaders are programs that run on the graphics processor and replace the formerly fixed OpenGL pipeline.

Shaders are programs that run on the graphics processor and replace the formerly fixed OpenGL pipeline.

Coin-2.5 added support for shaders. Shaders replace the fixed function vertex and fragment processing in OpenGL by letting the user define the processing that takes place at key points in the OpenGL pipeline. Vertex shaders handle the operations that occur on each vertex, while fragment shaders handle the operations that occur on each pixel. The SoShaderProgram node in Coin provides a convenient way of specifying the code for vertex and fragment shaders.

Coin-3.0 expanded upon the shader support by adding support for OpenGL Vertex Attributes. When using shaders, programmers are no longer limited to the set of attributes that OpenGL defines (glColor, glNormal, glTexCoord etc.) You can now define your own per-vertex data and pass them to the shaders using the SoVertexAttribute node.