Clip coordinates

The clip coordinate system is a homogeneous coordinate system in the graphics pipeline. In OpenGL, clip coordinates are positioned in the pipeline just after eye or camera coordinates and just before normalized device coordinates.

Objects are transformed via a projection transformation into clip coordinates, at which point it may be efficiently determined on an object-by-object basis which portions of the objects will be visible to the user. All coordinates may then be divided by the w component (the fourth component in homogeneous coordinates) in what is called the perspective division. This transformation puts the objects into normalized device coordinates.

Clipping algorithms

• Newman–Sproull
• Cyrus–Beck
• Sutherland–Hodgman clipping algorithm