GLCLIPPLANE(3G) | GLCLIPPLANE(3G) |
glClipPlane specifies a half-space using a four-component plane equation. When glClipPlane is called, equation is transformed by the inverse of the modelview matrix and stored in the resulting eye coordinates. Subsequent changes to the modelview matrix have no effect on the stored plane-equation components. If the dot product of the eye coordinates of a vertex with the stored plane equation components is positive or zero, the vertex is in with respect to that clipping plane. Otherwise, it is out.
To enable and disable clipping planes, call glEnable and glDisable with the argument GL_CLIP_PLANEi, where i is the plane number.
All clipping planes are initially defined as (0, 0, 0, 0) in eye coordinates and are disabled.
GL_INVALID_OPERATION is generated if glClipPlane is executed between the execution of glBegin and the corresponding execution of glEnd.