const GLdouble *equation )

PARAMETERS
       plane     Specifies  which clipping plane is being positioned.  Symbolic
                 names of the form GL_CLIP_PLANEi, where i is  an  integer  be‐
                 tween 0 and GL_MAX_CLIP_PLANES−1, are accepted.

       equation  Specifies  the  address  of  an array of four double-precision
                 floating-point values.  These  values  are  interpreted  as  a
                 plane equation.

DESCRIPTION
       Geometry is always clipped against the boundaries of a six-plane frustum
       in x, y, and z.  glClipPlane  allows  the  specification  of  additional
       planes,  not  necessarily  perpendicular to the x, y, or z axis, against
       which all geometry is clipped.  To determine the maximum number of addi‐
       tional    clipping    planes,    call    glGetIntegerv   with   argument
       GL_MAX_CLIP_PLANES. All implementations support at least six such  clip‐
       ping  planes.  Because the resulting clipping region is the intersection
       of the defined half-spaces, it is always convex.

       glClipPlane specifies a half-space using a  four-component  plane  equa‐
       tion.   When  glClipPlane  is called, equation is transformed by the in‐
       verse of the modelview matrix and stored in the  resulting  eye  coordi‐
       nates.  Subsequent changes to the modelview matrix have no effect on the
       stored plane-equation components.  If the dot product of the eye coordi‐
       nates  of a vertex with the stored plane equation components is positive
       or zero, the vertex is in with respect to that clipping  plane.   Other‐
       wise, 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 coordi‐
       nates and are disabled.

NOTES
       It is always the case that GL_CLIP_PLANEi = GL_CLIP_PLANE0+i.

ERRORS
       GL_INVALID_ENUM is generated if plane is not an accepted value.

       GL_INVALID_OPERATION is generated if glClipPlane is executed between the
       execution of glBegin and the corresponding execution of glEnd.

ASSOCIATED GETS
       glGetClipPlane
       glIsEnabled with argument GL_CLIP_PLANEi

SEE ALSO
       glEnable