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GLCLIPPLANE()							 GLCLIPPLANE()

NAME
       glClipPlane - specify a plane against which all geometry	is clipped

C SPECIFICATION
       void glClipPlane( GLenum	plane,
			 const GLdouble	*equation )

       delim $$

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 frus-
       tum 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  ad-
       ditional	   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
       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	 coor-
       dinates and are disabled.

NOTES
       It is always the	case that GL_CLIP_PLANE$i$ = 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

								 GLCLIPPLANE()

NAME | C SPECIFICATION | PARAMETERS | DESCRIPTION | NOTES | ERRORS | ASSOCIATED GETS | SEE ALSO

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