GLCLIPPLANE
Section: Misc. Reference Manual Pages (3G)
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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 between 0 and GL_MAX_CLIP_PLANES$^^1$,
are accepted.
 equation

Specifies the address of an array of four doubleprecision floatingpoint values.
These values are interpreted as a plane equation.
DESCRIPTION
Geometry is always clipped against the boundaries of a sixplane 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 additional clipping planes, call
glGetIntegerv with argument GL_MAX_CLIP_PLANES. All
implementations support at least six such clipping planes.
Because the resulting clipping region is the intersection
of the defined halfspaces,
it is always convex.
glClipPlane specifies a halfspace using a fourcomponent 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 planeequation 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.
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(3G)
Index
 NAME

 C SPECIFICATION

 PARAMETERS

 DESCRIPTION

 NOTES

 ERRORS

 ASSOCIATED GETS

 SEE ALSO

linux.jgfs.net manual pages