# glgetclipplane(3g) [osx man page]

GLGETCLIPPLANE(3G) GLGETCLIPPLANE(3G)NAME

glGetClipPlane - return the coefficients of the specified clipping planeC SPECIFICATION

void glGetClipPlane( GLenum plane, GLdouble *equation )PARAMETERS

plane Specifies a clipping plane. The number of clipping planes depends on the implementation, but at least six clipping planes are supported. They are identified by symbolic names of the form GL_CLIP_PLANEi where 0 <= i < GL_MAX_CLIP_PLANES. equation Returns four double-precision values that are the coefficients of the plane equation of plane in eye coordinates. The initial value is (0, 0, 0, 0).DESCRIPTION

glGetClipPlane returns in equation the four coefficients of the plane equation for plane.NOTES

It is always the case that GL_CLIP_PLANEi = GL_CLIP_PLANE0 + i. If an error is generated, no change is made to the contents of equation.ERRORS

GL_INVALID_ENUM is generated if plane is not an accepted value. GL_INVALID_OPERATION is generated if glGetClipPlane is executed between the execution of glBegin and the corresponding execution of glEnd.SEE ALSO

glClipPlane GLGETCLIPPLANE(3G)

## Check Out this Related Man Page

GLCLIPPLANE(3G) GLCLIPPLANE(3G)NAME

glClipPlane - specify a plane against which all geometry is clippedC SPECIFICATION

void glClipPlane( GLenum plane, 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 between 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 equa- tion.DESCRIPTION

Geometry is always clipped against the boundaries of a six-plane frustum in x, y, and z. glClipPlane allows the specification of addi- tional planes, not necessarily perpendicular to the x, y, or z axis, against which all geometry is clipped. To determine the maximum num- ber of additional 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 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.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_PLANEiSEE ALSO

glEnable GLCLIPPLANE(3G)