# glGetClipPlane

return the coefficients of the specified clipping plane

## Signature

glGetClipPlane( GLenum ( plane ) , GLdouble * ( equation ) )-> void
glGetClipPlane( )

## Parameters

VariablesDescription
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_PLANE $\mathit{i}$ where i ranges from 0 to the value of GL_MAX_CLIP_PLANES - 1.
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_PLANE $\mathit{i}$ = GL_CLIP_PLANE0 + $\mathit{i}$ .
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 .