glClearDepth - specify the clear value for the depth buffer
void glClearDepth( GLclampd depth )
depth Specifies the depth value used when the depth buffer is cleared.
glClearDepth specifies the depth value used by glClear to clear the depth buffer. Values specified by glClearDepth are clamped to the range [0,1].
GL_INVALID_OPERATION is generated if glClearDepth is executed between the execution of glBegin and the corresponding execution of glEnd.
glGet with argument GL_DEPTH_CLEAR_VALUE
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Fri Dec 6 11:18:03 EST 1996
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