glEdgeFlagPointer is available only if the GL version is 1.1 or greater.The edge flag array is initially disabled and it won't be accessed when
glArrayElement, glDrawElements or glDrawArrays is called.
Execution of glEdgeFlagPointer is not allowed between the execution of glBegin and the corresponding execution of glEnd, but an error may or may not be generated. If no error is generated, the operation is undefined.
glEdgeFlagPointer is typically implemented on the client side.
Edge flag array parameters are client-side state and are therefore not saved or restored by
glPushAttrib and glPopAttrib. Use glPushClientAttrib and
glPopClientAttrib instead.