Function glu_sys::glu::gluUnProject

pub unsafe extern "C" fn gluUnProject(
    winX: GLdouble, 
    winY: GLdouble, 
    winZ: GLdouble, 
    model: *const GLdouble, 
    proj: *const GLdouble, 
    view: *const GLint, 
    objX: *mut GLdouble, 
    objY: *mut GLdouble, 
    objZ: *mut GLdouble
) -> GLint