func DepthRangef(n float32, f float32) {
	syscall.Syscall(gpDepthRangef, 2, uintptr(math.Float32bits(n)), uintptr(math.Float32bits(f)), 0)
}
func DepthRangef(n float32, f float32) {
	syscall.Syscall(gpDepthRangef, 2, uintptr(math.Float32bits(n)), uintptr(math.Float32bits(f)), 0)
}
func DepthRangef ( n float32 , f float32 ) { syscall . Syscall ( gpDepthRangef , 2 , uintptr ( math . Float32bits ( n ) ) , uintptr ( math . Float32bits ( f ) ) , 0 ) }
// specify mapping of depth values from normalized device coordinates to window coordinates
specify mapping of depth values from normalized device coordinates to window coordinates