func LineWidth(width float32) {
	syscall.Syscall(gpLineWidth, 1, uintptr(math.Float32bits(width)), 0, 0)
}
func LineWidth(width float32) {
	syscall.Syscall(gpLineWidth, 1, uintptr(math.Float32bits(width)), 0, 0)
}
func LineWidth ( width float32 ) { syscall . Syscall ( gpLineWidth , 1 , uintptr ( math . Float32bits ( width ) ) , 0 , 0 ) }
// specify the width of rasterized lines
specify the width of rasterized lines