有人在Quake III的源代码里面发现这么一段用来求平方根的代码: /*================SquareRootFloat================*/ float SquareRootFloat(float number) { long i; float x, y; const float f = 1.5F; x = number * 0.5F; y = number; i = * ( long * ) &y; i = 0x5f3759df – ( i >> 1 ); //注意这一行 y = * ( float *
