JGE/src/hge/hgevector.cpp

@@ -0,0 +1,69 @@
+/*
+** Haaf's Game Engine 1.7
+** Copyright (C) 2003-2007, Relish Games
+** hge.relishgames.com
+**
+** hgeVector helper class implementation
+*/
+
+
+#include "../../include/hge/hgevector.h"
+
+float InvSqrt(float x)
+{
+		union
+        {
+          int intPart;
+          float floatPart;
+        } convertor;
+
+        convertor.floatPart = x;
+        convertor.intPart = 0x5f3759df - (convertor.intPart >> 1);
+        return convertor.floatPart*(1.5f - 0.4999f*x*convertor.floatPart*convertor.floatPart);
+}
+
+/*
+hgeVector *hgeVector::Normalize()
+{
+	float lenRcp;
+
+	lenRcp=sqrtf(Dot(this));
+
+	if(lenRcp)
+	{
+		lenRcp=1.0f/lenRcp;
+
+		x*=lenRcp;
+		y*=lenRcp;
+	}
+
+	return this;
+}
+*/
+
+float hgeVector::Angle(const hgeVector *v) const
+{
+	if(v)
+	{
+		hgeVector s=*this, t=*v;
+
+		s.Normalize(); t.Normalize();
+		return acosf(s.Dot(&t));
+	}
+	else return atan2f(y, x);
+}
+
+hgeVector *hgeVector::Rotate(float a)
+{
+	hgeVector v;
+
+	v.x=x*cosf(a) - y*sinf(a);
+	v.y=x*sinf(a) + y*cosf(a);
+
+	x=v.x; y=v.y;
+
+	return this;
+}
+
+
+