1 files changed, 50 insertions, 1 deletions
diff --git a/src/math/Vector2D.h b/src/math/Vector2D.h
index c8835ec0..a090155c 100644
--- a/src/math/Vector2D.h
+++ b/src/math/Vector2D.h
@@ -18,7 +18,30 @@ public:
 			x *= invsqrt;
 			y *= invsqrt;
 		}else
-			x = 0.0f;
+			x = 1.0f;
+	}
+	const CVector2D &operator+=(CVector2D const &right) {
+		x += right.x;
+		y += right.y;
+		return *this;
+	}
+
+	const CVector2D &operator-=(CVector2D const &right) {
+		x -= right.x;
+		y -= right.y;
+		return *this;
+	}
+
+	const CVector2D &operator*=(float right) {
+		x *= right;
+		y *= right;
+		return *this;
+	}
+
+	const CVector2D &operator/=(float right) {
+		x /= right;
+		y /= right;
+		return *this;
 	}
 	CVector2D operator-(const CVector2D &rhs) const {
 		return CVector2D(x-rhs.x, y-rhs.y);
@@ -29,6 +52,9 @@ public:
 	CVector2D operator*(float t) const {
 		return CVector2D(x*t, y*t);
 	}
+	CVector2D operator/(float t) const {
+		return CVector2D(x/t, y/t);
+	}
 };
 
 inline float
@@ -42,3 +68,26 @@ CrossProduct2D(const CVector2D &v1, const CVector2D &v2)
 {
 	return v1.x*v2.y - v1.y*v2.x;
 }
+
+inline float
+Distance2D(const CVector2D &v, float x, float y)
+{
+	return Sqrt((v.x-x)*(v.x-x) + (v.y-y)*(v.y-y));
+}
+
+inline float
+DistanceSqr2D(const CVector2D &v, float x, float y)
+{
+	return (v.x-x)*(v.x-x) + (v.y-y)*(v.y-y);
+}
+
+inline void
+NormalizeXY(float &x, float &y)
+{
+	float l  = Sqrt(x*x + y*y);
+	if(l != 0.0f){
+		x /= l;
+		y /= l;
+	}else
+		x = 1.0f;
+}