2 files changed, 11 insertions, 0 deletions
diff --git a/src/math/Vector.h b/src/math/Vector.h
index 7ee01149..082b296f 100644
--- a/src/math/Vector.h
+++ b/src/math/Vector.h
@@ -115,6 +115,14 @@ Distance(const CVector &v1, const CVector &v2)
 	return (v2 - v1).Magnitude();
 }
 
+inline float
+Distance2D(const CVector &v1, const CVector &v2)
+{
+	float x = v2.x - v1.x;
+	float y = v2.y - v1.y;
+	return Sqrt(x*x + y*y);
+}
+
 class CMatrix;
 
 CVector Multiply3x3(const CMatrix &mat, const CVector &vec);
diff --git a/src/math/Vector2D.h b/src/math/Vector2D.h
index 2c4e57b5..deabd0b1 100644
--- a/src/math/Vector2D.h
+++ b/src/math/Vector2D.h
@@ -53,6 +53,9 @@ public:
 	CVector2D operator/(float t) const {
 		return CVector2D(x/t, y/t);
 	}
+	CVector2D operator-() const {
+		return CVector2D(-x, -y);
+	}
 };
 
 inline float