diff --git a/binaries/data/mods/public/globalscripts/vector.js b/binaries/data/mods/public/globalscripts/vector.js
index 3c451658d4..f792830a45 100644
--- a/binaries/data/mods/public/globalscripts/vector.js
+++ b/binaries/data/mods/public/globalscripts/vector.js
@@ -16,6 +16,11 @@ function Vector2D(x, y)
 		this.set(0, 0);
 }
 
+Vector2D.prototype.clone = function()
+{
+	return new Vector2D(this.x, this.y);
+};
+
 // Mutating 2D functions
 //
 // These functions modify the current object,
@@ -70,8 +75,15 @@ Vector2D.prototype.normalize = function()
  */
 Vector2D.prototype.rotate = function(a)
 {
-	this.x = this.x * Math.cos(a) + this.y * Math.sin(a);
-	this.y = this.y * Math.cos(a) - this.x * Math.sin(a);
+	let sin = Math.sin(a);
+	let cos = Math.cos(a);
+
+	let x = this.x * cos + this.y * sin;
+	let y = this.y * cos - this.x * sin;
+
+	this.x = x;
+	this.y = y;
+
 	return this;
 };
 
@@ -179,6 +191,11 @@ function Vector3D(x, y, z)
 		this.set(0, 0, 0);
 }
 
+Vector3D.prototype.clone = function()
+{
+	return new Vector3D(this.x, this.y, this.z);
+};
+
 // Mutating 3D functions
 //
 // These functions modify the current object,
diff --git a/binaries/data/mods/public/simulation/components/tests/test_Vector.js b/binaries/data/mods/public/simulation/components/tests/test_Vector.js
index e89dbffe4b..c70e35bd55 100644
--- a/binaries/data/mods/public/simulation/components/tests/test_Vector.js
+++ b/binaries/data/mods/public/simulation/components/tests/test_Vector.js
@@ -35,6 +35,43 @@ var brokenVector = {
 	TS_ASSERT_EQUALS(v4.x, -2);
 	TS_ASSERT_EQUALS(v4.y, 5);
 
+	// Result of rotating (1, 0)
+	let unitCircle = [
+		{
+			"angle": Math.PI / 2,
+			"x": 0,
+			"y": 1
+		},
+		{
+			"angle": Math.PI / 3,
+			"x": 1/2,
+			"y": Math.sqrt(3) / 2
+		},
+		{
+			"angle": Math.PI / 4,
+			"x": Math.sqrt(2) / 2,
+			"y": Math.sqrt(2) / 2
+		},
+		{
+			"angle": Math.PI / 6,
+			"x": Math.sqrt(3) / 2,
+			"y": 1/2
+		}
+	];
+
+	let epsilon = 0.00000001;
+
+	for (let expectedVector of unitCircle)
+	{
+		let computedVector = new Vector2D(1, 0).rotate(-expectedVector.angle);
+		for (let s of ["x", "y"])
+			if (Math.abs(expectedVector[s] - computedVector[s]) > epsilon)
+			{
+				TS_FAIL("Expected " + uneval(expectedVector) + " got " + uneval(computedVector));
+				break;
+			}
+	}
+
 	TS_ASSERT_EQUALS(new Vector2D(2, 3).dot(new Vector2D(4, 5)), 23);
 	TS_ASSERT_EQUALS(new Vector2D(3, 5).cross(new Vector2D(-4, -1/3)), 19);
 	TS_ASSERT_EQUALS(new Vector2D(20, 21).length(), 29);
@@ -44,6 +81,11 @@ var brokenVector = {
 	TS_ASSERT_EQUALS(v5.compareLength(new Vector2D(500, 800)), -1);
 	TS_ASSERT_EQUALS(v5.compareLength(new Vector2D(10, 20)), 0);
 	TS_ASSERT(isNaN(v5.compareLength(brokenVector)));
+
+	let v6 = v5.clone();
+	TS_ASSERT_EQUALS(v5.x, v6.x);
+	TS_ASSERT_EQUALS(v5.y, v6.y);
+	TS_ASSERT(Math.abs(v5.dot(v6.rotate(Math.PI / 2))) < epsilon);
 }
 
 // Test Vector3D
@@ -59,4 +101,9 @@ var brokenVector = {
 
 	TS_ASSERT_EQUALS(new Vector3D(1, 2, 3).dot(new Vector3D(4, 5, 6)), 32);
 
-}
\ No newline at end of file
+	let v3 = new Vector3D(9, 10, 11);
+	let v4 = v3.clone();
+	TS_ASSERT_EQUALS(v3.x, v4.x);
+	TS_ASSERT_EQUALS(v3.y, v4.y);
+	TS_ASSERT_EQUALS(v3.z, v4.z);
+}