Merge pull request #1738 from DonKarlssonSan/master

Fixing Vector.rotate() #1728

Author: lmccart

src/math/p5.Vector.js

@@ -613,12 +613,12 @@ p5.Vector.prototype.heading = function () {
  * </div>
  */
 p5.Vector.prototype.rotate = function (a) {
+  var newHeading = this.heading() + a;
   if (this.p5) {
     if (this.p5._angleMode === constants.DEGREES) {
-      a = polarGeometry.degreesToRadians(a);
+      newHeading = polarGeometry.degreesToRadians(newHeading);
     }
   }
-  var newHeading = this.heading() + a;
   var mag = this.mag();
   this.x = Math.cos(newHeading) * mag;
   this.y = Math.sin(newHeading) * mag;

test/unit/math/p5.Vector.js

@@ -1,5 +1,7 @@
 
 suite('p5.Vector', function() {
+  var RADIANS = 'radians';
+  var DEGREES = 'degrees';
 
   var myp5 = new p5(function( p ) {
     p.setup = function() {};
@@ -84,8 +86,35 @@ suite('p5.Vector', function() {
       assert.equal(v.z, 0);
     });
   });
-});
 
+  suite('p5.prototype.rotate() RADIANS', function() {
+    setup(function() {
+      myp5.angleMode(RADIANS);
+      v = myp5.createVector(0, 1);
+    });
+
+    test('should have x, y, z rotated to 0, -1, 0 (RADIANS)', function() {
+      v.rotate(Math.PI);
+      assert.closeTo(v.x, 0, 0.001);
+      assert.closeTo(v.y, -1, 0.001);
+      assert.closeTo(v.z, 0, 0.001);
+    });
+  });
+
+  suite('p5.prototype.rotate() DEGREES', function() {
+    setup(function() {
+      myp5.angleMode(DEGREES);
+      v = myp5.createVector(0, 1);
+    });
+
+    test('should have x, y, z rotated to 0, -1, 0 (DEGREES)', function() {
+      v.rotate(180);
+      assert.closeTo(v.x, 0, 0.001);
+      assert.closeTo(v.y, -1, 0.001);
+      assert.closeTo(v.z, 0, 0.001);
+    });
+  });
+});
 
 //  describe('set()', function() {
 //     describe('with p5.Vector', function() {