Merge pull request #4996 from weslord/static-normalize

Add static version of p5.Vector.normalize()
processing · Jan 30, 2021 · 5db68fb · 5db68fb
2 parents f2f8bb1 + 4143134
commit 5db68fb
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Showing 2 changed files with 85 additions and 14 deletions.
diff --git a/src/math/p5.Vector.js b/src/math/p5.Vector.js
@@ -1213,6 +1213,20 @@ p5.Vector.prototype.dist = function dist(v) {
  * // [0.4454354, 0.8908708, 0.089087084]
  * </code>
  * </div>
+ *
+ * <div class="norender">
+ * <code>
+ * // Static method
+ * let v_initial = createVector(10, 20, 2);
+ * // v_initial has components [10.0, 20.0, 2.0]
+ * let v_normalized = p5.Vector.normalize(v_initial);
+ * print(v_normalized);
+ * // returns a new vector with components set to
+ * // [0.4454354, 0.8908708, 0.089087084]
+ * // v_initial remains unchanged
+ * </code>
+ * </div>
+ *
  * <div>
  * <code>
  * function draw() {
@@ -2303,11 +2317,15 @@ p5.Vector.lerp = function lerp(v1, v2, amt, target) {
   return target;
 };
 
+/**
+ * Calculates the magnitude (length) of the vector and returns the result as
+ * a float (this is simply the equation sqrt(x\*x + y\*y + z\*z).)
+ */
 /**
  * @method mag
+ * @static
  * @param {p5.Vector} vecT the vector to return the magnitude of
  * @return {Number}        the magnitude of vecT
- * @static
  */
 p5.Vector.mag = function mag(vecT) {
   const x = vecT.x,
@@ -2317,4 +2335,29 @@ p5.Vector.mag = function mag(vecT) {
   return Math.sqrt(magSq);
 };
 
+/**
+ * Normalize the vector to length 1 (make it a unit vector).
+ */
+/**
+ * @method normalize
+ * @static
+ * @param {p5.Vector} v  the vector to normalize
+ * @param {p5.Vector} [target] the vector to receive the result (Optional)
+ * @return {p5.Vector}   v normalized to a length of 1
+ */
+p5.Vector.normalize = function normalize(v, target) {
+  if (arguments.length < 2) {
+    target = v.copy();
+  } else {
+    if (!(target instanceof p5.Vector)) {
+      p5._friendlyError(
+        'The target parameter should be of type p5.Vector',
+        'p5.Vector.normalize'
+      );
+    }
+    target.set(v);
+  }
+  return target.normalize();
+};
+
 export default p5.Vector;
diff --git a/test/unit/math/p5.Vector.js b/test/unit/math/p5.Vector.js
@@ -868,18 +868,16 @@ suite('p5.Vector', function() {
   });
 
   suite('normalize', function() {
-    setup(function() {
-      v.x = 1;
-      v.y = 1;
-      v.z = 1;
-    });
+    suite('v.normalize()', function() {
+      setup(function() {
+        v = myp5.createVector(1, 1, 1);
+      });
 
-    test('should return the same object', function() {
-      expect(v.normalize()).to.eql(v);
-    });
+      test('should return the same object', function() {
+        expect(v.normalize()).to.eql(v);
+      });
 
-    suite('with unit vector', function() {
-      test('should not change the vector', function() {
+      test('unit vector should not change values', function() {
         v.x = 1;
         v.y = 0;
         v.z = 0;
@@ -888,10 +886,8 @@ suite('p5.Vector', function() {
         expect(v.y).to.eql(0);
         expect(v.z).to.eql(0);
       });
-    });
 
-    suite('with 2,2,1', function() {
-      test('should normalize to 0.66,0.66,0.33', function() {
+      test('2,2,1 should normalize to ~0.66,0.66,0.33', function() {
         v.x = 2;
         v.y = 2;
         v.z = 1;
@@ -901,6 +897,38 @@ suite('p5.Vector', function() {
         expect(v.z).to.be.closeTo(0.3333, 0.01);
       });
     });
+
+    suite('p5.Vector.normalize(v)', function() {
+      var res;
+      setup(function() {
+        v = myp5.createVector(1, 0, 0);
+        res = p5.Vector.normalize(v);
+      });
+
+      test('should not be undefined', function() {
+        expect(res).to.not.eql(undefined);
+      });
+
+      test('should not return same object v', function() {
+        expect(res).to.not.equal(v);
+      });
+
+      test('unit vector 1,0,0 should normalize to 1,0,0', function() {
+        expect(res.x).to.eql(1);
+        expect(res.y).to.eql(0);
+        expect(res.z).to.eql(0);
+      });
+
+      test('2,2,1 should normalize to ~0.66,0.66,0.33', function() {
+        v.x = 2;
+        v.y = 2;
+        v.z = 1;
+        res = p5.Vector.normalize(v);
+        expect(res.x).to.be.closeTo(0.6666, 0.01);
+        expect(res.y).to.be.closeTo(0.6666, 0.01);
+        expect(res.z).to.be.closeTo(0.3333, 0.01);
+      });
+    });
   });
 
   suite('limit', function() {