Function for making a scale transform

src/ol/transform.js

@@ -162,6 +162,16 @@ export function scale(transform, x, y) {
   return multiply(transform, set(tmp_, x, 0, 0, y, 0, 0));
 }
 
+/**
+ * Creates a scale transform.
+ * @param {!Transform} target Transform to overwrite.
+ * @param {number} x Scale factor x.
+ * @param {number} y Scale factor y.
+ * @return {!Transform} The scale transform.
+ */
+export function makeScale(target, x, y) {
+  return set(target, x, 0, 0, y, 0, 0);
+}
 
 /**
  * Applies translation to the given transform.

test/spec/ol/transform.test.js

@@ -5,6 +5,7 @@ import {
   setFromArray,
   translate,
   scale,
+  makeScale,
   rotate,
   multiply,
   compose,
@@ -69,6 +70,20 @@ describe('ol.transform', function() {
     });
   });
 
+  describe('makeScale()', function() {
+    it('creates a scale transform', function() {
+      const target = create();
+      makeScale(target, 2, 3);
+      expect(target).to.eql([2, 0, 0, 3, 0, 0]);
+    });
+
+    it('returns the target', function() {
+      const target = create();
+      const transform = makeScale(target, 2, 3);
+      expect(transform).to.be(target);
+    });
+  });
+
   describe('rotate()', function() {
     it('applies rotation to a transform', function() {
       const transform = create();