allow scale to be two dimensional

add getScaleArray() method

test two dimension scale icons
test two dimension scale text

add example of icon and label scaling
use smaller icon and larger interval
test two dimensional scale icons
test two dimensional scale icons

src/ol/style/Image.js

@@ -2,13 +2,14 @@
  * @module ol/style/Image
  */
 import {abstract} from '../util.js';
+import {toSize} from '../size.js';
 
 /**
  * @typedef {Object} Options
  * @property {number} opacity
  * @property {boolean} rotateWithView
  * @property {number} rotation
- * @property {number} scale
+ * @property {number|import("../size.js").Size} scale
  * @property {Array<number>} displacement
  */
 
@@ -45,10 +46,16 @@ class ImageStyle {
 
     /**
      * @private
-     * @type {number}
+     * @type {number|import("../size.js").Size}
      */
     this.scale_ = options.scale;
 
+    /**
+     * @private
+     * @type {import("../size.js").Size}
+     */
+    this.scaleArray_ = toSize(options.scale);
+
     /**
      * @private
      * @type {Array<number>}
@@ -62,9 +69,10 @@ class ImageStyle {
    * @api
    */
   clone() {
+    const scale = this.getScale();
     return new ImageStyle({
       opacity: this.getOpacity(),
-      scale: this.getScale(),
+      scale: Array.isArray(scale) ? scale.slice() : scale,
       rotation: this.getRotation(),
       rotateWithView: this.getRotateWithView(),
       displacement: this.getDisplacement().slice(),
@@ -100,13 +108,21 @@ class ImageStyle {
 
   /**
    * Get the symbolizer scale.
-   * @return {number} Scale.
+   * @return {number|import("../size.js").Size} Scale.
    * @api
    */
   getScale() {
     return this.scale_;
   }
 
+  /**
+   * Get the symbolizer scale array.
+   * @return {import("../size.js").Size} Scale array.
+   */
+  getScaleArray() {
+    return this.scaleArray_;
+  }
+
   /**
    * Get the displacement of the shape
    * @return {Array<number>} Shape's center displacement
@@ -219,11 +235,12 @@ class ImageStyle {
   /**
    * Set the scale.
    *
-   * @param {number} scale Scale.
+   * @param {number|import("../size.js").Size} scale Scale.
    * @api
    */
   setScale(scale) {
     this.scale_ = scale;
+    this.scaleArray_ = toSize(scale);
   }
 
   /**