Do not lock label cache entries

src/ol/render/canvas/Executor.js

@@ -18,7 +18,6 @@ import {
 } from '../../transform.js';
 import {createCanvasContext2D} from '../../dom.js';
 import {labelCache, defaultTextAlign, measureTextHeight, measureAndCacheTextWidth, measureTextWidths} from '../canvas.js';
-import Disposable from '../../Disposable.js';
 import RBush from 'rbush/rbush.js';
 
 
@@ -52,7 +51,7 @@ const p3 = [];
 const p4 = [];
 
 
-class Executor extends Disposable {
+class Executor {
   /**
    * @param {number} resolution Resolution.
    * @param {number} pixelRatio Pixel ratio.
@@ -60,7 +59,6 @@ class Executor extends Disposable {
    * @param {SerializableInstructions} instructions The serializable instructions
    */
   constructor(resolution, pixelRatio, overlaps, instructions) {
-    super();
 
     /**
      * @protected
@@ -156,15 +154,6 @@ class Executor extends Disposable {
     this.widths_ = {};
   }
 
-  /**
-   * @inheritDoc
-   */
-  disposeInternal() {
-    labelCache.release(this);
-    super.disposeInternal();
-  }
-
-
   /**
    * @param {string} text Text.
    * @param {string} textKey Text style key.

src/ol/render/canvas/ExecutorGroup.js

@@ -10,7 +10,6 @@ import {isEmpty} from '../../obj.js';
 import BuilderType from './BuilderType.js';
 import {create as createTransform, compose as composeTransform} from '../../transform.js';
 import Executor from './Executor.js';
-import Disposable from '../../Disposable.js';
 
 /**
  * @const
@@ -26,7 +25,7 @@ const ORDER = [
 ];
 
 
-class ExecutorGroup extends Disposable {
+class ExecutorGroup {
   /**
    * @param {import("../../extent.js").Extent} maxExtent Max extent for clipping. When a
    * `maxExtent` was set on the Buillder for this executor group, the same `maxExtent`
@@ -40,7 +39,6 @@ class ExecutorGroup extends Disposable {
    * @param {number=} opt_renderBuffer Optional rendering buffer.
    */
   constructor(maxExtent, resolution, pixelRatio, overlaps, allInstructions, opt_renderBuffer) {
-    super();
 
     /**
      * @private
@@ -128,24 +126,6 @@ class ExecutorGroup extends Disposable {
     }
   }
 
-  /**
-   * @inheritDoc
-   */
-  disposeInternal() {
-    for (const z in this.executorsByZIndex_) {
-      const executors = this.executorsByZIndex_[z];
-      for (const key in executors) {
-        executors[key].disposeInternal();
-      }
-    }
-    if (this.hitDetectionContext_) {
-      const canvas = this.hitDetectionContext_.canvas;
-      canvas.width = 0;
-      canvas.height = 0;
-    }
-
-    super.disposeInternal();
-  }
 
   /**
    * @param {Array<BuilderType>} executors Executors.

src/ol/render/canvas/LabelCache.js

@@ -1,4 +1,3 @@
-import {getUid} from '../../util.js';
 import LRUCache from '../../structs/LRUCache.js';
 
 /**
@@ -11,59 +10,11 @@ import LRUCache from '../../structs/LRUCache.js';
  */
 class LabelCache extends LRUCache {
 
-  /**
-   * @inheritDoc
-   */
-  constructor(opt_highWaterMark) {
-    super(opt_highWaterMark);
-    this.consumers = {};
-  }
-
-  clear() {
-    this.consumers = {};
-    super.clear();
-  }
-
-  /**
-   * @override
-   * @param {string} key Label key.
-   * @param {import("./Executor.js").default} consumer Label consumer.
-   * @return {HTMLCanvasElement} Label.
-   */
-  get(key, consumer) {
-    const canvas = super.get(key);
-    const consumerId = getUid(consumer);
-    if (!(consumerId in this.consumers)) {
-      this.consumers[consumerId] = {};
-    }
-    this.consumers[consumerId][key] = true;
-    return canvas;
-  }
-
-  prune() {
-    outer:
+  expireCache() {
     while (this.canExpireCache()) {
-      const key = this.peekLastKey();
-      for (const consumerId in this.consumers) {
-        if (key in this.consumers[consumerId]) {
-          break outer;
-        }
-      }
-      const canvas = this.pop();
-      canvas.width = 0;
-      canvas.height = 0;
-      for (const consumerId in this.consumers) {
-        delete this.consumers[consumerId][key];
-      }
+      this.pop();
     }
   }
-
-  /**
-   * @param {import("./Executor.js").default} consumer Label consumer.
-   */
-  release(consumer) {
-    delete this.consumers[getUid(consumer)];
-  }
 }
 
 export default LabelCache;

src/ol/render/canvas/TextBuilder.js

@@ -131,8 +131,6 @@ class CanvasTextBuilder extends CanvasBuilder {
      * @type {string}
      */
     this.strokeKey_ = '';
-
-    labelCache.prune();
   }
 
   /**
@@ -140,6 +138,7 @@ class CanvasTextBuilder extends CanvasBuilder {
    */
   finish() {
     const instructions = super.finish();
+    labelCache.expireCache();
     instructions.textStates = this.textStates;
     instructions.fillStates = this.fillStates;
     instructions.strokeStates = this.strokeStates;