From b5378deb4570360f9821415eb770613f53b0c16b Mon Sep 17 00:00:00 2001
From: Tim Schaub <tim.schaub@gmail.com>
Date: Wed, 14 Nov 2018 21:42:10 +0100
Subject: [PATCH] Create context in the canvas layer base class

---
 src/ol/renderer/canvas/ImageLayer.js  |  9 ---------
 src/ol/renderer/canvas/Layer.js       | 11 +++++++++++
 src/ol/renderer/canvas/TileLayer.js   |  9 ---------
 src/ol/renderer/canvas/VectorLayer.js | 10 ----------
 4 files changed, 11 insertions(+), 28 deletions(-)

diff --git a/src/ol/renderer/canvas/ImageLayer.js b/src/ol/renderer/canvas/ImageLayer.js
index 6f6fe12e4b..39fb886b7a 100644
--- a/src/ol/renderer/canvas/ImageLayer.js
+++ b/src/ol/renderer/canvas/ImageLayer.js
@@ -22,15 +22,6 @@ class CanvasImageLayerRenderer extends CanvasLayerRenderer {
   constructor(imageLayer) {
     super(imageLayer);
 
-    /**
-     * @protected
-     * @type {CanvasRenderingContext2D}
-     */
-    this.context = createCanvasContext2D();
-
-    const canvas = this.context.canvas;
-    canvas.style.position = 'absolute';
-
     /**
      * @protected
      * @type {import("../../transform.js").Transform}
diff --git a/src/ol/renderer/canvas/Layer.js b/src/ol/renderer/canvas/Layer.js
index d1b4bd01bd..3dbb80ade1 100644
--- a/src/ol/renderer/canvas/Layer.js
+++ b/src/ol/renderer/canvas/Layer.js
@@ -2,6 +2,7 @@
  * @module ol/renderer/canvas/Layer
  */
 import {getBottomLeft, getBottomRight, getTopLeft, getTopRight} from '../../extent.js';
+import {createCanvasContext2D} from '../../dom.js';
 import {TRUE} from '../../functions.js';
 import RenderEvent from '../../render/Event.js';
 import RenderEventType from '../../render/EventType.js';
@@ -34,6 +35,16 @@ class CanvasLayerRenderer extends LayerRenderer {
      */
     this.transform_ = createTransform();
 
+    /**
+     * @protected
+     * @type {CanvasRenderingContext2D}
+     */
+    this.context = createCanvasContext2D();
+
+    const canvas = this.context.canvas;
+    canvas.style.position = 'absolute';
+    canvas.className = this.getLayer().getClassName();
+
   }
 
   /**
diff --git a/src/ol/renderer/canvas/TileLayer.js b/src/ol/renderer/canvas/TileLayer.js
index bb03bb1476..9eb91e7ddb 100644
--- a/src/ol/renderer/canvas/TileLayer.js
+++ b/src/ol/renderer/canvas/TileLayer.js
@@ -22,15 +22,6 @@ class CanvasTileLayerRenderer extends CanvasLayerRenderer {
   constructor(tileLayer) {
     super(tileLayer);
 
-    /**
-     * @protected
-     * @type {CanvasRenderingContext2D}
-     */
-    this.context = createCanvasContext2D();
-
-    const canvas = this.context.canvas;
-    canvas.style.position = 'absolute';
-
     /**
      * @protected
      * @type {import("../../transform.js").Transform}
diff --git a/src/ol/renderer/canvas/VectorLayer.js b/src/ol/renderer/canvas/VectorLayer.js
index ea80b70909..d611d07aa6 100644
--- a/src/ol/renderer/canvas/VectorLayer.js
+++ b/src/ol/renderer/canvas/VectorLayer.js
@@ -3,7 +3,6 @@
  */
 import {getUid} from '../../util.js';
 import ViewHint from '../../ViewHint.js';
-import {createCanvasContext2D} from '../../dom.js';
 import {listen, unlisten} from '../../events.js';
 import EventType from '../../events/EventType.js';
 import rbush from 'rbush';
@@ -77,15 +76,6 @@ class CanvasVectorLayerRenderer extends CanvasLayerRenderer {
      */
     this.replayGroupChanged = true;
 
-    /**
-     * @type {CanvasRenderingContext2D}
-     */
-    this.context = createCanvasContext2D();
-
-    const canvas = this.context.canvas;
-    canvas.style.position = 'absolute';
-    canvas.className = this.getLayer().getClassName();
-
     listen(labelCache, EventType.CLEAR, this.handleFontsChanged_, this);
   }