Preserve the drawing buffer by default for WebGL layers

2021-12-18 11:36:44 -07:00
parent c8cfbfccf8
commit 0cc3bae8fe
8 changed files with 72 additions and 2 deletions
@@ -2,6 +2,8 @@
 * @module ol/webgl
 */

+import {assign} from './obj.js';
+
 /**
 * Constants taken from goog.webgl
 */
@@ -89,10 +91,11 @@ const CONTEXT_IDS = ['experimental-webgl', 'webgl', 'webkit-3d', 'moz-webgl'];
 * @return {WebGLRenderingContext} WebGL rendering context.
 */
 export function getContext(canvas, opt_attributes) {
+  const attributes = assign({preserveDrawingBuffer: true}, opt_attributes);
  const ii = CONTEXT_IDS.length;
  for (let i = 0; i < ii; ++i) {
    try {
-      const context = canvas.getContext(CONTEXT_IDS[i], opt_attributes);
+      const context = canvas.getContext(CONTEXT_IDS[i], attributes);
      if (context) {
        return /** @type {!WebGLRenderingContext} */ (context);
      }