import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

devtools/client/shared/webgl-utils.js

@@ -0,0 +1,55 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+"use strict";
+
+const { Cc, Ci } = require("chrome");
+const Services = require("Services");
+
+const WEBGL_CONTEXT_NAME = "experimental-webgl";
+
+function isWebGLForceEnabled() {
+  return Services.prefs.getBoolPref("webgl.force-enabled");
+}
+
+function isWebGLSupportedByGFX() {
+  let supported = false;
+
+  try {
+    let gfxInfo = Cc["@mozilla.org/gfx/info;1"].getService(Ci.nsIGfxInfo);
+    let angle = gfxInfo.FEATURE_WEBGL_ANGLE;
+    let opengl = gfxInfo.FEATURE_WEBGL_OPENGL;
+
+    // if either the Angle or OpenGL renderers are available, WebGL should work
+    supported = gfxInfo.getFeatureStatus(angle) === gfxInfo.FEATURE_STATUS_OK ||
+                gfxInfo.getFeatureStatus(opengl) === gfxInfo.FEATURE_STATUS_OK;
+  } catch (e) {
+    return false;
+  }
+  return supported;
+}
+
+function create3DContext(canvas) {
+  // try to get a valid context from an existing canvas
+  let context = null;
+  try {
+    context = canvas.getContext(WEBGL_CONTEXT_NAME, aFlags);
+  } catch (e) {
+    return null;
+  }
+  return context;
+}
+
+function createCanvas(doc) {
+  return doc.createElementNS("http://www.w3.org/1999/xhtml", "canvas");
+}
+
+function isWebGLSupported(doc) {
+  let supported =
+    !isWebGLForceEnabled() &&
+     isWebGLSupportedByGFX() &&
+     create3DContext(createCanvas(doc));
+
+  return supported;
+}
+exports.isWebGLSupported = isWebGLSupported;