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