зеркало из https://github.com/mozilla/gecko-dev.git
56 строки
1.5 KiB
JavaScript
56 строки
1.5 KiB
JavaScript
/* 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;
|