1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/browser/metro/base/content/apzc.js Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,153 @@
1.4 +// -*- Mode: js2; tab-width: 2; indent-tabs-mode: nil; js2-basic-offset: 2; js2-skip-preprocessor-directives: t; -*-
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +let Cc = Components.classes;
1.10 +let Ci = Components.interfaces;
1.11 +let Cu = Components.utils;
1.12 +let Cr = Components.results;
1.13 +
1.14 +/**
1.15 + * Misc. front end utilities for apzc management.
1.16 + * the pref: layers.async-pan-zoom.enabled is true.
1.17 + */
1.18 +
1.19 +var APZCObserver = {
1.20 + _debugEvents: false,
1.21 + _enabled: false,
1.22 +
1.23 + get enabled() {
1.24 + return this._enabled;
1.25 + },
1.26 +
1.27 + init: function() {
1.28 + this._enabled = Services.prefs.getBoolPref(kAsyncPanZoomEnabled);
1.29 + if (!this._enabled) {
1.30 + return;
1.31 + }
1.32 +
1.33 + let os = Services.obs;
1.34 + os.addObserver(this, "apzc-transform-begin", false);
1.35 +
1.36 + Elements.tabList.addEventListener("TabSelect", this, true);
1.37 + Elements.browsers.addEventListener("pageshow", this, true);
1.38 + messageManager.addMessageListener("Content:ZoomToRect", this);
1.39 + },
1.40 +
1.41 + shutdown: function shutdown() {
1.42 + if (!this._enabled) {
1.43 + return;
1.44 + }
1.45 +
1.46 + let os = Services.obs;
1.47 + os.removeObserver(this, "apzc-transform-begin");
1.48 +
1.49 + Elements.tabList.removeEventListener("TabSelect", this, true);
1.50 + Elements.browsers.removeEventListener("pageshow", this, true);
1.51 + messageManager.removeMessageListener("Content:ZoomToRect", this);
1.52 + },
1.53 +
1.54 + handleEvent: function APZC_handleEvent(aEvent) {
1.55 + switch (aEvent.type) {
1.56 + case 'TabSelect':
1.57 + this._resetDisplayPort();
1.58 + break;
1.59 +
1.60 + case 'pageshow':
1.61 + if (aEvent.target != Browser.selectedBrowser.contentDocument) {
1.62 + break;
1.63 + }
1.64 + this._resetDisplayPort();
1.65 + break;
1.66 + }
1.67 + },
1.68 +
1.69 + observe: function ao_observe(aSubject, aTopic, aData) {
1.70 + if (aTopic == "apzc-transform-begin") {
1.71 + // When we're panning, hide the main scrollbars by setting imprecise
1.72 + // input (which sets a property on the browser which hides the scrollbar
1.73 + // via CSS). This reduces jittering from left to right. We may be able
1.74 + // to get rid of this once we implement axis locking in /gfx APZC.
1.75 + if (InputSourceHelper.isPrecise) {
1.76 + InputSourceHelper._imprecise();
1.77 + }
1.78 + }
1.79 + },
1.80 +
1.81 + receiveMessage: function(aMessage) {
1.82 + let json = aMessage.json;
1.83 + let browser = aMessage.target;
1.84 + switch (aMessage.name) {
1.85 + case "Content:ZoomToRect": {
1.86 + let { presShellId, viewId } = json;
1.87 + let rect = Rect.fromRect(json.rect);
1.88 + if (this.isRectZoomedIn(rect, browser.contentViewportBounds)) {
1.89 + // If we're already zoomed in, zoom out instead.
1.90 + rect = new Rect(0,0,0,0);
1.91 + }
1.92 + let data = [rect.x, rect.y, rect.width, rect.height, presShellId, viewId].join(",");
1.93 + Services.obs.notifyObservers(null, "apzc-zoom-to-rect", data);
1.94 + }
1.95 + }
1.96 + },
1.97 +
1.98 + /**
1.99 + * Check to see if the area of the rect visible in the viewport is
1.100 + * approximately the max area of the rect we can show.
1.101 + * Based on code from BrowserElementPanning.js
1.102 + */
1.103 + isRectZoomedIn: function (aRect, aViewport) {
1.104 + let overlap = aViewport.intersect(aRect);
1.105 + let overlapArea = overlap.width * overlap.height;
1.106 + let availHeight = Math.min(aRect.width * aViewport.height / aViewport.width, aRect.height);
1.107 + let showing = overlapArea / (aRect.width * availHeight);
1.108 + let ratioW = (aRect.width / aViewport.width);
1.109 + let ratioH = (aRect.height / aViewport.height);
1.110 +
1.111 + return (showing > 0.9 && (ratioW > 0.9 || ratioH > 0.9));
1.112 + },
1.113 +
1.114 + _resetDisplayPort: function () {
1.115 + // Start off with something reasonable. The apzc will handle these
1.116 + // calculations once scrolling starts.
1.117 + let doc = Browser.selectedBrowser.contentDocument.documentElement;
1.118 + // While running tests, sometimes this can be null. If we don't have a
1.119 + // root document, there's no point in setting a scrollable display port.
1.120 + if (!doc) {
1.121 + return;
1.122 + }
1.123 + let win = Browser.selectedBrowser.contentWindow;
1.124 + let factor = 0.2;
1.125 + let portX = 0;
1.126 + let portY = 0;
1.127 + let portWidth = ContentAreaObserver.width;
1.128 + let portHeight = ContentAreaObserver.height;
1.129 +
1.130 + if (portWidth < doc.scrollWidth) {
1.131 + portWidth += ContentAreaObserver.width * factor;
1.132 + if (portWidth > doc.scrollWidth) {
1.133 + portWidth = doc.scrollWidth;
1.134 + }
1.135 + }
1.136 + if (portHeight < doc.scrollHeight) {
1.137 + portHeight += ContentAreaObserver.height * factor;
1.138 + if (portHeight > doc.scrollHeight) {
1.139 + portHeight = doc.scrollHeight;
1.140 + }
1.141 + }
1.142 + if (win.scrollX > 0) {
1.143 + portX -= ContentAreaObserver.width * factor;
1.144 + }
1.145 + if (win.scrollY > 0) {
1.146 + portY -= ContentAreaObserver.height * factor;
1.147 + }
1.148 + let cwu = Browser.selectedBrowser.contentWindow
1.149 + .QueryInterface(Ci.nsIInterfaceRequestor)
1.150 + .getInterface(Ci.nsIDOMWindowUtils);
1.151 + cwu.setDisplayPortForElement(portX, portY,
1.152 + portWidth, portHeight,
1.153 + Browser.selectedBrowser.contentDocument.documentElement,
1.154 + 0);
1.155 + }
1.156 +};
