mirror of
https://github.com/mozilla/gecko-dev.git
synced 2024-11-01 06:35:42 +00:00
858 lines
28 KiB
JavaScript
858 lines
28 KiB
JavaScript
/* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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/* vim: set ts=2 sw=2 sts=2 et: */
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/* 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 file,
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* You can obtain one at http://mozilla.org/MPL/2.0/. */
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"use strict";
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dump("############################### browserElementPanning.js loaded\n");
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let { classes: Cc, interfaces: Ci, results: Cr, utils: Cu } = Components;
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Cu.import("resource://gre/modules/XPCOMUtils.jsm");
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Cu.import("resource://gre/modules/Services.jsm");
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Cu.import("resource://gre/modules/Geometry.jsm");
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var global = this;
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const ContentPanning = {
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// Are we listening to touch or mouse events?
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watchedEventsType: '',
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// Are mouse events being delivered to this content along with touch
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// events, in violation of spec?
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hybridEvents: false,
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init: function cp_init() {
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var events;
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try {
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content.document.createEvent('TouchEvent');
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events = ['touchstart', 'touchend', 'touchmove'];
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this.watchedEventsType = 'touch';
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#ifdef MOZ_WIDGET_GONK
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// The gonk widget backend does not deliver mouse events per
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// spec. Third-party content isn't exposed to this behavior,
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// but that behavior creates some extra work for us here.
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let appInfo = Cc["@mozilla.org/xre/app-info;1"];
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let isParentProcess =
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!appInfo || appInfo.getService(Ci.nsIXULRuntime)
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.processType == Ci.nsIXULRuntime.PROCESS_TYPE_DEFAULT;
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this.hybridEvents = isParentProcess;
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#endif
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} catch(e) {
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// Touch events aren't supported, so fall back on mouse.
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events = ['mousedown', 'mouseup', 'mousemove'];
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this.watchedEventsType = 'mouse';
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}
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// If we are using an AsyncPanZoomController for the parent frame,
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// it will handle subframe scrolling too. We don't need to listen for
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// these events.
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if (!this._asyncPanZoomForViewportFrame) {
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let els = Cc["@mozilla.org/eventlistenerservice;1"]
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.getService(Ci.nsIEventListenerService);
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events.forEach(function(type) {
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// Using the system group for mouse/touch events to avoid
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// missing events if .stopPropagation() has been called.
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els.addSystemEventListener(global, type,
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this.handleEvent.bind(this),
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/* useCapture = */ false);
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}.bind(this));
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}
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addMessageListener("Viewport:Change", this._recvViewportChange.bind(this));
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addMessageListener("Gesture:DoubleTap", this._recvDoubleTap.bind(this));
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},
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handleEvent: function cp_handleEvent(evt) {
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if (evt.defaultPrevented || evt.multipleActionsPrevented) {
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// clean up panning state even if touchend/mouseup has been preventDefault.
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if(evt.type === 'touchend' || evt.type === 'mouseup') {
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if (this.dragging &&
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(this.watchedEventsType === 'mouse' ||
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this.findPrimaryPointer(evt.changedTouches))) {
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this._finishPanning();
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}
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}
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return;
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}
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switch (evt.type) {
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case 'mousedown':
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case 'touchstart':
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this.onTouchStart(evt);
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break;
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case 'mousemove':
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case 'touchmove':
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this.onTouchMove(evt);
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break;
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case 'mouseup':
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case 'touchend':
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this.onTouchEnd(evt);
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break;
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case 'click':
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evt.stopPropagation();
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evt.preventDefault();
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let target = evt.target;
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let view = target.ownerDocument ? target.ownerDocument.defaultView
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: target;
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view.removeEventListener('click', this, true, true);
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break;
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}
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},
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position: new Point(0 , 0),
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findPrimaryPointer: function cp_findPrimaryPointer(touches) {
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if (!('primaryPointerId' in this))
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return null;
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for (let i = 0; i < touches.length; i++) {
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if (touches[i].identifier === this.primaryPointerId) {
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return touches[i];
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}
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}
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return null;
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},
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onTouchStart: function cp_onTouchStart(evt) {
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let screenX, screenY;
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if (this.watchedEventsType == 'touch') {
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if ('primaryPointerId' in this) {
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return;
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}
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let firstTouch = evt.changedTouches[0];
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this.primaryPointerId = firstTouch.identifier;
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this.pointerDownTarget = firstTouch.target;
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screenX = firstTouch.screenX;
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screenY = firstTouch.screenY;
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} else {
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this.pointerDownTarget = evt.target;
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screenX = evt.screenX;
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screenY = evt.screenY;
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}
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this.dragging = true;
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this.panning = false;
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let oldTarget = this.target;
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[this.target, this.scrollCallback] = this.getPannable(this.pointerDownTarget);
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// If we found a target, that means we have found a scrollable subframe. In
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// this case, and if we are using async panning and zooming on the parent
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// frame, inform the pan/zoom controller that it should not attempt to
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// handle any touch events it gets until the next batch (meaning the next
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// time we get a touch end).
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if (this.target != null && this._asyncPanZoomForViewportFrame) {
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this.detectingScrolling = true;
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var os = Cc["@mozilla.org/observer-service;1"].getService(Ci.nsIObserverService);
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os.notifyObservers(docShell, 'detect-scrollable-subframe', null);
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}
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// If we have a pointer down target and we're not async
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// pan/zooming, we may need to fill in for EventStateManager in
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// setting the active state on the target element. Set a timer to
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// ensure the pointer-down target is active. (If it's already
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// active, the timer is a no-op.)
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if (this.pointerDownTarget !== null && !this.detectingScrolling) {
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// If there's no possibility this is a drag/pan, activate now.
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// Otherwise wait a little bit to see if the gesture isn't a
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// tap.
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if (this.target === null) {
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this.notify(this._activationTimer);
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} else {
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this._activationTimer.initWithCallback(this,
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this._activationDelayMs,
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Ci.nsITimer.TYPE_ONE_SHOT);
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}
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}
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// If there is a pan animation running (from a previous pan gesture) and
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// the user touch back the screen, stop this animation immediatly and
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// prevent the possible click action if the touch happens on the same
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// target.
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this.preventNextClick = false;
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if (KineticPanning.active) {
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KineticPanning.stop();
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if (oldTarget && oldTarget == this.target)
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this.preventNextClick = true;
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}
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this.position.set(screenX, screenY);
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KineticPanning.record(new Point(0, 0), evt.timeStamp);
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},
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onTouchEnd: function cp_onTouchEnd(evt) {
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let touch = null;
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if (!this.dragging ||
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(this.watchedEventsType == 'touch' &&
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!(touch = this.findPrimaryPointer(evt.changedTouches)))) {
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return;
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}
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// !isPan() and evt.detail should always give the same answer here
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// since they use the same heuristics, but use the native gecko
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// computation when possible.
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//
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// NB: when we're using touch events, then !KineticPanning.isPan()
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// => this.panning, so we'll never attempt to block the click
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// event. That's OK however, because we won't fire a synthetic
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// click when we're using touch events and this touch series
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// wasn't a "tap" gesture.
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let click = (this.watchedEventsType == 'mouse') ?
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evt.detail : !KineticPanning.isPan();
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// Additionally, if we're seeing non-compliant hybrid events, a
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// "real" click will be generated if we started and ended on the
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// same element.
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if (this.hybridEvents) {
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let target =
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content.document.elementFromPoint(touch.clientX, touch.clientY);
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click |= (target === this.pointerDownTarget);
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}
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if (this.target && click && (this.panning || this.preventNextClick)) {
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let target = this.target;
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let view = target.ownerDocument ? target.ownerDocument.defaultView
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: target;
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view.addEventListener('click', this, true, true);
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}
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this._finishPanning();
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// Now that we're done, avoid entraining the thing we just panned.
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this.pointerDownTarget = null;
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},
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// True when there's an async pan-zoom controll watching the
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// outermost scrollable frame, and we're waiting to see whether
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// we're going to take over from it and synchronously scroll an
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// inner scrollable frame.
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detectingScrolling: false,
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onTouchMove: function cp_onTouchMove(evt) {
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if (!this.dragging)
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return;
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let screenX, screenY;
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if (this.watchedEventsType == 'touch') {
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let primaryTouch = this.findPrimaryPointer(evt.changedTouches);
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if (evt.touches.length > 1 || !primaryTouch)
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return;
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screenX = primaryTouch.screenX;
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screenY = primaryTouch.screenY;
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} else {
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screenX = evt.screenX;
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screenY = evt.screenY;
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}
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let current = this.position;
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let delta = new Point(screenX - current.x, screenY - current.y);
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current.set(screenX, screenY);
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KineticPanning.record(delta, evt.timeStamp);
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// There's no possibility of us panning anything.
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if (!this.scrollCallback) {
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return;
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}
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let isPan = KineticPanning.isPan();
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if (!isPan && this.detectingScrolling) {
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// If panning distance is not large enough and we're waiting to
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// see whether we should use the sync scroll fallback or not,
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// don't attempt scrolling.
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return;
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}
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let isScroll = this.scrollCallback(delta.scale(-1));
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if (this.detectingScrolling) {
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this.detectingScrolling = false;
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// Stop async-pan-zooming if the user is panning the subframe.
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if (isScroll) {
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// We're going to drive synchronously scrolling an inner frame.
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Services.obs.notifyObservers(docShell, 'cancel-default-pan-zoom', null);
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} else {
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// Let AsyncPanZoomController handle the scrolling gesture.
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this.scrollCallback = null;
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return;
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}
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}
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// If we've detected a pan gesture, cancel the active state of the
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// current target.
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if (!this.panning && isPan) {
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this.panning = true;
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this._resetActive();
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this._activationTimer.cancel();
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}
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if (this.panning) {
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// Only do this when we're actually executing a pan gesture.
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// Otherwise synthetic mouse events will be canceled.
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evt.stopPropagation();
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evt.preventDefault();
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}
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},
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// nsITimerCallback
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notify: function cp_notify(timer) {
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this._setActive(this.pointerDownTarget);
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},
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onKineticBegin: function cp_onKineticBegin(evt) {
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},
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onKineticPan: function cp_onKineticPan(delta) {
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return !this.scrollCallback(delta);
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},
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onKineticEnd: function cp_onKineticEnd() {
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if (!this.dragging)
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this.scrollCallback = null;
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},
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getPannable: function cp_getPannable(node) {
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let pannableNode = this._findPannable(node);
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if (pannableNode) {
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return [pannableNode, this._generateCallback(pannableNode)];
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}
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return [null, null];
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},
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_findPannable: function cp_findPannable(node) {
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if (!(node instanceof Ci.nsIDOMHTMLElement) || node.tagName == 'HTML') {
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return null;
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}
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let nodeContent = node.ownerDocument.defaultView;
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while (!(node instanceof Ci.nsIDOMHTMLBodyElement)) {
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let style = nodeContent.getComputedStyle(node, null);
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let overflow = [style.getPropertyValue('overflow'),
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style.getPropertyValue('overflow-x'),
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style.getPropertyValue('overflow-y')];
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let rect = node.getBoundingClientRect();
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let isAuto = (overflow.indexOf('auto') != -1 &&
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(rect.height < node.scrollHeight ||
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rect.width < node.scrollWidth));
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let isScroll = (overflow.indexOf('scroll') != -1);
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let isScrollableTextarea = (node.tagName == 'TEXTAREA' &&
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(node.scrollHeight > node.clientHeight ||
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node.scrollWidth > node.clientWidth ||
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('scrollLeftMax' in node && node.scrollLeftMax > 0) ||
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('scrollTopMax' in node && node.scrollTopMax > 0)));
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if (isScroll || isAuto || isScrollableTextarea) {
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return node;
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}
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node = node.parentNode;
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}
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if (ContentPanning._asyncPanZoomForViewportFrame &&
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nodeContent === content) {
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// The parent context is asynchronously panning and zooming our
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// root scrollable frame, so don't use our synchronous fallback.
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return null;
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}
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if (nodeContent.scrollMaxX || nodeContent.scrollMaxY) {
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return nodeContent;
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}
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if (nodeContent.frameElement) {
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return this._findPannable(nodeContent.frameElement);
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}
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return null;
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},
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_generateCallback: function cp_generateCallback(content) {
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let firstScroll = true;
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let target;
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let isScrolling = false;
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let oldX, oldY, newX, newY;
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let win, doc, htmlNode, bodyNode;
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let xScrollable;
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let yScrollable;
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function doScroll(node, delta) {
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// recalculate scrolling direction
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xScrollable = node.scrollWidth > node.clientWidth;
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yScrollable = node.scrollHeight > node.clientHeight;
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if (node instanceof Ci.nsIDOMHTMLElement) {
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newX = oldX = node.scrollLeft, newY = oldY = node.scrollTop;
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if (xScrollable) {
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node.scrollLeft += delta.x;
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newX = node.scrollLeft;
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}
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if (yScrollable) {
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node.scrollTop += delta.y;
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newY = node.scrollTop;
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}
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return (newX != oldX || newY != oldY);
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} else if (node instanceof Ci.nsIDOMWindow) {
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win = node;
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doc = win.document;
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// "overflow:hidden" on either the <html> or the <body> node should
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// prevent the user from scrolling the root viewport.
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if (doc instanceof Ci.nsIDOMHTMLDocument) {
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htmlNode = doc.documentElement;
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bodyNode = doc.body;
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if (win.getComputedStyle(htmlNode, null).overflowX == "hidden" ||
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win.getComputedStyle(bodyNode, null).overflowX == "hidden") {
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delta.x = 0;
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}
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if (win.getComputedStyle(htmlNode, null).overflowY == "hidden" ||
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win.getComputedStyle(bodyNode, null).overflowY == "hidden") {
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delta.y = 0;
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}
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}
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oldX = node.scrollX, oldY = node.scrollY;
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node.scrollBy(delta.x, delta.y);
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newX = node.scrollX, newY = node.scrollY;
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return (newX != oldX || newY != oldY);
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}
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// If we get here, |node| isn't an HTML element and it's not a window,
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// but findPannable apparently thought it was scrollable... What is it?
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return false;
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};
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function targetParent(node) {
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if (node.parentNode) {
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return node.parentNode;
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}
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if (node.frameElement) {
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return node.frameElement;
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}
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return null;
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}
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function scroll(delta) {
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for (target = content; target;
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target = ContentPanning._findPannable(targetParent(target))) {
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isScrolling = doScroll(target, delta);
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if (isScrolling || !firstScroll) {
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break;
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}
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}
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if (isScrolling) {
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if (firstScroll) {
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content = target; // set scrolling target to the first scrolling region
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}
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firstScroll = false; // lockdown the scrolling target after a success scrolling
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}
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return isScrolling;
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}
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return scroll;
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},
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get _domUtils() {
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delete this._domUtils;
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return this._domUtils = Cc['@mozilla.org/inspector/dom-utils;1']
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.getService(Ci.inIDOMUtils);
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},
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get _activationTimer() {
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delete this._activationTimer;
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return this._activationTimer = Cc["@mozilla.org/timer;1"]
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.createInstance(Ci.nsITimer);
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},
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get _activationDelayMs() {
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let delay = Services.prefs.getIntPref('ui.touch_activation.delay_ms');
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delete this._activationDelayMs;
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return this._activationDelayMs = delay;
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},
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_resetActive: function cp_resetActive() {
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let elt = this.target || this.pointerDownTarget;
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let root = elt.ownerDocument || elt.document;
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this._setActive(root.documentElement);
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},
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_setActive: function cp_setActive(elt) {
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const kStateActive = 0x00000001;
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this._domUtils.setContentState(elt, kStateActive);
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},
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get _asyncPanZoomForViewportFrame() {
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return docShell.asyncPanZoomEnabled;
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},
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_recvViewportChange: function(data) {
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let metrics = data.json;
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this._viewport = new Rect(metrics.x, metrics.y,
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metrics.viewport.width,
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metrics.viewport.height);
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this._cssCompositedRect = new Rect(metrics.x, metrics.y,
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metrics.cssCompositedRect.width,
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metrics.cssCompositedRect.height);
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this._cssPageRect = new Rect(metrics.cssPageRect.x,
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metrics.cssPageRect.y,
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metrics.cssPageRect.width,
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metrics.cssPageRect.height);
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},
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_recvDoubleTap: function(data) {
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let data = data.json;
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// We haven't received a metrics update yet; don't do anything.
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if (this._viewport == null) {
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return;
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}
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let win = content;
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let element = ElementTouchHelper.anyElementFromPoint(win, data.x, data.y);
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|
if (!element) {
|
|
this._zoomOut();
|
|
return;
|
|
}
|
|
|
|
while (element && !this._shouldZoomToElement(element))
|
|
element = element.parentNode;
|
|
|
|
if (!element) {
|
|
this._zoomOut();
|
|
} else {
|
|
const margin = 15;
|
|
let rect = ElementTouchHelper.getBoundingContentRect(element);
|
|
|
|
let cssPageRect = this._cssPageRect;
|
|
let viewport = this._viewport;
|
|
let bRect = new Rect(Math.max(cssPageRect.x, rect.x - margin),
|
|
rect.y,
|
|
rect.w + 2 * margin,
|
|
rect.h);
|
|
// constrict the rect to the screen's right edge
|
|
bRect.width = Math.min(bRect.width, cssPageRect.right - bRect.x);
|
|
|
|
// if the rect is already taking up most of the visible area and is stretching the
|
|
// width of the page, then we want to zoom out instead.
|
|
if (this._isRectZoomedIn(bRect, this._cssCompositedRect)) {
|
|
this._zoomOut();
|
|
return;
|
|
}
|
|
|
|
rect.x = Math.round(bRect.x);
|
|
rect.y = Math.round(bRect.y);
|
|
rect.w = Math.round(bRect.width);
|
|
rect.h = Math.round(bRect.height);
|
|
|
|
// if the block we're zooming to is really tall, and the user double-tapped
|
|
// more than a screenful of height from the top of it, then adjust the y-coordinate
|
|
// so that we center the actual point the user double-tapped upon. this prevents
|
|
// flying to the top of a page when double-tapping to zoom in (bug 761721).
|
|
// the 1.2 multiplier is just a little fuzz to compensate for bRect including horizontal
|
|
// margins but not vertical ones.
|
|
let cssTapY = viewport.y + data.y;
|
|
if ((bRect.height > rect.h) && (cssTapY > rect.y + (rect.h * 1.2))) {
|
|
rect.y = cssTapY - (rect.h / 2);
|
|
}
|
|
|
|
var os = Cc["@mozilla.org/observer-service;1"].getService(Ci.nsIObserverService);
|
|
os.notifyObservers(docShell, 'browser-zoom-to-rect', JSON.stringify(rect));
|
|
}
|
|
},
|
|
|
|
_shouldZoomToElement: function(aElement) {
|
|
let win = aElement.ownerDocument.defaultView;
|
|
if (win.getComputedStyle(aElement, null).display == "inline")
|
|
return false;
|
|
if (aElement instanceof Ci.nsIDOMHTMLLIElement)
|
|
return false;
|
|
if (aElement instanceof Ci.nsIDOMHTMLQuoteElement)
|
|
return false;
|
|
return true;
|
|
},
|
|
|
|
_zoomOut: function() {
|
|
let rect = new Rect(0, 0, 0, 0);
|
|
var os = Cc["@mozilla.org/observer-service;1"].getService(Ci.nsIObserverService);
|
|
os.notifyObservers(docShell, 'browser-zoom-to-rect', JSON.stringify(rect));
|
|
},
|
|
|
|
_isRectZoomedIn: function(aRect, aViewport) {
|
|
// This function checks to see if the area of the rect visible in the
|
|
// viewport (i.e. the "overlapArea" variable below) is approximately
|
|
// the max area of the rect we can show.
|
|
let vRect = new Rect(aViewport.x, aViewport.y, aViewport.width, aViewport.height);
|
|
let overlap = vRect.intersect(aRect);
|
|
let overlapArea = overlap.width * overlap.height;
|
|
let availHeight = Math.min(aRect.width * vRect.height / vRect.width, aRect.height);
|
|
let showing = overlapArea / (aRect.width * availHeight);
|
|
let ratioW = (aRect.width / vRect.width);
|
|
let ratioH = (aRect.height / vRect.height);
|
|
|
|
return (showing > 0.9 && (ratioW > 0.9 || ratioH > 0.9));
|
|
},
|
|
|
|
_finishPanning: function() {
|
|
this._resetActive();
|
|
this.dragging = false;
|
|
this.detectingScrolling = false;
|
|
delete this.primaryPointerId;
|
|
this._activationTimer.cancel();
|
|
|
|
if (this.panning) {
|
|
KineticPanning.start(this);
|
|
}
|
|
}
|
|
};
|
|
|
|
ContentPanning.init();
|
|
|
|
// Min/max velocity of kinetic panning. This is in pixels/millisecond.
|
|
const kMinVelocity = 0.2;
|
|
const kMaxVelocity = 6;
|
|
|
|
// Constants that affect the "friction" of the scroll pane.
|
|
const kExponentialC = 1000;
|
|
const kPolynomialC = 100 / 1000000;
|
|
|
|
// How often do we change the position of the scroll pane?
|
|
// Too often and panning may jerk near the end.
|
|
// Too little and panning will be choppy. In milliseconds.
|
|
const kUpdateInterval = 16;
|
|
|
|
// The numbers of momentums to use for calculating the velocity of the pan.
|
|
// Those are taken from the end of the action
|
|
const kSamples = 5;
|
|
|
|
const KineticPanning = {
|
|
_position: new Point(0, 0),
|
|
_velocity: new Point(0, 0),
|
|
_acceleration: new Point(0, 0),
|
|
|
|
get active() {
|
|
return this.target !== null;
|
|
},
|
|
|
|
target: null,
|
|
start: function kp_start(target) {
|
|
this.target = target;
|
|
|
|
// Calculate the initial velocity of the movement based on user input
|
|
let momentums = this.momentums;
|
|
let flick = momentums[momentums.length - 1].time - momentums[0].time < 300;
|
|
|
|
let distance = new Point(0, 0);
|
|
momentums.forEach(function(momentum) {
|
|
distance.add(momentum.dx, momentum.dy);
|
|
});
|
|
|
|
function clampFromZero(x, min, max) {
|
|
if (x >= 0)
|
|
return Math.max(min, Math.min(max, x));
|
|
return Math.min(-min, Math.max(-max, x));
|
|
}
|
|
|
|
let elapsed = momentums[momentums.length - 1].time - momentums[0].time;
|
|
let velocityX = clampFromZero(distance.x / elapsed, 0, kMaxVelocity);
|
|
let velocityY = clampFromZero(distance.y / elapsed, 0, kMaxVelocity);
|
|
|
|
let velocity = this._velocity;
|
|
if (flick) {
|
|
// Very fast pan action that does not generate a click are very often pan
|
|
// action. If this is a small gesture then it will not move the view a lot
|
|
// and so it will be above the minimun threshold and not generate any
|
|
// kinetic panning. This does not look on a device since this is often
|
|
// a real gesture, so let's lower the velocity threshold for such moves.
|
|
velocity.set(velocityX, velocityY);
|
|
} else {
|
|
velocity.set(Math.abs(velocityX) < kMinVelocity ? 0 : velocityX,
|
|
Math.abs(velocityY) < kMinVelocity ? 0 : velocityY);
|
|
}
|
|
this.momentums = [];
|
|
|
|
// Set acceleration vector to opposite signs of velocity
|
|
function sign(x) {
|
|
return x ? (x > 0 ? 1 : -1) : 0;
|
|
}
|
|
|
|
this._acceleration.set(velocity.clone().map(sign).scale(-kPolynomialC));
|
|
|
|
// Reset the position
|
|
this._position.set(0, 0);
|
|
|
|
this._startAnimation();
|
|
|
|
this.target.onKineticBegin();
|
|
},
|
|
|
|
stop: function kp_stop() {
|
|
if (!this.target)
|
|
return;
|
|
|
|
this.momentums = [];
|
|
this.distance.set(0, 0);
|
|
|
|
this.target.onKineticEnd();
|
|
this.target = null;
|
|
},
|
|
|
|
momentums: [],
|
|
record: function kp_record(delta, timestamp) {
|
|
this.momentums.push({ 'time': this._getTime(timestamp),
|
|
'dx' : delta.x, 'dy' : delta.y });
|
|
|
|
// We only need to keep kSamples in this.momentums.
|
|
if (this.momentums.length > kSamples) {
|
|
this.momentums.shift();
|
|
}
|
|
|
|
this.distance.add(delta.x, delta.y);
|
|
},
|
|
|
|
_getTime: function kp_getTime(time) {
|
|
// Touch events generated by the platform or hand-made are defined in
|
|
// microseconds instead of milliseconds. Bug 77992 will fix this at the
|
|
// platform level.
|
|
if (time > Date.now()) {
|
|
return Math.floor(time / 1000);
|
|
} else {
|
|
return time;
|
|
}
|
|
},
|
|
|
|
get threshold() {
|
|
let dpi = content.QueryInterface(Ci.nsIInterfaceRequestor)
|
|
.getInterface(Ci.nsIDOMWindowUtils)
|
|
.displayDPI;
|
|
|
|
let threshold = Services.prefs.getIntPref('ui.dragThresholdX') / 240 * dpi;
|
|
|
|
delete this.threshold;
|
|
return this.threshold = threshold;
|
|
},
|
|
|
|
distance: new Point(0, 0),
|
|
isPan: function cp_isPan() {
|
|
return (Math.abs(this.distance.x) > this.threshold ||
|
|
Math.abs(this.distance.y) > this.threshold);
|
|
},
|
|
|
|
_startAnimation: function kp_startAnimation() {
|
|
let c = kExponentialC;
|
|
function getNextPosition(position, v, a, t) {
|
|
// Important traits for this function:
|
|
// p(t=0) is 0
|
|
// p'(t=0) is v0
|
|
//
|
|
// We use exponential to get a smoother stop, but by itself exponential
|
|
// is too smooth at the end. Adding a polynomial with the appropriate
|
|
// weight helps to balance
|
|
position.set(v.x * Math.exp(-t / c) * -c + a.x * t * t + v.x * c,
|
|
v.y * Math.exp(-t / c) * -c + a.y * t * t + v.y * c);
|
|
}
|
|
|
|
let startTime = content.mozAnimationStartTime;
|
|
let elapsedTime = 0, targetedTime = 0, averageTime = 0;
|
|
|
|
let velocity = this._velocity;
|
|
let acceleration = this._acceleration;
|
|
|
|
let position = this._position;
|
|
let nextPosition = new Point(0, 0);
|
|
let delta = new Point(0, 0);
|
|
|
|
let callback = (function(timestamp) {
|
|
if (!this.target)
|
|
return;
|
|
|
|
// To make animation end fast enough but to keep smoothness, average the
|
|
// ideal time frame (smooth animation) with the actual time lapse
|
|
// (end fast enough).
|
|
// Animation will never take longer than 2 times the ideal length of time.
|
|
elapsedTime = timestamp - startTime;
|
|
targetedTime += kUpdateInterval;
|
|
averageTime = (targetedTime + elapsedTime) / 2;
|
|
|
|
// Calculate new position.
|
|
getNextPosition(nextPosition, velocity, acceleration, averageTime);
|
|
delta.set(Math.round(nextPosition.x - position.x),
|
|
Math.round(nextPosition.y - position.y));
|
|
|
|
// Test to see if movement is finished for each component.
|
|
if (delta.x * acceleration.x > 0)
|
|
delta.x = position.x = velocity.x = acceleration.x = 0;
|
|
|
|
if (delta.y * acceleration.y > 0)
|
|
delta.y = position.y = velocity.y = acceleration.y = 0;
|
|
|
|
if (velocity.equals(0, 0) || delta.equals(0, 0)) {
|
|
this.stop();
|
|
return;
|
|
}
|
|
|
|
position.add(delta);
|
|
if (this.target.onKineticPan(delta.scale(-1))) {
|
|
this.stop();
|
|
return;
|
|
}
|
|
|
|
content.mozRequestAnimationFrame(callback);
|
|
}).bind(this);
|
|
|
|
content.mozRequestAnimationFrame(callback);
|
|
}
|
|
};
|
|
|
|
const ElementTouchHelper = {
|
|
anyElementFromPoint: function(aWindow, aX, aY) {
|
|
let cwu = aWindow.QueryInterface(Ci.nsIInterfaceRequestor).getInterface(Ci.nsIDOMWindowUtils);
|
|
let elem = cwu.elementFromPoint(aX, aY, true, true);
|
|
|
|
let HTMLIFrameElement = Ci.nsIDOMHTMLIFrameElement;
|
|
let HTMLFrameElement = Ci.nsIDOMHTMLFrameElement;
|
|
while (elem && (elem instanceof HTMLIFrameElement || elem instanceof HTMLFrameElement)) {
|
|
let rect = elem.getBoundingClientRect();
|
|
aX -= rect.left;
|
|
aY -= rect.top;
|
|
cwu = elem.contentDocument.defaultView.QueryInterface(Ci.nsIInterfaceRequestor).getInterface(Ci.nsIDOMWindowUtils);
|
|
elem = cwu.elementFromPoint(aX, aY, true, true);
|
|
}
|
|
|
|
return elem;
|
|
},
|
|
|
|
getBoundingContentRect: function(aElement) {
|
|
if (!aElement)
|
|
return {x: 0, y: 0, w: 0, h: 0};
|
|
|
|
let document = aElement.ownerDocument;
|
|
while (document.defaultView.frameElement)
|
|
document = document.defaultView.frameElement.ownerDocument;
|
|
|
|
let cwu = document.defaultView.QueryInterface(Ci.nsIInterfaceRequestor).getInterface(Ci.nsIDOMWindowUtils);
|
|
let scrollX = {}, scrollY = {};
|
|
cwu.getScrollXY(false, scrollX, scrollY);
|
|
|
|
let r = aElement.getBoundingClientRect();
|
|
|
|
// step out of iframes and frames, offsetting scroll values
|
|
for (let frame = aElement.ownerDocument.defaultView; frame.frameElement && frame != content; frame = frame.parent) {
|
|
// adjust client coordinates' origin to be top left of iframe viewport
|
|
let rect = frame.frameElement.getBoundingClientRect();
|
|
let left = frame.getComputedStyle(frame.frameElement, "").borderLeftWidth;
|
|
let top = frame.getComputedStyle(frame.frameElement, "").borderTopWidth;
|
|
scrollX.value += rect.left + parseInt(left);
|
|
scrollY.value += rect.top + parseInt(top);
|
|
}
|
|
|
|
return {x: r.left + scrollX.value,
|
|
y: r.top + scrollY.value,
|
|
w: r.width,
|
|
h: r.height };
|
|
}
|
|
};
|