/* vim: set shiftwidth=2 tabstop=8 autoindent cindent expandtab: */ /* ***** BEGIN LICENSE BLOCK ***** * Version: MPL 1.1/GPL 2.0/LGPL 2.1 * * The contents of this file are subject to the Mozilla Public License Version * 1.1 (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * http://www.mozilla.org/MPL/ * * Software distributed under the License is distributed on an "AS IS" basis, * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License * for the specific language governing rights and limitations under the * License. * * The Original Code is nsRefreshDriver. * * The Initial Developer of the Original Code is the Mozilla Foundation. * Portions created by the Initial Developer are Copyright (C) 2009 * the Initial Developer. All Rights Reserved. * * Contributor(s): * L. David Baron , Mozilla Corporation (original author) * * Alternatively, the contents of this file may be used under the terms of * either the GNU General Public License Version 2 or later (the "GPL"), or * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), * in which case the provisions of the GPL or the LGPL are applicable instead * of those above. If you wish to allow use of your version of this file only * under the terms of either the GPL or the LGPL, and not to allow others to * use your version of this file under the terms of the MPL, indicate your * decision by deleting the provisions above and replace them with the notice * and other provisions required by the GPL or the LGPL. If you do not delete * the provisions above, a recipient may use your version of this file under * the terms of any one of the MPL, the GPL or the LGPL. * * ***** END LICENSE BLOCK ***** */ /* * Code to notify things that animate before a refresh, at an appropriate * refresh rate. (Perhaps temporary, until replaced by compositor.) */ #ifndef nsRefreshDriver_h_ #define nsRefreshDriver_h_ #include "mozilla/TimeStamp.h" #include "mozFlushType.h" #include "nsITimer.h" #include "nsCOMPtr.h" #include "nsTObserverArray.h" #include "nsTArray.h" #include "nsAutoPtr.h" class nsPresContext; class nsIPresShell; class nsIDocument; /** * An abstract base class to be implemented by callers wanting to be * notified at refresh times. When nothing needs to be painted, callers * may not be notified. */ class nsARefreshObserver { public: // AddRef and Release signatures that match nsISupports. Implementors // must implement reference counting, and those that do implement // nsISupports will already have methods with the correct signature. // // The refresh driver does NOT hold references to refresh observers // except while it is notifying them. NS_IMETHOD_(nsrefcnt) AddRef(void) = 0; NS_IMETHOD_(nsrefcnt) Release(void) = 0; virtual void WillRefresh(mozilla::TimeStamp aTime) = 0; }; class nsRefreshDriver : public nsITimerCallback { public: nsRefreshDriver(nsPresContext *aPresContext); ~nsRefreshDriver(); // nsISupports implementation NS_DECL_ISUPPORTS // nsITimerCallback implementation NS_DECL_NSITIMERCALLBACK /** * Return the time of the most recent refresh. This is intended to be * used by callers who want to start an animation now and want to know * what time to consider the start of the animation. (This helps * ensure that multiple animations started during the same event off * the main event loop have the same start time.) */ mozilla::TimeStamp MostRecentRefresh() const; /** * Same thing, but in microseconds since the epoch. */ PRInt64 MostRecentRefreshEpochTime() const; /** * Add / remove refresh observers. Returns whether the operation * succeeded. * * The flush type affects: * + the order in which the observers are notified (lowest flush * type to highest, in order registered) * + (in the future) which observers are suppressed when the display * doesn't require current position data or isn't currently * painting, and, correspondingly, which get notified when there * is a flush during such suppression * and it must be either Flush_Style, Flush_Layout, or Flush_Display. * * The refresh driver does NOT own a reference to these observers; * they must remove themselves before they are destroyed. */ PRBool AddRefreshObserver(nsARefreshObserver *aObserver, mozFlushType aFlushType); PRBool RemoveRefreshObserver(nsARefreshObserver *aObserver, mozFlushType aFlushType); /** * Add / remove presshells that we should flush style and layout on */ PRBool AddStyleFlushObserver(nsIPresShell* aShell) { NS_ASSERTION(!mStyleFlushObservers.Contains(aShell), "Double-adding style flush observer"); PRBool appended = mStyleFlushObservers.AppendElement(aShell) != nsnull; EnsureTimerStarted(); return appended; } void RemoveStyleFlushObserver(nsIPresShell* aShell) { mStyleFlushObservers.RemoveElement(aShell); } PRBool AddLayoutFlushObserver(nsIPresShell* aShell) { NS_ASSERTION(!IsLayoutFlushObserver(aShell), "Double-adding layout flush observer"); PRBool appended = mLayoutFlushObservers.AppendElement(aShell) != nsnull; EnsureTimerStarted(); return appended; } void RemoveLayoutFlushObserver(nsIPresShell* aShell) { mLayoutFlushObservers.RemoveElement(aShell); } PRBool IsLayoutFlushObserver(nsIPresShell* aShell) { return mLayoutFlushObservers.Contains(aShell); } /** * Add a document for which we should fire a MozBeforePaint event. */ PRBool ScheduleBeforePaintEvent(nsIDocument* aDocument); /** * Add a document for which we have nsIAnimationFrameListeners */ void ScheduleAnimationFrameListeners(nsIDocument* aDocument); /** * Remove a document for which we should fire a MozBeforePaint event. */ void RevokeBeforePaintEvent(nsIDocument* aDocument); /** * Remove a document for which we have nsIAnimationFrameListeners */ void RevokeAnimationFrameListeners(nsIDocument* aDocument); /** * Tell the refresh driver that it is done driving refreshes and * should stop its timer and forget about its pres context. This may * be called from within a refresh. */ void Disconnect() { StopTimer(); mPresContext = nsnull; } /** * Freeze the refresh driver. It should stop delivering future * refreshes until thawed. */ void Freeze(); /** * Thaw the refresh driver. If needed, it should start delivering * refreshes again. */ void Thaw(); /** * Throttle or unthrottle the refresh driver. This is done if the * corresponding presshell is hidden or shown. */ void SetThrottled(bool aThrottled); /** * Return the prescontext we were initialized with */ nsPresContext* PresContext() const { return mPresContext; } #ifdef DEBUG /** * Check whether the given observer is an observer for the given flush type */ PRBool IsRefreshObserver(nsARefreshObserver *aObserver, mozFlushType aFlushType); #endif private: typedef nsTObserverArray ObserverArray; void EnsureTimerStarted(); void StopTimer(); PRUint32 ObserverCount() const; void UpdateMostRecentRefresh(); ObserverArray& ArrayFor(mozFlushType aFlushType); // Trigger a refresh immediately, if haven't been disconnected or frozen. void DoRefresh(); PRInt32 GetRefreshTimerInterval() const; PRInt32 GetRefreshTimerType() const; nsCOMPtr mTimer; mozilla::TimeStamp mMostRecentRefresh; // only valid when mTimer non-null PRInt64 mMostRecentRefreshEpochTime; // same thing as mMostRecentRefresh, // but in microseconds since the epoch. nsPresContext *mPresContext; // weak; pres context passed in constructor // and unset in Disconnect bool mFrozen; bool mThrottled; // separate arrays for each flush type we support ObserverArray mObservers[3]; nsAutoTArray mStyleFlushObservers; nsAutoTArray mLayoutFlushObservers; // nsTArray on purpose, because we want to be able to swap. nsTArray mBeforePaintTargets; // nsTArray on purpose, because we want to be able to swap. nsTArray mAnimationFrameListenerDocs; // This is the last interval we used for our timer. May be 0 if we // haven't computed a timer interval yet. mutable PRInt32 mLastTimerInterval; }; #endif /* !defined(nsRefreshDriver_h_) */