pjs/content/smil/nsSMILAnimationController.h

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 * 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
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 * License.
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 * The Original Code is the Mozilla SMIL module.
 *
 * The Initial Developer of the Original Code is Brian Birtles.
 * Portions created by the Initial Developer are Copyright (C) 2008
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Brian Birtles <birtles@gmail.com>
 *   Daniel Holbert <dholbert@mozilla.com>
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 * either of the GNU General Public License Version 2 or later (the "GPL"),
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#ifndef NS_SMILANIMATIONCONTROLLER_H_
#define NS_SMILANIMATIONCONTROLLER_H_

#include "nsAutoPtr.h"
#include "nsCOMPtr.h"
#include "nsTArray.h"
#include "nsITimer.h"
#include "nsTHashtable.h"
#include "nsHashKeys.h"
#include "nsSMILTimeContainer.h"
#include "nsSMILCompositorTable.h"

class nsISMILAnimationElement;
class nsIDocument;

//----------------------------------------------------------------------
// nsSMILAnimationController
// 
// The animation controller maintains the animation timer and determines the
// sample times and sample rate for all SMIL animations in a document. There is
// at most one animation controller per nsDocument so that frame-rate tuning can
// be performed at a document-level.
//
// The animation controller can contain many child time containers (timed
// document root objects) which may correspond to SVG document fragments within
// a compound document. These time containers can be paused individually or
// here, at the document level.
//
class nsSMILAnimationController : public nsSMILTimeContainer
{
public:
  nsSMILAnimationController();
  ~nsSMILAnimationController();

  // nsSMILContainer
  virtual void Pause(PRUint32 aType);
  virtual void Resume(PRUint32 aType);
  virtual nsSMILTime GetParentTime() const;
  
  // Methods for registering and enumerating animation elements
  void RegisterAnimationElement(nsISMILAnimationElement* aAnimationElement);
  void UnregisterAnimationElement(nsISMILAnimationElement* aAnimationElement);

  // Methods for resampling all animations
  // (A resample performs the same operations as a sample but doesn't advance
  // the current time and doesn't check if the container is paused)
  void Resample();
  void SetResampleNeeded() { mResampleNeeded = PR_TRUE; }
  void FlushResampleRequests()
  {
    if (!mResampleNeeded)
      return;

    DoSample(PR_FALSE); // Don't skip unchanged time containers--sample them all
  }

  // Methods for handling page transitions
  void OnPageShow();
  void OnPageHide();

  // Methods for supporting cycle-collection
  void Traverse(nsCycleCollectionTraversalCallback* aCallback);
  void Unlink();

protected:
  // Typedefs
  typedef nsPtrHashKey<nsSMILTimeContainer> TimeContainerPtrKey;
  typedef nsTHashtable<TimeContainerPtrKey> TimeContainerHashtable;
  typedef nsPtrHashKey<nsISMILAnimationElement> AnimationElementPtrKey;
  typedef nsTHashtable<AnimationElementPtrKey> AnimationElementHashtable;

  struct SampleTimeContainerParams
  {
    TimeContainerHashtable* mActiveContainers;
    PRBool                  mSkipUnchangedContainers;
  };

  struct SampleAnimationParams
  {
    TimeContainerHashtable* mActiveContainers;
    nsSMILCompositorTable*  mCompositorTable;
  };
  
  // Factory methods
  friend nsSMILAnimationController*
  NS_NewSMILAnimationController(nsIDocument* aDoc);
  nsresult    Init(nsIDocument* aDoc);

  // Cycle-collection implementation helpers
  PR_STATIC_CALLBACK(PLDHashOperator) CompositorTableEntryTraverse(
      nsSMILCompositor* aCompositor, void* aArg);

  // Timer-related implementation helpers
  static void Notify(nsITimer* aTimer, void* aClosure);
  nsresult    StartTimer();
  nsresult    StopTimer();

  // Sample-related callbacks and implementation helpers
  virtual void DoSample();
  void DoSample(PRBool aSkipUnchangedContainers);
  PR_STATIC_CALLBACK(PLDHashOperator) SampleTimeContainer(
      TimeContainerPtrKey* aKey, void* aData);
  PR_STATIC_CALLBACK(PLDHashOperator) SampleAnimation(
      AnimationElementPtrKey* aKey, void* aData);
  PR_STATIC_CALLBACK(PLDHashOperator) AddAnimationToCompositorTable(
      AnimationElementPtrKey* aKey, void* aData);
  static void SampleTimedElement(nsISMILAnimationElement* aElement,
                                 TimeContainerHashtable* aActiveContainers);
  static void AddAnimationToCompositorTable(
    nsISMILAnimationElement* aElement, nsSMILCompositorTable* aCompositorTable);
  static PRBool GetCompositorKeyForAnimation(nsISMILAnimationElement* aAnimElem,
                                             nsSMILCompositorKey& aResult);

  // Methods for adding/removing time containers
  virtual nsresult AddChild(nsSMILTimeContainer& aChild);
  virtual void     RemoveChild(nsSMILTimeContainer& aChild);

  // Members
  static const PRUint32      kTimerInterval;
  nsCOMPtr<nsITimer>         mTimer;
  AnimationElementHashtable  mAnimationElementTable;
  TimeContainerHashtable     mChildContainerTable;
  PRPackedBool               mResampleNeeded;
  
  // Store raw ptr to mDocument.  It owns the controller, so controller
  // shouldn't outlive it
  nsIDocument* mDocument;

  // Contains compositors used in our last sample.  We keep this around
  // so we can detect when an element/attribute used to be animated,
  // but isn't anymore for some reason. (e.g. if its <animate> element is 
  // removed or retargeted)
  nsAutoPtr<nsSMILCompositorTable> mLastCompositorTable;
};

nsSMILAnimationController* NS_NewSMILAnimationController(nsIDocument *doc);

#endif // NS_SMILANIMATIONCONTROLLER_H_