gecko-dev/content/smil/nsSMILTimeContainer.h
2012-05-21 12:12:37 +01:00

297 lines
9.2 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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/. */
#ifndef NS_SMILTIMECONTAINER_H_
#define NS_SMILTIMECONTAINER_H_
#include "nscore.h"
#include "nsSMILTypes.h"
#include "nsTPriorityQueue.h"
#include "nsAutoPtr.h"
#include "nsISMILAnimationElement.h"
#include "nsSMILMilestone.h"
class nsSMILTimeValue;
//----------------------------------------------------------------------
// nsSMILTimeContainer
//
// Common base class for a time base that can be paused, resumed, and sampled.
//
class nsSMILTimeContainer
{
public:
nsSMILTimeContainer();
virtual ~nsSMILTimeContainer();
/*
* Pause request types.
*/
enum {
PAUSE_BEGIN = 1, // Paused because timeline has yet to begin.
PAUSE_SCRIPT = 2, // Paused by script.
PAUSE_PAGEHIDE = 4, // Paused because our doc is hidden.
PAUSE_USERPREF = 8, // Paused because animations are disabled in prefs.
PAUSE_IMAGE = 16 // Paused becuase we're in an image that's suspended.
};
/*
* Cause the time container to record its begin time.
*/
void Begin();
/*
* Pause this time container
*
* @param aType The source of the pause request. Successive calls to Pause
* with the same aType will be ignored. The container will remain paused until
* each call to Pause of a given aType has been matched by at least one call
* to Resume with the same aType.
*/
virtual void Pause(PRUint32 aType);
/*
* Resume this time container
*
* param @aType The source of the resume request. Clears the pause flag for
* this particular type of pause request. When all pause flags have been
* cleared the time container will be resumed.
*/
virtual void Resume(PRUint32 aType);
/**
* Returns true if this time container is paused by the specified type.
* Note that the time container may also be paused by other types; this method
* does not test if aType is the exclusive pause source.
*
* @param @aType The pause source to test for.
* @return true if this container is paused by aType.
*/
bool IsPausedByType(PRUint32 aType) const { return mPauseState & aType; }
/**
* Returns true if this time container is paused.
* Generally you should test for a specific type of pausing using
* IsPausedByType.
*
* @return true if this container is paused, false otherwise.
*/
bool IsPaused() const { return mPauseState != 0; }
/*
* Return the time elapsed since this time container's begin time (expressed
* in parent time) minus any accumulated offset from pausing.
*/
nsSMILTime GetCurrentTime() const;
/*
* Seek the document timeline to the specified time.
*
* @param aSeekTo The time to seek to, expressed in this time container's time
* base (i.e. the same units as GetCurrentTime).
*/
void SetCurrentTime(nsSMILTime aSeekTo);
/*
* Return the current time for the parent time container if any.
*/
virtual nsSMILTime GetParentTime() const;
/*
* Convert container time to parent time.
*
* @param aContainerTime The container time to convert.
* @return The equivalent parent time or indefinite if the container is
* paused and the time is in the future.
*/
nsSMILTimeValue ContainerToParentTime(nsSMILTime aContainerTime) const;
/*
* Convert from parent time to container time.
*
* @param aParentTime The parent time to convert.
* @return The equivalent container time or indefinite if the container is
* paused and aParentTime is after the time when the pause began.
*/
nsSMILTimeValue ParentToContainerTime(nsSMILTime aParentTime) const;
/*
* If the container is paused, causes the pause time to be updated to the
* current parent time. This should be called before updating
* cross-container dependencies that will call ContainerToParentTime in order
* to provide more intuitive results.
*/
void SyncPauseTime();
/*
* Updates the current time of this time container and calls DoSample to
* perform any sample-operations.
*/
void Sample();
/*
* Return if this time container should be sampled or can be skipped.
*
* This is most useful as an optimisation for skipping time containers that
* don't require a sample.
*/
bool NeedsSample() const { return !mPauseState || mNeedsPauseSample; }
/*
* Indicates if the elements of this time container need to be rewound.
* This occurs during a backwards seek.
*/
bool NeedsRewind() const { return mNeedsRewind; }
void ClearNeedsRewind() { mNeedsRewind = false; }
/*
* Indicates the time container is currently processing a SetCurrentTime
* request and appropriate seek behaviour should be applied by child elements
* (e.g. not firing time events).
*/
bool IsSeeking() const { return mIsSeeking; }
void MarkSeekFinished() { mIsSeeking = false; }
/*
* Sets the parent time container.
*
* The callee still retains ownership of the time container.
*/
nsresult SetParent(nsSMILTimeContainer* aParent);
/*
* Registers an element for a sample at the given time.
*
* @param aMilestone The milestone to register in container time.
* @param aElement The timebase element that needs a sample at
* aMilestone.
* @return true if the element was successfully added, false otherwise.
*/
bool AddMilestone(const nsSMILMilestone& aMilestone,
nsISMILAnimationElement& aElement);
/*
* Resets the list of milestones.
*/
void ClearMilestones();
/*
* Returns the next significant transition from amongst the registered
* milestones.
*
* @param[out] aNextMilestone The next milestone with time in parent time.
*
* @return true if there exists another milestone, false otherwise in
* which case aNextMilestone will be unmodified.
*/
bool GetNextMilestoneInParentTime(nsSMILMilestone& aNextMilestone) const;
typedef nsTArray<nsRefPtr<nsISMILAnimationElement> > AnimElemArray;
/*
* Removes and returns the timebase elements from the start of the list of
* timebase elements that match the given time.
*
* @param aMilestone The milestone time to match in parent time. This
* must be <= GetNextMilestoneInParentTime.
* @param[out] aMatchedElements The array to which matching elements will be
* appended.
* @return true if one or more elements match, false otherwise.
*/
bool PopMilestoneElementsAtMilestone(const nsSMILMilestone& aMilestone,
AnimElemArray& aMatchedElements);
// Cycle-collection support
void Traverse(nsCycleCollectionTraversalCallback* aCallback);
void Unlink();
protected:
/*
* Per-sample operations to be performed whenever Sample() is called and
* NeedsSample() is true. Called after updating mCurrentTime;
*/
virtual void DoSample() { }
/*
* Adding and removing child containers is not implemented in the base class
* because not all subclasses need this.
*/
/*
* Adds a child time container.
*/
virtual nsresult AddChild(nsSMILTimeContainer& aChild)
{
return NS_ERROR_FAILURE;
}
/*
* Removes a child time container.
*/
virtual void RemoveChild(nsSMILTimeContainer& aChild) { }
/*
* Implementation helper to update the current time.
*/
void UpdateCurrentTime();
/*
* Implementation helper to notify timed elements with dependencies that the
* container time has changed with respect to the document time.
*/
void NotifyTimeChange();
// The parent time container, if any
nsSMILTimeContainer* mParent;
// The current time established at the last call to Sample()
nsSMILTime mCurrentTime;
// The number of milliseconds for which the container has been paused
// (excluding the current pause interval if the container is currently
// paused).
//
// Current time = parent time - mParentOffset
//
nsSMILTime mParentOffset;
// The timestamp in parent time when the container was paused
nsSMILTime mPauseStart;
// Whether or not a pause sample is required
bool mNeedsPauseSample;
bool mNeedsRewind; // Backwards seek performed
bool mIsSeeking; // Currently in the middle of a seek operation
// A bitfield of the pause state for all pause requests
PRUint32 mPauseState;
struct MilestoneEntry
{
MilestoneEntry(nsSMILMilestone aMilestone,
nsISMILAnimationElement& aElement)
: mMilestone(aMilestone), mTimebase(&aElement)
{ }
bool operator<(const MilestoneEntry& aOther) const
{
return mMilestone < aOther.mMilestone;
}
nsSMILMilestone mMilestone; // In container time.
nsRefPtr<nsISMILAnimationElement> mTimebase;
};
// Queue of elements with registered milestones. Used to update the model with
// significant transitions that occur between two samples. Since timed element
// re-register their milestones when they're sampled this is reset once we've
// taken care of the milestones before the current sample time but before we
// actually do the full sample.
nsTPriorityQueue<MilestoneEntry> mMilestoneEntries;
};
#endif // NS_SMILTIMECONTAINER_H_