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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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 */
#include "mozilla/dom/SVGAnimationElement.h"
#include "mozilla/SMILMilestone.h"
#include "mozilla/SMILTypes.h"
#include "nscore.h"
#include "nsTPriorityQueue.h"
namespace mozilla {
class SMILTimeValue;
// SMILTimeContainer
// Common base class for a time base that can be paused, resumed, and sampled.
class SMILTimeContainer {
virtual ~SMILTimeContainer();
* 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(uint32_t 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(uint32_t 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(uint32_t 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.
SMILTime GetCurrentTimeAsSMILTime() 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(SMILTime aSeekTo);
* Return the current time for the parent time container if any.
virtual SMILTime 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.
SMILTimeValue ContainerToParentTime(SMILTime 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.
SMILTimeValue ParentToContainerTime(SMILTime 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(SMILTimeContainer* 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.
void AddMilestone(const SMILMilestone& aMilestone,
mozilla::dom::SVGAnimationElement& 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(SMILMilestone& aNextMilestone) const;
using AnimElemArray = nsTArray<RefPtr<dom::SVGAnimationElement>>;
* 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 SMILMilestone& aMilestone,
AnimElemArray& aMatchedElements);
// Cycle-collection support
void Traverse(nsCycleCollectionTraversalCallback* aCallback);
void Unlink();
* 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(SMILTimeContainer& aChild) {
* Removes a child time container.
virtual void RemoveChild(SMILTimeContainer& 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
SMILTimeContainer* mParent;
// The current time established at the last call to Sample()
SMILTime 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
SMILTime mParentOffset;
// The timestamp in parent time when the container was paused
SMILTime 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
#ifdef DEBUG
bool mHoldingEntries; // True if there's a raw pointer to mMilestoneEntries
// on the stack.
// A bitfield of the pause state for all pause requests
uint32_t mPauseState;
struct MilestoneEntry {
MilestoneEntry(const SMILMilestone& aMilestone,
mozilla::dom::SVGAnimationElement& aElement)
: mMilestone(aMilestone), mTimebase(&aElement) {}
bool operator<(const MilestoneEntry& aOther) const {
return mMilestone < aOther.mMilestone;
SMILMilestone mMilestone; // In container time.
RefPtr<mozilla::dom::SVGAnimationElement> 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;
} // namespace mozilla