Bumping gaia.json for 2 gaia revision(s) a=gaia-bump
[gecko.git] / dom / smil / nsSMILTimeContainer.cpp
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1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2 /* This Source Code Form is subject to the terms of the Mozilla Public
3 * License, v. 2.0. If a copy of the MPL was not distributed with this
4 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6 #include "nsSMILTimeContainer.h"
7 #include "nsSMILTimeValue.h"
8 #include "nsSMILTimedElement.h"
9 #include <algorithm>
11 nsSMILTimeContainer::nsSMILTimeContainer()
13 mParent(nullptr),
14 mCurrentTime(0L),
15 mParentOffset(0L),
16 mPauseStart(0L),
17 mNeedsPauseSample(false),
18 mNeedsRewind(false),
19 mIsSeeking(false),
20 mPauseState(PAUSE_BEGIN)
24 nsSMILTimeContainer::~nsSMILTimeContainer()
26 if (mParent) {
27 mParent->RemoveChild(*this);
31 nsSMILTimeValue
32 nsSMILTimeContainer::ContainerToParentTime(nsSMILTime aContainerTime) const
34 // If we're paused, then future times are indefinite
35 if (IsPaused() && aContainerTime > mCurrentTime)
36 return nsSMILTimeValue::Indefinite();
38 return nsSMILTimeValue(aContainerTime + mParentOffset);
41 nsSMILTimeValue
42 nsSMILTimeContainer::ParentToContainerTime(nsSMILTime aParentTime) const
44 // If we're paused, then any time after when we paused is indefinite
45 if (IsPaused() && aParentTime > mPauseStart)
46 return nsSMILTimeValue::Indefinite();
48 return nsSMILTimeValue(aParentTime - mParentOffset);
51 void
52 nsSMILTimeContainer::Begin()
54 Resume(PAUSE_BEGIN);
55 if (mPauseState) {
56 mNeedsPauseSample = true;
59 // This is a little bit complicated here. Ideally we'd just like to call
60 // Sample() and force an initial sample but this turns out to be a bad idea
61 // because this may mean that NeedsSample() no longer reports true and so when
62 // we come to the first real sample our parent will skip us over altogether.
63 // So we force the time to be updated and adopt the policy to never call
64 // Sample() ourselves but to always leave that to our parent or client.
66 UpdateCurrentTime();
69 void
70 nsSMILTimeContainer::Pause(uint32_t aType)
72 bool didStartPause = false;
74 if (!mPauseState && aType) {
75 mPauseStart = GetParentTime();
76 mNeedsPauseSample = true;
77 didStartPause = true;
80 mPauseState |= aType;
82 if (didStartPause) {
83 NotifyTimeChange();
87 void
88 nsSMILTimeContainer::Resume(uint32_t aType)
90 if (!mPauseState)
91 return;
93 mPauseState &= ~aType;
95 if (!mPauseState) {
96 nsSMILTime extraOffset = GetParentTime() - mPauseStart;
97 mParentOffset += extraOffset;
98 NotifyTimeChange();
102 nsSMILTime
103 nsSMILTimeContainer::GetCurrentTime() const
105 // The following behaviour is consistent with:
106 // http://www.w3.org/2003/01/REC-SVG11-20030114-errata
107 // #getCurrentTime_setCurrentTime_undefined_before_document_timeline_begin
108 // which says that if GetCurrentTime is called before the document timeline
109 // has begun we should just return 0.
110 if (IsPausedByType(PAUSE_BEGIN))
111 return 0L;
113 return mCurrentTime;
116 void
117 nsSMILTimeContainer::SetCurrentTime(nsSMILTime aSeekTo)
119 // SVG 1.1 doesn't specify what to do for negative times so we adopt SVGT1.2's
120 // behaviour of clamping negative times to 0.
121 aSeekTo = std::max<nsSMILTime>(0, aSeekTo);
123 // The following behaviour is consistent with:
124 // http://www.w3.org/2003/01/REC-SVG11-20030114-errata
125 // #getCurrentTime_setCurrentTime_undefined_before_document_timeline_begin
126 // which says that if SetCurrentTime is called before the document timeline
127 // has begun we should still adjust the offset.
128 nsSMILTime parentTime = GetParentTime();
129 mParentOffset = parentTime - aSeekTo;
130 mIsSeeking = true;
132 if (IsPaused()) {
133 mNeedsPauseSample = true;
134 mPauseStart = parentTime;
137 if (aSeekTo < mCurrentTime) {
138 // Backwards seek
139 mNeedsRewind = true;
140 ClearMilestones();
143 // Force an update to the current time in case we get a call to GetCurrentTime
144 // before another call to Sample().
145 UpdateCurrentTime();
147 NotifyTimeChange();
150 nsSMILTime
151 nsSMILTimeContainer::GetParentTime() const
153 if (mParent)
154 return mParent->GetCurrentTime();
156 return 0L;
159 void
160 nsSMILTimeContainer::SyncPauseTime()
162 if (IsPaused()) {
163 nsSMILTime parentTime = GetParentTime();
164 nsSMILTime extraOffset = parentTime - mPauseStart;
165 mParentOffset += extraOffset;
166 mPauseStart = parentTime;
170 void
171 nsSMILTimeContainer::Sample()
173 if (!NeedsSample())
174 return;
176 UpdateCurrentTime();
177 DoSample();
179 mNeedsPauseSample = false;
182 nsresult
183 nsSMILTimeContainer::SetParent(nsSMILTimeContainer* aParent)
185 if (mParent) {
186 mParent->RemoveChild(*this);
187 // When we're not attached to a parent time container, GetParentTime() will
188 // return 0. We need to adjust our pause state information to be relative to
189 // this new time base.
190 // Note that since "current time = parent time - parent offset" setting the
191 // parent offset and pause start as follows preserves our current time even
192 // while parent time = 0.
193 mParentOffset = -mCurrentTime;
194 mPauseStart = 0L;
197 mParent = aParent;
199 nsresult rv = NS_OK;
200 if (mParent) {
201 rv = mParent->AddChild(*this);
204 return rv;
207 bool
208 nsSMILTimeContainer::AddMilestone(const nsSMILMilestone& aMilestone,
209 mozilla::dom::SVGAnimationElement& aElement)
211 // We record the milestone time and store it along with the element but this
212 // time may change (e.g. if attributes are changed on the timed element in
213 // between samples). If this happens, then we may do an unecessary sample
214 // but that's pretty cheap.
215 return mMilestoneEntries.Push(MilestoneEntry(aMilestone, aElement));
218 void
219 nsSMILTimeContainer::ClearMilestones()
221 mMilestoneEntries.Clear();
224 bool
225 nsSMILTimeContainer::GetNextMilestoneInParentTime(
226 nsSMILMilestone& aNextMilestone) const
228 if (mMilestoneEntries.IsEmpty())
229 return false;
231 nsSMILTimeValue parentTime =
232 ContainerToParentTime(mMilestoneEntries.Top().mMilestone.mTime);
233 if (!parentTime.IsDefinite())
234 return false;
236 aNextMilestone = nsSMILMilestone(parentTime.GetMillis(),
237 mMilestoneEntries.Top().mMilestone.mIsEnd);
239 return true;
242 bool
243 nsSMILTimeContainer::PopMilestoneElementsAtMilestone(
244 const nsSMILMilestone& aMilestone,
245 AnimElemArray& aMatchedElements)
247 if (mMilestoneEntries.IsEmpty())
248 return false;
250 nsSMILTimeValue containerTime = ParentToContainerTime(aMilestone.mTime);
251 if (!containerTime.IsDefinite())
252 return false;
254 nsSMILMilestone containerMilestone(containerTime.GetMillis(),
255 aMilestone.mIsEnd);
257 NS_ABORT_IF_FALSE(mMilestoneEntries.Top().mMilestone >= containerMilestone,
258 "Trying to pop off earliest times but we have earlier ones that were "
259 "overlooked");
261 bool gotOne = false;
262 while (!mMilestoneEntries.IsEmpty() &&
263 mMilestoneEntries.Top().mMilestone == containerMilestone)
265 aMatchedElements.AppendElement(mMilestoneEntries.Pop().mTimebase);
266 gotOne = true;
269 return gotOne;
272 void
273 nsSMILTimeContainer::Traverse(nsCycleCollectionTraversalCallback* aCallback)
275 const MilestoneEntry* p = mMilestoneEntries.Elements();
276 while (p < mMilestoneEntries.Elements() + mMilestoneEntries.Length()) {
277 NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(*aCallback, "mTimebase");
278 aCallback->NoteXPCOMChild(static_cast<nsIContent*>(p->mTimebase.get()));
279 ++p;
283 void
284 nsSMILTimeContainer::Unlink()
286 mMilestoneEntries.Clear();
289 void
290 nsSMILTimeContainer::UpdateCurrentTime()
292 nsSMILTime now = IsPaused() ? mPauseStart : GetParentTime();
293 mCurrentTime = now - mParentOffset;
294 NS_ABORT_IF_FALSE(mCurrentTime >= 0, "Container has negative time");
297 void
298 nsSMILTimeContainer::NotifyTimeChange()
300 // Called when the container time is changed with respect to the document
301 // time. When this happens time dependencies in other time containers need to
302 // re-resolve their times because begin and end times are stored in container
303 // time.
305 // To get the list of timed elements with dependencies we simply re-use the
306 // milestone elements. This is because any timed element with dependents and
307 // with significant transitions yet to fire should have their next milestone
308 // registered. Other timed elements don't matter.
309 const MilestoneEntry* p = mMilestoneEntries.Elements();
310 #if DEBUG
311 uint32_t queueLength = mMilestoneEntries.Length();
312 #endif
313 while (p < mMilestoneEntries.Elements() + mMilestoneEntries.Length()) {
314 mozilla::dom::SVGAnimationElement* elem = p->mTimebase.get();
315 elem->TimedElement().HandleContainerTimeChange();
316 NS_ABORT_IF_FALSE(queueLength == mMilestoneEntries.Length(),
317 "Call to HandleContainerTimeChange resulted in a change to the "
318 "queue of milestones");
319 ++p;