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39
40#include "qtimeline.h"
41
42#include <private/qobject_p.h>
43#include <QtCore/qcoreevent.h>
44#include <QtCore/qmath.h>
45#include <QtCore/qelapsedtimer.h>
46
47QT_BEGIN_NAMESPACE
48
49class QTimeLinePrivate : public QObjectPrivate
50{
51 Q_DECLARE_PUBLIC(QTimeLine)
52public:
53 inline QTimeLinePrivate()
54 : easingCurve(QEasingCurve::InOutSine),
55 startTime(0), duration(1000), startFrame(0), endFrame(0),
56 updateInterval(1000 / 25),
57 totalLoopCount(1), currentLoopCount(0), currentTime(0), timerId(0),
58 direction(QTimeLine::Forward),
59 state(QTimeLine::NotRunning)
60 { }
61
62 QElapsedTimer timer;
63 QEasingCurve easingCurve;
64
65 int startTime;
66 int duration;
67 int startFrame;
68 int endFrame;
69 int updateInterval;
70 int totalLoopCount;
71 int currentLoopCount;
72
73 int currentTime;
74 int timerId;
75
76 QTimeLine::Direction direction;
77 QTimeLine::State state;
78 inline void setState(QTimeLine::State newState)
79 {
80 Q_Q(QTimeLine);
81 if (newState != state)
82 emit q->stateChanged(state = newState, QTimeLine::QPrivateSignal());
83 }
84
85 void setCurrentTime(int msecs);
86};
87
88/*!
89 \internal
90*/
91void QTimeLinePrivate::setCurrentTime(int msecs)
92{
93 Q_Q(QTimeLine);
94
95 qreal lastValue = q->currentValue();
96 int lastFrame = q->currentFrame();
97
98 // Determine if we are looping.
99 int elapsed = (direction == QTimeLine::Backward) ? (-msecs + duration) : msecs;
100 int loopCount = elapsed / duration;
101
102 bool looping = (loopCount != currentLoopCount);
103#ifdef QTIMELINE_DEBUG
104 qDebug() << "QTimeLinePrivate::setCurrentTime:" << msecs << duration << "with loopCount" << loopCount
105 << "currentLoopCount" << currentLoopCount
106 << "looping" << looping;
107#endif
108 if (looping)
109 currentLoopCount = loopCount;
110
111 // Normalize msecs to be between 0 and duration, inclusive.
112 currentTime = elapsed % duration;
113 if (direction == QTimeLine::Backward)
114 currentTime = duration - currentTime;
115
116 // Check if we have reached the end of loopcount.
117 bool finished = false;
118 if (totalLoopCount && currentLoopCount >= totalLoopCount) {
119 finished = true;
120 currentTime = (direction == QTimeLine::Backward) ? 0 : duration;
121 currentLoopCount = totalLoopCount - 1;
122 }
123
124 int currentFrame = q->frameForTime(currentTime);
125#ifdef QTIMELINE_DEBUG
126 qDebug() << "QTimeLinePrivate::setCurrentTime: frameForTime" << currentTime << currentFrame;
127#endif
128 if (!qFuzzyCompare(lastValue, q->currentValue()))
129 emit q->valueChanged(q->currentValue(), QTimeLine::QPrivateSignal());
130 if (lastFrame != currentFrame) {
131 const int transitionframe = (direction == QTimeLine::Forward ? endFrame : startFrame);
132 if (looping && !finished && transitionframe != currentFrame) {
133#ifdef QTIMELINE_DEBUG
134 qDebug("QTimeLinePrivate::setCurrentTime: transitionframe");
135#endif
136 emit q->frameChanged(transitionframe, QTimeLine::QPrivateSignal());
137 }
138#ifdef QTIMELINE_DEBUG
139 else {
140 QByteArray reason;
141 if (!looping)
142 reason += " not looping";
143 if (finished) {
144 if (!reason.isEmpty())
145 reason += " and";
146 reason += " finished";
147 }
148 if (transitionframe == currentFrame) {
149 if (!reason.isEmpty())
150 reason += " and";
151 reason += " transitionframe is equal to currentFrame: " + QByteArray::number(currentFrame);
152 }
153 qDebug("QTimeLinePrivate::setCurrentTime: not transitionframe because %s", reason.constData());
154 }
155#endif
156 emit q->frameChanged(currentFrame, QTimeLine::QPrivateSignal());
157 }
158 if (finished && state == QTimeLine::Running) {
159 q->stop();
160 emit q->finished(QTimeLine::QPrivateSignal());
161 }
162}
163
164/*!
165 \class QTimeLine
166 \inmodule QtCore
167 \brief The QTimeLine class provides a timeline for controlling animations.
168 \since 4.2
169 \ingroup animation
170
171 It's most commonly used to animate a GUI control by calling a slot
172 periodically. You can construct a timeline by passing its duration in
173 milliseconds to QTimeLine's constructor. The timeline's duration describes
174 for how long the animation will run. Then you set a suitable frame range
175 by calling setFrameRange(). Finally connect the frameChanged() signal to a
176 suitable slot in the widget you wish to animate (for example, \l {QProgressBar::}{setValue()}
177 in QProgressBar). When you proceed to calling start(), QTimeLine will enter
178 Running state, and start emitting frameChanged() at regular intervals,
179 causing your widget's connected property's value to grow from the lower
180 end to the upper and of your frame range, at a steady rate. You can
181 specify the update interval by calling setUpdateInterval(). When done,
182 QTimeLine enters NotRunning state, and emits finished().
183
184 Example:
185
186 \snippet code/src_corelib_tools_qtimeline.cpp 0
187
188 By default the timeline runs once, from the beginning and towards the end,
189 upon which you must call start() again to restart from the beginning. To
190 make the timeline loop, you can call setLoopCount(), passing the number of
191 times the timeline should run before finishing. The direction can also be
192 changed, causing the timeline to run backward, by calling
193 setDirection(). You can also pause and unpause the timeline while it's
194 running by calling setPaused(). For interactive control, the
195 setCurrentTime() function is provided, which sets the time position of the
196 time line directly. Although most useful in NotRunning state, (e.g.,
197 connected to a valueChanged() signal in a QSlider,) this function can be
198 called at any time.
199
200 The frame interface is useful for standard widgets, but QTimeLine can be
201 used to control any type of animation. The heart of QTimeLine lies in the
202 valueForTime() function, which generates a \e value between 0 and 1 for a
203 given time. This value is typically used to describe the steps of an
204 animation, where 0 is the first step of an animation, and 1 is the last
205 step. When running, QTimeLine generates values between 0 and 1 by calling
206 valueForTime() and emitting valueChanged(). By default, valueForTime()
207 applies an interpolation algorithm to generate these value. You can choose
208 from a set of predefined timeline algorithms by calling
209 setCurveShape().
210
211 Note that by default, QTimeLine uses the EaseInOut curve shape,
212 which provides a value that grows slowly, then grows steadily, and
213 finally grows slowly. For a custom timeline, you can reimplement
214 valueForTime(), in which case QTimeLine's curveShape property is ignored.
215
216 \sa QProgressBar, QProgressDialog
217*/
218
219/*!
220 \enum QTimeLine::State
221
222 This enum describes the state of the timeline.
223
224 \value NotRunning The timeline is not running. This is the initial state
225 of QTimeLine, and the state QTimeLine reenters when finished. The current
226 time, frame and value remain unchanged until either setCurrentTime() is
227 called, or the timeline is started by calling start().
228
229 \value Paused The timeline is paused (i.e., temporarily
230 suspended). Calling setPaused(false) will resume timeline activity.
231
232 \value Running The timeline is running. While control is in the event
233 loop, QTimeLine will update its current time at regular intervals,
234 emitting valueChanged() and frameChanged() when appropriate.
235
236 \sa state(), stateChanged()
237*/
238
239/*!
240 \enum QTimeLine::Direction
241
242 This enum describes the direction of the timeline when in \l Running state.
243
244 \value Forward The current time of the timeline increases with time (i.e.,
245 moves from 0 and towards the end / duration).
246
247 \value Backward The current time of the timeline decreases with time (i.e.,
248 moves from the end / duration and towards 0).
249
250 \sa setDirection()
251*/
252
253/*!
254 \enum QTimeLine::CurveShape
255
256 This enum describes the default shape of QTimeLine's value curve. The
257 default, shape is EaseInOutCurve. The curve defines the relation
258 between the value and the timeline.
259
260 \value EaseInCurve The value starts growing slowly, then increases in speed.
261 \value EaseOutCurve The value starts growing steadily, then ends slowly.
262 \value EaseInOutCurve The value starts growing slowly, then runs steadily, then grows slowly again.
263 \value LinearCurve The value grows linearly (e.g., if the duration is 1000 ms,
264 the value at time 500 ms is 0.5).
265 \value SineCurve The value grows sinusoidally.
266 \value CosineCurve The value grows cosinusoidally.
267
268 \sa setCurveShape()
269*/
270
271/*!
272 \fn void QTimeLine::valueChanged(qreal value)
273
274 QTimeLine emits this signal at regular intervals when in \l Running state,
275 but only if the current value changes. \a value is the current value. \a value is
276 a number between 0.0 and 1.0
277
278 \sa QTimeLine::setDuration(), QTimeLine::valueForTime(), QTimeLine::updateInterval
279*/
280
281/*!
282 \fn void QTimeLine::frameChanged(int frame)
283
284 QTimeLine emits this signal at regular intervals when in \l Running state,
285 but only if the current frame changes. \a frame is the current frame number.
286
287 \sa QTimeLine::setFrameRange(), QTimeLine::updateInterval
288*/
289
290/*!
291 \fn void QTimeLine::stateChanged(QTimeLine::State newState)
292
293 This signal is emitted whenever QTimeLine's state changes. The new state
294 is \a newState.
295*/
296
297/*!
298 \fn void QTimeLine::finished()
299
300 This signal is emitted when QTimeLine finishes (i.e., reaches the end of
301 its time line), and does not loop.
302*/
303
304/*!
305 Constructs a timeline with a duration of \a duration milliseconds. \a
306 parent is passed to QObject's constructor. The default duration is 1000
307 milliseconds.
308 */
309QTimeLine::QTimeLine(int duration, QObject *parent)
310 : QObject(*new QTimeLinePrivate, parent)
311{
312 setDuration(duration);
313}
314
315/*!
316 Destroys the timeline.
317 */
318QTimeLine::~QTimeLine()
319{
320 Q_D(QTimeLine);
321
322 if (d->state == Running)
323 stop();
324}
325
326/*!
327 Returns the state of the timeline.
328
329 \sa start(), setPaused(), stop()
330*/
331QTimeLine::State QTimeLine::state() const
332{
333 Q_D(const QTimeLine);
334 return d->state;
335}
336
337/*!
338 \property QTimeLine::loopCount
339 \brief the number of times the timeline should loop before it's finished.
340
341 A loop count of of 0 means that the timeline will loop forever.
342
343 By default, this property contains a value of 1.
344*/
345int QTimeLine::loopCount() const
346{
347 Q_D(const QTimeLine);
348 return d->totalLoopCount;
349}
350void QTimeLine::setLoopCount(int count)
351{
352 Q_D(QTimeLine);
353 d->totalLoopCount = count;
354}
355
356/*!
357 \property QTimeLine::direction
358 \brief the direction of the timeline when QTimeLine is in \l Running
359 state.
360
361 This direction indicates whether the time moves from 0 towards the
362 timeline duration, or from the value of the duration and towards 0 after
363 start() has been called.
364
365 By default, this property is set to \l Forward.
366*/
367QTimeLine::Direction QTimeLine::direction() const
368{
369 Q_D(const QTimeLine);
370 return d->direction;
371}
372void QTimeLine::setDirection(Direction direction)
373{
374 Q_D(QTimeLine);
375 d->direction = direction;
376 d->startTime = d->currentTime;
377 d->timer.start();
378}
379
380/*!
381 \property QTimeLine::duration
382 \brief the total duration of the timeline in milliseconds.
383
384 By default, this value is 1000 (i.e., 1 second), but you can change this
385 by either passing a duration to QTimeLine's constructor, or by calling
386 setDuration(). The duration must be larger than 0.
387
388 \note Changing the duration does not cause the current time to be reset
389 to zero or the new duration. You also need to call setCurrentTime() with
390 the desired value.
391*/
392int QTimeLine::duration() const
393{
394 Q_D(const QTimeLine);
395 return d->duration;
396}
397void QTimeLine::setDuration(int duration)
398{
399 Q_D(QTimeLine);
400 if (duration <= 0) {
401 qWarning("QTimeLine::setDuration: cannot set duration <= 0");
402 return;
403 }
404 d->duration = duration;
405}
406
407/*!
408 Returns the start frame, which is the frame corresponding to the start of
409 the timeline (i.e., the frame for which the current value is 0).
410
411 \sa setStartFrame(), setFrameRange()
412*/
413int QTimeLine::startFrame() const
414{
415 Q_D(const QTimeLine);
416 return d->startFrame;
417}
418
419/*!
420 Sets the start frame, which is the frame corresponding to the start of the
421 timeline (i.e., the frame for which the current value is 0), to \a frame.
422
423 \sa startFrame(), endFrame(), setFrameRange()
424*/
425void QTimeLine::setStartFrame(int frame)
426{
427 Q_D(QTimeLine);
428 d->startFrame = frame;
429}
430
431/*!
432 Returns the end frame, which is the frame corresponding to the end of the
433 timeline (i.e., the frame for which the current value is 1).
434
435 \sa setEndFrame(), setFrameRange()
436*/
437int QTimeLine::endFrame() const
438{
439 Q_D(const QTimeLine);
440 return d->endFrame;
441}
442
443/*!
444 Sets the end frame, which is the frame corresponding to the end of the
445 timeline (i.e., the frame for which the current value is 1), to \a frame.
446
447 \sa endFrame(), startFrame(), setFrameRange()
448*/
449void QTimeLine::setEndFrame(int frame)
450{
451 Q_D(QTimeLine);
452 d->endFrame = frame;
453}
454
455/*!
456 Sets the timeline's frame counter to start at \a startFrame, and end and
457 \a endFrame. For each time value, QTimeLine will find the corresponding
458 frame when you call currentFrame() or frameForTime() by interpolating,
459 using the return value of valueForTime().
460
461 When in Running state, QTimeLine also emits the frameChanged() signal when
462 the frame changes.
463
464 \sa startFrame(), endFrame(), start(), currentFrame()
465*/
466void QTimeLine::setFrameRange(int startFrame, int endFrame)
467{
468 Q_D(QTimeLine);
469 d->startFrame = startFrame;
470 d->endFrame = endFrame;
471}
472
473/*!
474 \property QTimeLine::updateInterval
475 \brief the time in milliseconds between each time QTimeLine updates its
476 current time.
477
478 When updating the current time, QTimeLine will emit valueChanged() if the
479 current value changed, and frameChanged() if the frame changed.
480
481 By default, the interval is 40 ms, which corresponds to a rate of 25
482 updates per second.
483*/
484int QTimeLine::updateInterval() const
485{
486 Q_D(const QTimeLine);
487 return d->updateInterval;
488}
489void QTimeLine::setUpdateInterval(int interval)
490{
491 Q_D(QTimeLine);
492 d->updateInterval = interval;
493}
494
495/*!
496 \property QTimeLine::curveShape
497 \brief the shape of the timeline curve.
498
499 The curve shape describes the relation between the time and value for the
500 base implementation of valueForTime().
501
502 If you have reimplemented valueForTime(), this value is ignored.
503
504 By default, this property is set to \l EaseInOutCurve.
505
506 \sa valueForTime()
507*/
508QTimeLine::CurveShape QTimeLine::curveShape() const
509{
510 Q_D(const QTimeLine);
511 switch (d->easingCurve.type()) {
512 default:
513 case QEasingCurve::InOutSine:
514 return EaseInOutCurve;
515 case QEasingCurve::InCurve:
516 return EaseInCurve;
517 case QEasingCurve::OutCurve:
518 return EaseOutCurve;
519 case QEasingCurve::Linear:
520 return LinearCurve;
521 case QEasingCurve::SineCurve:
522 return SineCurve;
523 case QEasingCurve::CosineCurve:
524 return CosineCurve;
525 }
526 return EaseInOutCurve;
527}
528
529static QEasingCurve::Type convert(QTimeLine::CurveShape shape)
530{
531 switch (shape) {
532#define CASE(x, y) case QTimeLine::x: return QEasingCurve::y
533 CASE(EaseInOutCurve, InOutSine);
534 CASE(EaseInCurve, InCurve);
535 CASE(EaseOutCurve, OutCurve);
536 CASE(LinearCurve, Linear);
537 CASE(SineCurve, SineCurve);
538 CASE(CosineCurve, CosineCurve);
539#undef CASE
540 }
541 Q_UNREACHABLE();
542}
543
544void QTimeLine::setCurveShape(CurveShape shape)
545{
546 setEasingCurve(convert(shape));
547}
548
549/*!
550 \property QTimeLine::easingCurve
551
552 \since 4.6
553
554 Specifies the easing curve that the timeline will use.
555 If both easing curve and curveShape are set, the last set property will
556 override the previous one. (If valueForTime() is reimplemented it will
557 override both)
558*/
559
560QEasingCurve QTimeLine::easingCurve() const
561{
562 Q_D(const QTimeLine);
563 return d->easingCurve;
564}
565
566void QTimeLine::setEasingCurve(const QEasingCurve& curve)
567{
568 Q_D(QTimeLine);
569 d->easingCurve = curve;
570}
571
572/*!
573 \property QTimeLine::currentTime
574 \brief the current time of the time line.
575
576 When QTimeLine is in Running state, this value is updated continuously as
577 a function of the duration and direction of the timeline. Otherwise, it is
578 value that was current when stop() was called last, or the value set by
579 setCurrentTime().
580
581 By default, this property contains a value of 0.
582*/
583int QTimeLine::currentTime() const
584{
585 Q_D(const QTimeLine);
586 return d->currentTime;
587}
588void QTimeLine::setCurrentTime(int msec)
589{
590 Q_D(QTimeLine);
591 d->startTime = 0;
592 d->currentLoopCount = 0;
593 d->timer.restart();
594 d->setCurrentTime(msec);
595}
596
597/*!
598 Returns the frame corresponding to the current time.
599
600 \sa currentTime(), frameForTime(), setFrameRange()
601*/
602int QTimeLine::currentFrame() const
603{
604 Q_D(const QTimeLine);
605 return frameForTime(d->currentTime);
606}
607
608/*!
609 Returns the value corresponding to the current time.
610
611 \sa valueForTime(), currentFrame()
612*/
613qreal QTimeLine::currentValue() const
614{
615 Q_D(const QTimeLine);
616 return valueForTime(d->currentTime);
617}
618
619/*!
620 Returns the frame corresponding to the time \a msec. This value is
621 calculated using a linear interpolation of the start and end frame, based
622 on the value returned by valueForTime().
623
624 \sa valueForTime(), setFrameRange()
625*/
626int QTimeLine::frameForTime(int msec) const
627{
628 Q_D(const QTimeLine);
629 if (d->direction == Forward)
630 return d->startFrame + int((d->endFrame - d->startFrame) * valueForTime(msec));
631 return d->startFrame + qCeil((d->endFrame - d->startFrame) * valueForTime(msec));
632}
633
634/*!
635 Returns the timeline value for the time \a msec. The returned value, which
636 varies depending on the curve shape, is always between 0 and 1. If \a msec
637 is 0, the default implementation always returns 0.
638
639 Reimplement this function to provide a custom curve shape for your
640 timeline.
641
642 \sa CurveShape, frameForTime()
643*/
644qreal QTimeLine::valueForTime(int msec) const
645{
646 Q_D(const QTimeLine);
647 msec = qMin(qMax(msec, 0), d->duration);
648
649 qreal value = msec / qreal(d->duration);
650 return d->easingCurve.valueForProgress(value);
651}
652
653/*!
654 Starts the timeline. QTimeLine will enter Running state, and once it
655 enters the event loop, it will update its current time, frame and value at
656 regular intervals. The default interval is 40 ms (i.e., 25 times per
657 second). You can change the update interval by calling
658 setUpdateInterval().
659
660 The timeline will start from position 0, or the end if going backward.
661 If you want to resume a stopped timeline without restarting, you can call
662 resume() instead.
663
664 \sa resume(), updateInterval(), frameChanged(), valueChanged()
665*/
666void QTimeLine::start()
667{
668 Q_D(QTimeLine);
669 if (d->timerId) {
670 qWarning("QTimeLine::start: already running");
671 return;
672 }
673 int curTime = 0;
674 if (d->direction == Backward)
675 curTime = d->duration;
676 d->timerId = startTimer(d->updateInterval);
677 d->startTime = curTime;
678 d->currentLoopCount = 0;
679 d->timer.start();
680 d->setState(Running);
681 d->setCurrentTime(curTime);
682}
683
684/*!
685 Resumes the timeline from the current time. QTimeLine will reenter Running
686 state, and once it enters the event loop, it will update its current time,
687 frame and value at regular intervals.
688
689 In contrast to start(), this function does not restart the timeline before
690 it resumes.
691
692 \sa start(), updateInterval(), frameChanged(), valueChanged()
693*/
694void QTimeLine::resume()
695{
696 Q_D(QTimeLine);
697 if (d->timerId) {
698 qWarning("QTimeLine::resume: already running");
699 return;
700 }
701 d->timerId = startTimer(d->updateInterval);
702 d->startTime = d->currentTime;
703 d->timer.start();
704 d->setState(Running);
705}
706
707/*!
708 Stops the timeline, causing QTimeLine to enter NotRunning state.
709
710 \sa start()
711*/
712void QTimeLine::stop()
713{
714 Q_D(QTimeLine);
715 if (d->timerId)
716 killTimer(d->timerId);
717 d->setState(NotRunning);
718 d->timerId = 0;
719}
720
721/*!
722 If \a paused is true, the timeline is paused, causing QTimeLine to enter
723 Paused state. No updates will be signaled until either start() or
724 setPaused(false) is called. If \a paused is false, the timeline is resumed
725 and continues where it left.
726
727 \sa state(), start()
728*/
729void QTimeLine::setPaused(bool paused)
730{
731 Q_D(QTimeLine);
732 if (d->state == NotRunning) {
733 qWarning("QTimeLine::setPaused: Not running");
734 return;
735 }
736 if (paused && d->state != Paused) {
737 d->startTime = d->currentTime;
738 killTimer(d->timerId);
739 d->timerId = 0;
740 d->setState(Paused);
741 } else if (!paused && d->state == Paused) {
742 // Same as resume()
743 d->timerId = startTimer(d->updateInterval);
744 d->startTime = d->currentTime;
745 d->timer.start();
746 d->setState(Running);
747 }
748}
749
750/*!
751 Toggles the direction of the timeline. If the direction was Forward, it
752 becomes Backward, and vice verca.
753
754 \sa setDirection()
755*/
756void QTimeLine::toggleDirection()
757{
758 Q_D(QTimeLine);
759 setDirection(d->direction == Forward ? Backward : Forward);
760}
761
762/*!
763 \reimp
764*/
765void QTimeLine::timerEvent(QTimerEvent *event)
766{
767 Q_D(QTimeLine);
768 if (event->timerId() != d->timerId) {
769 event->ignore();
770 return;
771 }
772 event->accept();
773
774 if (d->direction == Forward) {
775 d->setCurrentTime(d->startTime + d->timer.elapsed());
776 } else {
777 d->setCurrentTime(d->startTime - d->timer.elapsed());
778 }
779}
780
781QT_END_NAMESPACE
782
783#include "moc_qtimeline.cpp"
784