Property Target Easing Timeline interpolates a property gradually from its old value to a new value using an easing curve each time a new value is set to the property. More...

#include <kanzi/ui/node_component/animation/property_target_easing_timeline.hpp>

Inheritance diagram for kanzi::PropertyTargetEasingTimeline:

[legend]

Public Types
typedef function< float(float)>	EasingFunction

enum	InterpolationIfInterruptedMode { InterpolationIfInterruptedMode::StartFromCurrentInterpolatedValue, InterpolationIfInterruptedMode::StartFromCurrentTargetValue }

Public Types inherited from kanzi::Timeline
enum	DirectionBehavior { DirectionBehaviorNormal, DirectionBehaviorReverse, DirectionBehaviorPingPong }
	Specifies the direction behavior for a timeline. More...

Public Types inherited from kanzi::PropertyObject
typedef PropertyStorageContainer::const_iterator	PropertyStorageConstIterator

typedef vector< PropertyStoragePtr >	PropertyStorageContainer

typedef PropertyStorageContainer::iterator	PropertyStorageIterator

typedef intrusive_ptr< AbstractPropertyTypeDescriptor::PropertyStorage >	PropertyStoragePtr

typedef PropertyStorageContainer::reverse_iterator	PropertyStorageReverseIterator

Public Member Functions
EasingFunction	getEasingFunction () const
	Gets the easing function that defines the interpolation curve. More...

AnimationEasingMode	getEasingMode () const
	Gets the easing mode that defines how to apply the easing function to the interpolation. More...

PropertyField	getInterpolatedPropertyField () const
	Gets the property field whose value to interpolate. More...

AbstractPropertyType	getInterpolatedPropertyType () const
	Gets the property type whose value to interpolate. More...

chrono::milliseconds	getInterpolationDuration () const
	Gets the duration of the interpolation in milliseconds. More...

InterpolationIfInterruptedMode	getInterpolationIfInterruptedMode () const
	Gets the mode of handling the interpolation if it is interrupted. More...

string	getObjectPath () const
	Gets the path to the object whose property to interpolate. More...

void	setEasingFunction (EasingFunction easingFunction)
	Sets the easing function that defines the interpolation curve. More...

void	setEasingMode (AnimationEasingMode easingMode)
	Sets the easing mode that defines how to apply the easing function to the interpolation. More...

void	setInterpolationDuration (chrono::milliseconds interpolationDuration)
	Sets the duration of the interpolation in milliseconds. More...

void	setInterpolationIfInterruptedMode (InterpolationIfInterruptedMode mode)
	Sets the mode of handling the interpolation if it is interrupted. More...

Public Member Functions inherited from kanzi::Timeline
TimeInterval	calculateClipInterval ()
	Calculates clip interval of timeline. More...

optional< chrono::milliseconds >	calculateDuration ()
	Calculates the duration of the timeline. More...

unsigned int	calculateIterationCount ()
	Calculates number of iterations in timeline. More...

optional< chrono::milliseconds >	calculateIterationDuration ()
	Calculates iteration duration. More...

TimelinePlaybackSharedPtr	createPlayback (TimelinePlaybackContext &context)
	Creates playback for timeline. More...

optional< chrono::milliseconds >	getClipDuration () const
	Gets the clip duration of the timeline (in milliseconds). More...

chrono::milliseconds	getClipStartTime () const
	Gets the clip start time of the timeline (in milliseconds). More...

DirectionBehavior	getDirectionBehavior () const
	Gets the direction behavior of a timeline. More...

float	getDurationScale () const
	Gets the duration scale of timeline. More...

float	getMinimumDurationScale () const
	Gets minimum duration scale. More...

unsigned int	getRepeatCount () const
	Gets the repeat count of the timeline (zero indicates infinite repeats). More...

chrono::milliseconds	getStartTime () const
	Gets the start time of the timeline (in milliseconds). More...

void	setClipDuration (optional< chrono::milliseconds > duration)
	Sets the clip duration of the timeline (in milliseconds). More...

void	setClipStartTime (chrono::milliseconds clipStartTime)
	Sets the clip start time of the timeline (in milliseconds). More...

void	setDirectionBehavior (DirectionBehavior directionBehavior)
	Sets the direction behavior of a timeline. More...

void	setDurationScale (float scale)
	Sets the duration scale of timeline. More...

void	setRepeatCount (unsigned int repeatCount)
	Sets the repeat count of the timeline (zero indicates infinite repeats). More...

void	setStartTime (chrono::milliseconds startTime)
	Gets the start time of the timeline (in milliseconds). More...

Public Member Functions inherited from kanzi::Object
AppliedStyleEntrySharedPtr	applyObjectStyle (kanzi::StyleSharedPtr style)
	Applies a style to an object. More...

void	applyObjectStyles ()
	Apply all styles for an object node. More...

Domain *	getDomain () const
	Returns the domain the object belongs to. More...

const Metaclass *	getDynamicMetaclass () const override
	Returns the metaclass of the dynamic type of the object. More...

MainLoopScheduler *	getMainLoopScheduler () const
	Returns the MainLoopScheduler instance of the associated Domain. More...

detail::MessageDispatcher *	getMessageDispatcher () const
	Returns the message dispatcher of the object. More...

ResourceManager *	getResourceManager () const
	Returns the resource manager of the object. More...

ScriptingContextSharedPtr	getScriptingContext () const
	Gets the scripting context of the object. More...

	Object (Domain *domain)

void	setScriptingContext (ScriptingContextSharedPtr context)
	Sets the scripting context of the object. More...

void	unapplyObjectStyle (AppliedStyleEntrySharedPtr appliedStyleEntry)

void	unapplyObjectStyles ()
	Unapplies and removes all applied styles. More...

	~Object () override

Public Member Functions inherited from kanzi::MetaObject
bool	isTypeOf (const Metaclass *objectType) const
	Determines if the type of this object is the given type or derived from it. More...

virtual	~MetaObject ()

Public Member Functions inherited from kanzi::PropertyObject
template<typename DataType >
void	addPropertyModifier (const PropertyType< DataType > &propertyType, typename PropertyType< DataType >::Descriptor::ModifierCallback callback, void *owner)

template<typename DataType >
void	addPropertyNotificationHandler (const PropertyType< DataType > &propertyType, typename PropertyType< DataType >::Descriptor::NotificationCallback callback, void *owner)

template<typename DataType >
void	addPropertyValueSource (const PropertyType< DataType > &propertyType, typename PropertyType< DataType >::Descriptor::TypedValueSource valueSource, PropertyValuePrecedence precedence, void ownerPointer)

template<typename DataType >
void	addPropertyValueSource (const PropertyType< DataType > &propertyType, typename PropertyType< DataType >::Descriptor::TypedValueSource valueSource, PropertyValuePrecedence precedence, AbstractPropertyTypeDescriptor::ValueSourceOwner owner)

PropertyStorageContainer::iterator	beginPropertyStorage ()
	Returns the begin iterator to the internal property storage container. More...

PropertyStorageContainer::const_iterator	beginPropertyStorage () const
	Returns the begin iterator to the internal property storage container. More...

void	clearPropertyFlag (AbstractPropertyType propertyType, uint32_t flag)

void	copyLocalValue (const PropertyObject &other, AbstractPropertyType propertyType)
	Copies local value of single property from another object. More...

void	copyLocalValues (const PropertyObject &other)
	Copies all local values from another object. More...

PropertyStorageContainer::iterator	endPropertyStorage ()
	Returns the end iterator to the internal property storage container. More...

PropertyStorageContainer::const_iterator	endPropertyStorage () const
	Returns the end iterator to the internal property storage container. More...

template<typename DataType >
PropertyType< DataType >::Traits::ReturnType	getAbstractProperty (AbstractPropertyType abstractPropertyType) const

template<typename DataType >
PropertyType< DataType >::Traits::ReturnType	getAbstractPropertyBase (AbstractPropertyType abstractPropertyType) const

template<typename DataType >
optional< typename PropertyType< DataType >::Traits::ReturnType >	getOptionalAbstractProperty (AbstractPropertyType abstractPropertyType) const

template<typename DataType >
optional< typename PropertyType< DataType >::Traits::ReturnType >	getOptionalProperty (const PropertyType< DataType > &propertyType) const
	Evaluates the property value in the same way as the overload above but does not default to the value in property metadata if there are no inputs to the property value. More...

template<typename DataType >
optional< typename PropertyType< DataType >::Traits::ReturnType >	getOptionalPropertyBase (const PropertyType< DataType > &propertyType) const
	Returns the current value of a property disregarding modifiers, but does not default to the value in property metadata if there are no inputs to the property value. More...

template<typename DataType >
PropertyType< DataType >::Traits::ReturnType	getProperty (const PropertyType< DataType > &propertyType) const
	Returns the current value of a property type. More...

template<typename DataType >
PropertyType< DataType >::Traits::ReturnType	getPropertyBase (const PropertyType< DataType > &propertyType) const
	Returns the current value of a property disregarding modifiers. More...

template<typename DataType >
size_t	getPropertyNotificationHandlerCount (const PropertyType< DataType > &propertyType) const
	Gets number of current notification handlers for given property type. More...

bool	hasBaseValue (AbstractPropertyType propertyType) const
	Evaluates whether there are any inputs into the property value, disregarding modifiers. More...

bool	hasLocalValue (AbstractPropertyType propertyType) const
	Evaluates whether there is a local value set for the property. More...

bool	hasNonClassValue (AbstractPropertyType propertyType) const
	Evaluates whether there is a value of any precedence higher than class default value set for the property. More...

bool	hasValue (AbstractPropertyType propertyType) const
	Evaluates whether there are any inputs into the property value. More...

bool	isPropertyFlagSet (AbstractPropertyType propertyType, uint32_t flag) const

virtual void	onPropertyChanged (AbstractPropertyType propertyType, PropertyNotificationReason reason)
	Virtual function to handle property change notifications. More...

	PropertyObject ()

void	removeKzbProperties (flat_set< AbstractPropertyType > *keepProperties)
	Remove all KZB properties that are not included in a given set. More...

void	removeKzbProperties ()
	Remove all KZB properties. More...

template<typename DataType >
void	removeLocalPropertyValueSource (const PropertyType< DataType > &propertyType, typename PropertyType< DataType >::Descriptor::TypedValueSource valueSource, void ownerPointer)

void	removeLocalValue (AbstractPropertyType propertyType)
	Removes the local value associated with the property. More...

template<typename DataType >
void	removePropertyModifier (const PropertyType< DataType > &propertyType, typename PropertyType< DataType >::Descriptor::ModifierCallback callback, void *owner)

template<typename DataType >
void	removePropertyNotificationHandler (const PropertyType< DataType > &propertyType, typename PropertyType< DataType >::Descriptor::NotificationCallback callback, void *owner)

template<typename DataType >
void	removePropertyValueSource (const PropertyType< DataType > &propertyType, typename PropertyType< DataType >::Descriptor::TypedValueSource valueSource, void ownerPointer)

template<typename DataType >
void	setAbstractProperty (AbstractPropertyType abstractPropertyType, typename PropertyType< DataType >::Traits::ParameterType value)

template<typename DataType >
void	setProperty (const PropertyType< DataType > &propertyType, typename PropertyType< DataType >::Traits::ParameterType value)
	Sets the local value of a property type. More...

void	setPropertyFlag (AbstractPropertyType propertyType, uint32_t flag)

void	validatePropertyModifiers (AbstractPropertyType propertyType)

virtual	~PropertyObject ()

Static Public Member Functions
static PropertyTargetEasingTimelineSharedPtr	create (Domain *domain, string_view objectPath, AbstractPropertyType interpolatedPropertyType, PropertyField interpolatedPropertyField)
	Creates a Property Target Easing Timeline. More...

Static Public Member Functions inherited from kanzi::Object
static const Metaclass *	getStaticMetaclass ()
	Returns the metaclass of Object class. More...

static PropertyTypeEditorInfoSharedPtr	makeEditorInfo ()
	Default implementation that returns empty editor info. More...

Static Public Member Functions inherited from kanzi::MetaObject
static const Metaclass *	getStaticMetaclass ()
	Returns the metaclass of Object class. More...

static PropertyTypeEditorInfoSharedPtr	makeEditorInfo ()
	Default implementation that returns empty editor info. More...

Protected Member Functions
optional< chrono::milliseconds >	calculateContentDuration () override
	Timeline::calculateContentDuration() implementation. More...

TimelinePlaybackSharedPtr	createPlaybackOverride (TimelinePlaybackContext &context) override
	Timeline::createPlaybackOverride() implementation. More...

	PropertyTargetEasingTimeline (Domain *domain, string_view objectPath, AbstractPropertyType interpolatedPropertyType, PropertyField interpolatedPropertyField)
	Constructor. More...

Protected Member Functions inherited from kanzi::Timeline
virtual void	loadOverride (Domain *domain, string_view name, KzbFile &kzbFile, KzbMemoryParser &parser)
	Loads timeline data from KZB. More...

	Timeline (Domain *domain)
	Constructor. More...

Protected Member Functions inherited from kanzi::Object
void	initialize ()

void	onCopy (const Object &other)

Protected Member Functions inherited from kanzi::MetaObject
void	initialize ()

	MetaObject ()

Protected Member Functions inherited from kanzi::PropertyObject
AbstractPropertyTypeDescriptor::ValueSourceEntry *	acquireLocalValueSourceEntry (AbstractPropertyTypeDescriptor &descriptor, PropertyStoragePtr &propertyStorage)
	Acquires a local value source entry that is free for the assignment of a value. More...

AbstractPropertyTypeDescriptor::ModifierStorage *	acquireModifierStorage (AbstractPropertyTypeDescriptor &descriptor, AbstractPropertyTypeDescriptor::PropertyStorage &propertyStorage)

AbstractPropertyTypeDescriptor::NotificationStorage *	acquireNotificationStorage (AbstractPropertyTypeDescriptor &descriptor)

PropertyStoragePtr	acquirePropertyStorage (AbstractPropertyTypeDescriptor &descriptor)

void	addPropertyValueSource (AbstractPropertyTypeDescriptor &descriptor, AbstractPropertyTypeDescriptor::ValueSource valueSource, PropertyValuePrecedence precedence, void ownerPointer)
	Internally adds a property value source. More...

void	addPropertyValueSource (AbstractPropertyTypeDescriptor &descriptor, AbstractPropertyTypeDescriptor::ValueSource valueSource, PropertyValuePrecedence precedence, AbstractPropertyTypeDescriptor::ValueSourceOwner owner)
	Internally adds a property value source. More...

AbstractPropertyTypeDescriptor::ValueSourceEntry *	constructLocalValueSourceEntry (AbstractPropertyTypeDescriptor &descriptor, AbstractPropertyTypeDescriptor::PropertyStorage &propertyStorage)

PropertyStoragePtr	constructPropertyStorage (AbstractPropertyTypeDescriptor &descriptor)

void	copyLocalValue (const AbstractPropertyTypeDescriptor::PropertyStorage &otherPropertyStorage)
	Copy local value from property storage. More...

AbstractPropertyTypeDescriptor::ModifierStorage *	findModifierStorage (AbstractPropertyTypeDescriptor &descriptor)

AbstractPropertyTypeDescriptor::NotificationStorage *	findNotificationStorage (AbstractPropertyTypeDescriptor &descriptor) const

AbstractPropertyTypeDescriptor::PropertyStorage *	findPropertyStorage (AbstractPropertyTypeDescriptor &descriptor) const
	Gets the property storage for given property type descriptor. More...

PropertyStoragePtr	findPropertyStoragePtr (AbstractPropertyTypeDescriptor &descriptor) const
	Gets property storage intrusive pointer which you can use to hold a reference until the end of the operation. More...

AbstractPropertyTypeDescriptor *	findPropertyTypeDescriptorByNameAndDataType (string_view name, PropertyDataType dataType) const
	Finds a property type descriptor by name and data type. More...

AbstractPropertyTypeDescriptor *	findPropertyTypeDescriptorByQualifiedNameAndDataType (string_view qualifiedName, PropertyDataType dataType) const
	Like findPropertyTypeDescriptorByNameAndDataType, but only searches by matching with qualified names. More...

AbstractPropertyTypeDescriptor *	findPropertyTypeDescriptorByUnqualifiedNameAndDataType (string_view unqualifiedName, PropertyDataType dataType) const
	Like findPropertyTypeDescriptorByNameAndDataType, but only searches by matching with unqualified names. More...

AbstractPropertyTypeDescriptor::ValueSource *	getClassValueSource (AbstractPropertyTypeDescriptor &descriptor) const

AbstractPropertyTypeDescriptor::ValueSource *	getFinalValueSource (AbstractPropertyTypeDescriptor &descriptor) const

AbstractPropertyTypeDescriptor::ValueSource *	getNonClassValueSource (AbstractPropertyTypeDescriptor &descriptor) const

AbstractPropertyTypeDescriptor::ValueSource *	getTopValueSource (AbstractPropertyTypeDescriptor &descriptor) const
	Gets the top-level value source for a given property descriptor. More...

virtual void	notifyPropertyHandlers (PropertyStoragePtr &storagePtr, PropertyNotificationReason reason)
	Notifies all property handlers on a property storage. More...

void	onCopy (const PropertyObject &other)

void	removeLocalValue (AbstractPropertyTypeDescriptor &descriptor, PropertyStoragePtr &propertyStorage)
	Removes a local value from the given property storage. More...

void	removePropertyValueSource (AbstractPropertyTypeDescriptor &descriptor, AbstractPropertyTypeDescriptor::ValueSource valueSource, void owner)
	Removes a property value source. More...

void	validatePropertyModifiersAndNotifyHandlers (PropertyStoragePtr &propertyStorage)

Additional Inherited Members
Protected Types inherited from kanzi::Object
typedef vector< AppliedStyleEntrySharedPtr >	AppliedStyleContainer
	Applied style container. More...

Protected Attributes inherited from kanzi::Object
AppliedStyleContainer	m_appliedStyles
	Listing of applied styles applied to this object. More...

Detailed Description

Property Target Easing Timeline interpolates a property gradually from its old value to a new value using an easing curve each time a new value is set to the property.

The timeline interpolates a property of specified type on the object specified by its path.

Property Target Easing Timeline interpolates the property value using a from-to animation with an easing curve applied to it.

Note that setting time to playback of this timeline or advancing the timeline in reverse direction is not supported.

Examples

To create a property target easing timeline and set its target property and interpolation settings:

        // Create a property target easing timeline.
        auto timeline = PropertyTargetEasingTimeline::create(domain, ".", Node2D::OpacityProperty, PropertyFieldWhole);
        // Adjust easing interpolation settings.
        timeline->setInterpolationDuration(chrono::milliseconds(500));
        timeline->setEasingFunction(LinearEasingFunction());
        timeline->setEasingMode(AnimationEaseIn);

To create playback for property target easing timeline:

        // Create a context which resolves path to the node.
        SceneGraphTimelinePlaybackContext context(*node);
        // Create playback for property target easing timeline.
        auto playback = timeline->createPlayback(context);

To add playback of property target easing timeline to the clock:

        // Add playback to the clock. Once playback is added to the clock it starts
        // to interpolate its target property whenever the property changes.
        domain->getRootTimelineClock()->addTimelinePlayback(playback);

Member Typedef Documentation

◆ EasingFunction

typedef function<float(float)> kanzi::PropertyTargetEasingTimeline::EasingFunction

Member Enumeration Documentation

◆ InterpolationIfInterruptedMode

enum kanzi::PropertyTargetEasingTimeline::InterpolationIfInterruptedMode

strong

Enumerator
StartFromCurrentInterpolatedValue	When a new value is set to the target property before the interpolation to the previous value completes, the current value of the ongoing interpolation is used as the start value of the interpolation to the new target property value.
StartFromCurrentTargetValue	When a new value is set to the target property before the interpolation to the previous value completes, the target value of the ongoing interpolation is used as the start value of the interpolation to the new target property value.

Constructor & Destructor Documentation

◆ PropertyTargetEasingTimeline()

kanzi::PropertyTargetEasingTimeline::PropertyTargetEasingTimeline	(	Domain *	domain,
		string_view	objectPath,
		AbstractPropertyType	interpolatedPropertyType,
		PropertyField	interpolatedPropertyField
	)

explicitprotected

Constructor.

Parameters

domain	Domain.
objectPath	Path to the object whose property to interpolate.
interpolatedPropertyType	Property type whose value to interpolate.
interpolatedPropertyField	Field of the property to interpolate.

Member Function Documentation

◆ create()

static PropertyTargetEasingTimelineSharedPtr kanzi::PropertyTargetEasingTimeline::create	(	Domain *	domain,
		string_view	objectPath,
		AbstractPropertyType	interpolatedPropertyType,
		PropertyField	interpolatedPropertyField
	)

static

Creates a Property Target Easing Timeline.

Parameters

domain	Domain.
objectPath	Path to the object whose property to interpolate.
interpolatedPropertyType	Property type whose value to interpolate.
interpolatedPropertyField	Property field whose value to interpolate.

◆ getObjectPath()

string kanzi::PropertyTargetEasingTimeline::getObjectPath ( ) const

Gets the path to the object whose property to interpolate.

Returns: Object path.

◆ getInterpolatedPropertyType()

AbstractPropertyType kanzi::PropertyTargetEasingTimeline::getInterpolatedPropertyType ( ) const

Gets the property type whose value to interpolate.

Returns: Property type.

◆ getInterpolatedPropertyField()

PropertyField kanzi::PropertyTargetEasingTimeline::getInterpolatedPropertyField ( ) const

Gets the property field whose value to interpolate.

Returns: Property field.

◆ getInterpolationDuration()

chrono::milliseconds kanzi::PropertyTargetEasingTimeline::getInterpolationDuration ( ) const

Gets the duration of the interpolation in milliseconds.

Returns: Interpolation duration.

◆ setInterpolationDuration()

void kanzi::PropertyTargetEasingTimeline::setInterpolationDuration ( chrono::milliseconds interpolationDuration )

Sets the duration of the interpolation in milliseconds.

Parameters

interpolationDuration Interpolation duration.

◆ getEasingFunction()

EasingFunction kanzi::PropertyTargetEasingTimeline::getEasingFunction ( ) const

Gets the easing function that defines the interpolation curve.

Returns: Easing function.

◆ setEasingFunction()

void kanzi::PropertyTargetEasingTimeline::setEasingFunction ( EasingFunction easingFunction )

Sets the easing function that defines the interpolation curve.

Parameters

easingFunction Easing function.

◆ getEasingMode()

AnimationEasingMode kanzi::PropertyTargetEasingTimeline::getEasingMode ( ) const

Gets the easing mode that defines how to apply the easing function to the interpolation.

Returns: Easing mode.

◆ setEasingMode()

void kanzi::PropertyTargetEasingTimeline::setEasingMode ( AnimationEasingMode easingMode )

Sets the easing mode that defines how to apply the easing function to the interpolation.

Parameters

easingMode Easing mode.

◆ getInterpolationIfInterruptedMode()

InterpolationIfInterruptedMode kanzi::PropertyTargetEasingTimeline::getInterpolationIfInterruptedMode ( ) const

Gets the mode of handling the interpolation if it is interrupted.

Returns: Interpolation if interrupted mode.

◆ setInterpolationIfInterruptedMode()

void kanzi::PropertyTargetEasingTimeline::setInterpolationIfInterruptedMode ( InterpolationIfInterruptedMode mode )

Sets the mode of handling the interpolation if it is interrupted.

Parameters

mode	Interpolation if interrupted mode.

◆ createPlaybackOverride()

TimelinePlaybackSharedPtr kanzi::PropertyTargetEasingTimeline::createPlaybackOverride ( TimelinePlaybackContext & context )

overrideprotectedvirtual

Timeline::createPlaybackOverride() implementation.

Implements kanzi::Timeline.

◆ calculateContentDuration()

optional<chrono::milliseconds> kanzi::PropertyTargetEasingTimeline::calculateContentDuration ( )

overrideprotectedvirtual

Timeline::calculateContentDuration() implementation.

Reimplemented from kanzi::Timeline.

The documentation for this class was generated from the following file:

kanzi/ui/node_component/animation/property_target_easing_timeline.hpp

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Additional Inherited Members

Detailed Description

Examples

Member Typedef Documentation

◆ EasingFunction

Member Enumeration Documentation

◆ InterpolationIfInterruptedMode

Constructor & Destructor Documentation

◆ PropertyTargetEasingTimeline()

Member Function Documentation

◆ create()

◆ getObjectPath()

◆ getInterpolatedPropertyType()

◆ getInterpolatedPropertyField()

◆ getInterpolationDuration()

◆ setInterpolationDuration()

◆ getEasingFunction()

◆ setEasingFunction()

◆ getEasingMode()

◆ setEasingMode()

◆ getInterpolationIfInterruptedMode()

◆ setInterpolationIfInterruptedMode()

◆ createPlaybackOverride()

◆ calculateContentDuration()