class "multitrack". More...

#include <liblives.hpp>

Public Member Functions
bool	isValid () const
	returns whether the multitrack is valid or not. More...

bool	isActive () const
	returns whether the multitrack is active or not. More...

bool	setCurrentTrack (int track) const
	Set the current track if isActive() is true. More...

int	currentTrack () const
	If isActive() is true, then this method returns the current active track. More...

double	setCurrentTime (double time) const
	Set the current playback start time in seconds. More...

double	currentTime () const
	Return the current playback time in seconds. More...

livesString	trackLabel (int track) const
	If isActive() is true, then this method returns the label for a track. More...

bool	setTrackLabel (int track, livesString label=livesString()) const
	Set the label for a track. More...

lives_gravity_t	gravity () const
	Returns the value of the multitrack gravity. More...

lives_gravity_t	setGravity (lives_gravity_t mode) const
	Set the gravity mode for multitrack. More...

lives_insert_mode_t	insertMode () const
	Returns the value of the multitrack insert mode. More...

lives_insert_mode_t	setInsertMode (lives_insert_mode_t mode) const
	Set the gravity mode for multitrack. More...

int	addVideoTrack (bool in_front) const
	Append a new video track into the timeline. More...

int	numVideoTracks () const
	Returns the number of video tracks for multitrack. More...

int	numAudioTracks () const
	Returns the number of audio backing tracks for multitrack. More...

double	FPS () const
	Return the framerate of the multitrack in frames per second. More...

block	insertBlock (clip c, bool ignore_selection_limits=false, bool without_audio=false) const
	Insert frames from clip c into currentTrack() at currentTime() If ignore_selection_limits is true, then all frames from the clip will be inserted, otherwise (the default) only frames from clip::selectionStart() to clip::selectionEnd() will be used. More...

livesString	wipeLayout (bool force=false) const
	Wipe the current layout, leaving a blank layout. More...

livesString	chooseLayout () const
	Allow the user to graphically choose a layout to load for the set. More...

livesStringList	availableLayouts () const
	Return a list of the available layouts for the currently loaded set. More...

bool	reloadLayout (livesString filename) const
	Reload the selected layout, replacing the current multitrack layout. More...

livesString	saveLayout (livesString name) const
	Save the current layout using the name supplied. More...

livesString	saveLayout () const
	Save the current layout using the current layout name. More...

clip	render (bool render_audio=true, bool normalise_audio=true) const
	Render the current layout to a new clip and return it. More...

effect	autoTransition () const
	Returns the current autotransition effect for multitrack mode. More...

bool	disableAutoTransition () const
	Set the current autotransition effect for multitrack mode to "None" (no effect). More...

bool	setAutoTransition (effect autotrans) const
	Set the current autotransition effect for multitrack mode. More...

bool	operator== (const multitrack &other) const

Protected Member Functions
	multitrack (livesApp *lives=NULL)
	multitrack

Protected Attributes
livesApp *	m_lives
	The linked LiVES application.

Detailed Description

class "multitrack".

Represents the multitrack object in a livesApp.

Member Function Documentation

int lives::multitrack::addVideoTrack ( bool in_front ) const

Append a new video track into the timeline.

Only works if isActive() is true, and livesApp::status() is LIVES_STATUS_READY.

Parameters

in_front set to true to insert a video track in front of existing video tracks. Otherwise insert will be behind.

Returns: the index number of the newly added track, or -1 if the operation failed.

effect lives::multitrack::autoTransition ( ) const

Returns the current autotransition effect for multitrack mode.

If no effect is set, returns an invalid effect. If the owning livesApp::isInvalid() is true, or if livesApp::Status() is LIVES_STATUS_NOTREADY, returns an invalid effect.

Returns: the autotransition effect for multitrack.

See Also: setAutoTransition().; disableAutoTransition().

livesStringList lives::multitrack::availableLayouts ( ) const

Return a list of the available layouts for the currently loaded set.

If livesApp::isReady() is false, or if no set is loaded, then an empty livesStringList is returned.

Returns: list of available layouts for the currently loaded set

See Also: reloadLayout().

livesString lives::multitrack::chooseLayout ( ) const

Allow the user to graphically choose a layout to load for the set.

Only works if livesApp::status() is LIVES_STATUS_READY and isActive() is true, otherwise an empty livesString is returned.

Returns: the name of the layout selected.

See Also: reloadLayout().; availableLayouts().

double lives::multitrack::currentTime ( ) const

Return the current playback time in seconds.

If isActive() is true this returns the current player time in the multitrack timeline (equivalent to to player::playbackTime(), and during playback, equivalent to player::elapsedTime() plus a constant offset). This function works when livesApp::status() is LIVE_STATUS_READY or LIVES_STATUS_PLAYING. If isActive() is false, 0. is returned.

Returns: the current clip playback time.

See Also: setCurrentTime().; currentAudioTime().; elapsedTime().

int lives::multitrack::currentTrack ( ) const

If isActive() is true, then this method returns the current active track.

The active track defines the insertion point for video and audio, along with the currentTime(). If isActive() is false, or the livesApp::status is not LIVES_STATUS_READY or LIVES_STATUS_PLAYING then the return value is undefined.

Returns: the current active track in multitrack mode. A value >= 0 represents a video track, a value < 0 represents a backing audio track.

See Also: setCurrentTrack().

bool lives::multitrack::disableAutoTransition ( ) const

Set the current autotransition effect for multitrack mode to "None" (no effect).

If the livesApp::status() is not LIVES_STATUS_READY or LIVES_STATUS_PLAYING, returns false and nothing happens.

Returns: true if the autotransition was disabled.

See Also: autoTransition().; setAutoTransition().

double lives::multitrack::FPS ( ) const

Return the framerate of the multitrack in frames per second.

If isActive() is false, returns 0. Otherwise when the livesAPP::status() is LIVES_STATUS_PLAYING, player::FPS() takes this value.

Returns: the framerate of the multitrack in frames per second.

lives_gravity_t lives::multitrack::gravity ( ) const

Returns the value of the multitrack gravity.

This value, together with the insertMode() defines what happens when a block is inserted, moved or deleted. If isActive() is false, the return value is undefined.

Returns: the multitrack gravity.

See Also: insertMode().

block lives::multitrack::insertBlock	(	clip	c,
		bool	ignore_selection_limits = `false`,
		bool	without_audio = `false`
	)		const

Insert frames from clip c into currentTrack() at currentTime() If ignore_selection_limits is true, then all frames from the clip will be inserted, otherwise (the default) only frames from clip::selectionStart() to clip::selectionEnd() will be used.

If without_audio is false (the default), audio is also inserted. Frames are automatically resampled to fit layout::fps(). Depending on the insertMode(), it may not be possible to do the insertion. In case of failure an invalid block is returned. If the current track is a backing audio track, then only audio is inserted; in this case if without_audio is true an invalid block is returned. Only works if livesApp::status() is LIVES_STATUS_READY and isActive() is true. Note: the actual place where the block ends up, and its final size depends on various factors such as the gravity() setting, the insertMode() setting, and the location of other blocks in the layout. The insertion may cause other blocks to relocate.

Parameters

c	the clip to insert from
ignore_selection_limits	if true then all frames from the clip will be inserted
without_audio	if false then audio is also inserted

Returns: the newly inserted block.

See Also: setCurrentTrack().; setCurrentTime().; clip::setSelectionStart().; clip::setSelectionEnd().; setGravity().; block::remove().

lives_insert_mode_t lives::multitrack::insertMode ( ) const

Returns the value of the multitrack insert mode.

This value, together with gravity() defines what happens when a block is inserted, moved or deleted. If isActive() is false, the return value is undefined.

Returns: the multitrack insert mode.

See Also: gravity().

bool lives::multitrack::isActive ( ) const

returns whether the multitrack is active or not.

This is equivent to livesApp::mode() == LIVES_INTERFACE_MODE_MULTITRACK.

Returns: whether the multitrack is active or not.

bool lives::multitrack::isValid ( ) const

returns whether the multitrack is valid or not.

A valid multitrack is one which is owned by a valid livesApp, whose livesApp::status() is not LIVES_STATUS_NOTREADY.

Returns: whether the multitrack is valid

int lives::multitrack::numAudioTracks ( ) const

Returns the number of audio backing tracks for multitrack.

If isActive() is false, 0 is returned.

Returns: the number of audio tracks

int lives::multitrack::numVideoTracks ( ) const

Returns the number of video tracks for multitrack.

If isActive() is false, 0 is returned.

Returns: the number of video tracks

See Also: addVideoTrack()

bool lives::multitrack::operator== ( const multitrack & other ) const

inline

Returns: true if the two layouts have the same livesApp owner

bool lives::multitrack::reloadLayout ( livesString filename ) const

Reload the selected layout, replacing the current multitrack layout.

Only works if livesApp::status() is LIVES_STATUS_READY and isActive() is true. The layout must be "owned" by the currently loaded set, otherwise an error may be shown and it will not be loaded. If filename is an empty livesString, chooseLayout() will be called first to get the layout name. If livesApp::interactive() is true, the user will have a chance to save the current layout (if any) first.

Parameters

filename the filename of the layout to load

Returns: true if the specified layout could be loaded

See Also: chooseLayout().; availableLayouts().; saveLayout().

clip lives::multitrack::render	(	bool	render_audio = `true`,
		bool	normalise_audio = `true`
	)		const

Render the current layout to a new clip and return it.

Only works if isActive() is true, and livesApp::status() is LIVES_STATUS_READY, and the current layout is not empty. If livesApp::interactive() is true, the user may choose to cancel the operation, or to render fewer than all frames. After rendering, if prefs::mtExitRender() is true, the livesApp::mode() will change to LIVES_INTERFACE_MODE_CLIPEDIT, and isActive() will change to false.

Parameters

render_audio	true if audio should be rendered in addition to video.
normalise_audio	if true then the audio volume is normalized (backing audio gets half volume, video tracks get half volume)

Returns: clip a new clip which contains the rendered video, or an invalid clip in case of failure.

livesString lives::multitrack::saveLayout ( livesString name ) const

Save the current layout using the name supplied.

The layout will be saved in the layouts directory for the currently loaded set, so the name should not include any directory component. Only works if the livesApp::status() is LIVES_STATUS_READY, and the current layout is not empty, otherwise an empty livesString is returned. Note that this WILL work even if isActive() is false. If livesApp::interactive() is true, the user may choose to cancel the operation. If the layout name is empty, the user will be prompted graphically to enter a name. If the set name is empty, the user will be prompted to enter a set name (if livesApp::interactive() is true; otherwise this will fail and an empty string will be returned). Rarely it will not be possible to save a layout (if it was generated by recording events, and it contains generated audio or video).

Parameters

name	the name to save the layout

Returns: the filename the set was saved to, or empty livesString if saving failed.

See Also: wipeLayout().; reloadLayout();; set::setName().

livesString lives::multitrack::saveLayout ( ) const

Save the current layout using the current layout name.

Only works if the livesApp::status() is LIVES_STATUS_READY, and the current layout is not empty, otherwise an empty livesString is returned. Note that this WILL work even if isActive() is false. If livesApp::interactive() is true, the user may choose to cancel the operation. If the layout name has not been previously set, the user will be prompted graphically to enter a name. If the set name is empty, the user will be prompted to enter a set name (if livesApp::interactive() is true; otherwise this will fail and an empty string will be returned). Rarely it will not be possible to save a layout (if it was generated by recording events, and it contains generated audio or video).

Returns: the filename the set was saved to, or empty livesString if saving failed.

See Also: wipeLayout().; reloadLayout();; set::setName().

bool lives::multitrack::setAutoTransition ( effect autotrans ) const

Set the current autotransition effect for multitrack mode.

If the livesApp::status() is not LIVES_STATUS_READY or LIVES_STATUS_PLAYING, returns false and nothing happens. If the effect is not a transition, false is returned and nothing happens. If the effect is invalid, this is the same as calling disableAutoTransition().

Parameters

autotrans the new autotransition effect for multitrack.

Returns: true if the autotransition was changed.

See Also: autoTransition().; disableAutoTransition().

double lives::multitrack::setCurrentTime ( double time ) const

Set the current playback start time in seconds.

This is also the insertion point for insertBlock(). Only works if the livesApp::status() is LIVES_STATUS_READY and isActive() is true. Setting the current time may cause the timeline to stretch visually (i.e zoom out). The miminum value is 0.0; values < 0.0 will be ignored. This function is synonymous with player::setPlaybackTime().

Parameters

time	the time in seconds to set playback start time to.

Returns: the new playback start time.

See Also: currentTime().

bool lives::multitrack::setCurrentTrack ( int track ) const

Set the current track if isActive() is true.

Only works when livesApp::status() is LIVES_STATUS_READY or LIVES_STATUS_PLAYING.

Parameters

track a value >= 0 represents a video track, a value < 0 represents a backing audio track.

Returns: true if the track setting was successful.

See Also: currentTrack().

lives_gravity_t lives::multitrack::setGravity ( lives_gravity_t mode ) const

Set the gravity mode for multitrack.

If isActive() is false, nothing happens and an undefined value is returned, otherwise if livesApp::status() is not LIVES_STATUS_READY or LIVES_STATUS_PLAYING, nothing happens.

Parameters

mode	the new gravity mode to set.

Returns: the new gravity mode.

See Also: gravity().

lives_insert_mode_t lives::multitrack::setInsertMode ( lives_insert_mode_t mode ) const

Set the gravity mode for multitrack.

If isActive() is false, nothing happens and an undefined value is returned, otherwise if livesApp::status() is not LIVES_STATUS_READY or LIVES_STATUS_PLAYING, nothing happens.

Parameters

mode	the new insert mode to set.

Returns: the new insert mode.

See Also: insertMode().

bool lives::multitrack::setTrackLabel	(	int	track,
		livesString	label = `livesString()`
	)		const

Set the label for a track.

This is for display purposes only and has no other effect. If isActive() is false, the track label is not changed, and false is returned. If the label is not provided, or is an empty livesString, the user will be prompted to enter a name at runtime.

Parameters

track	the track number. Must be >= 0.
label	a livesString containing the text to label the track with.

Returns: true if it was possible to change the label.

See Also: trackLabel().

livesString lives::multitrack::trackLabel ( int track ) const

If isActive() is true, then this method returns the label for a track.

Parameters

track the track number. A value >= 0 represents a video track, a value < 0 represents a backing audio track.

Returns: the track label, or empty livesString if the specified track does not exist.

See Also: setTrackLabel().

livesString lives::multitrack::wipeLayout ( bool force = false ) const

Wipe the current layout, leaving a blank layout.

If force is false, then the user will have a chance to cancel (if livesApp::interactive() is true), or to save the layout. Only works if livesApp::status() is LIVES_STATUS_READY and isActive() is true. Otherwise, the layout will not be wiped, and an empty livesString will be returned.

Parameters

force set to true to force the layout to be wiped.

Returns: the name which the layout was saved to, or empty livesString if it was not saved.

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

src/liblives.hpp
src/liblives.cpp

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Member Function Documentation