GESTimelineObject

GESTimelineObject — Base Class for objects in a GESTimelineLayer

Synopsis

#include <ges/ges.h>

                    GESTimelineObject;
                    GESTimelineObjectClass;
GESTrackObject *    (*GESCreateTrackObjectFunc)         (GESTimelineObject *object,
                                                         GESTrack *track);
gboolean            (*GESCreateTrackObjectsFunc)        (GESTimelineObject *object,
                                                         GESTrack *track);
gboolean            (*GESFillTrackObjectFunc)           (GESTimelineObject *object,
                                                         GESTrackObject *trobject,
                                                         GstElement *gnlobj);
void                ges_timeline_object_set_inpoint     (GESTimelineObject *object,
                                                         guint64 inpoint);
void                ges_timeline_object_set_start       (GESTimelineObject *object,
                                                         guint64 start);
void                ges_timeline_object_set_duration    (GESTimelineObject *object,
                                                         guint64 duration);
GESTimelineLayer *  ges_timeline_object_get_layer       (GESTimelineObject *object);
GESTrackObject *    ges_timeline_object_find_track_object
                                                        (GESTimelineObject *object,
                                                         GESTrack *track,
                                                         GType type);
gboolean            ges_timeline_object_add_track_object
                                                        (GESTimelineObject *object,
                                                         GESTrackObject *trobj);

Object Hierarchy

  GObject
   +----GInitiallyUnowned
         +----GESTimelineObject
               +----GESTimelineSource
               +----GESTimelineOperation

Properties

  "duration"                 guint64               : Read / Write
  "height"                   guint                 : Read
  "in-point"                 guint64               : Read / Write
  "layer"                    GESTimelineLayer*     : Read
  "priority"                 guint                 : Read / Write
  "start"                    guint64               : Read / Write

Description

A GESTimelineObject is a 'natural' object which controls one or more GESTrackObject(s) in one or more GESTrack(s).

Keeps a reference to the GESTrackObject(s) it created and sets/updates their properties.

Details

GESTimelineObject

typedef struct _GESTimelineObject GESTimelineObject;

The GESTimelineObject base class.


GESTimelineObjectClass

typedef struct {
  GESCreateTrackObjectFunc create_track_object;
  GESCreateTrackObjectsFunc create_track_objects;

  /* FIXME : might need a release_track_object */
  GESFillTrackObjectFunc  fill_track_object;
  gboolean need_fill_track;
} GESTimelineObjectClass;

Subclasses can override the create_track_object and fill_track_object methods.

GESCreateTrackObjectFunc create_track_object;

method to create a single GESTrackObject for a given GESTrack.

GESCreateTrackObjectsFunc create_track_objects;

method to create multiple GESTrackObjects for a GESTrack.

GESFillTrackObjectFunc fill_track_object;

method to fill an associated GESTrackObject.

gboolean need_fill_track;

Set to TRUE if fill_track_object needs to be called.

GESCreateTrackObjectFunc ()

GESTrackObject *    (*GESCreateTrackObjectFunc)         (GESTimelineObject *object,
                                                         GESTrack *track);

Creates the 'primary' track object for this object.

Subclasses should implement this method if they only provide a single GESTrackObject per track.

If the subclass needs to create more than one GESTrackObject for a given track, then it should implement the 'create_track_objects' method instead.

The implementer of this function shall return the proper GESTrackObject that should be controlled by object for the given track.

The returned GESTrackObject will be automatically added to the list of objects controlled by the GESTimelineObject.

object :

a GESTimelineObject

track :

a GESTrack

Returns :

the GESTrackObject to be used, or NULL if it can't provide one for the given track.

GESCreateTrackObjectsFunc ()

gboolean            (*GESCreateTrackObjectsFunc)        (GESTimelineObject *object,
                                                         GESTrack *track);

Create all track objects this object handles for this type of track.

Subclasses should implement this method if they potentially need to return more than one GESTrackObject(s) for a given GESTrack.

For each object created, the subclass must call ges_timeline_object_add_track_object() with the newly created object and provided track.

object :

a GESTimelineObject

track :

a GESTrack

Returns :

TRUE on success FALSE on failure.

GESFillTrackObjectFunc ()

gboolean            (*GESFillTrackObjectFunc)           (GESTimelineObject *object,
                                                         GESTrackObject *trobject,
                                                         GstElement *gnlobj);

A function that will be called when the GNonLin object of a corresponding track object needs to be filled.

The implementer of this function shall add the proper GstElement to gnlobj using gst_bin_add().

object :

the GESTimelineObject controlling the track object

trobject :

the GESTrackObject

gnlobj :

the GNonLin object that needs to be filled.

Returns :

TRUE if the implementer succesfully filled the gnlobj, else FALSE.

ges_timeline_object_set_inpoint ()

void                ges_timeline_object_set_inpoint     (GESTimelineObject *object,
                                                         guint64 inpoint);

Set the in-point, that is the moment at which the object will start outputting data from its contents.

object :

a GESTimelineObject

inpoint :

the in-point in GstClockTime

ges_timeline_object_set_start ()

void                ges_timeline_object_set_start       (GESTimelineObject *object,
                                                         guint64 start);

Set the position of the object in its containing layer

object :

a GESTimelineObject

start :

the position in GstClockTime

ges_timeline_object_set_duration ()

void                ges_timeline_object_set_duration    (GESTimelineObject *object,
                                                         guint64 duration);

Set the duration of the object

object :

a GESTimelineObject

duration :

the duration in GstClockTime

ges_timeline_object_get_layer ()

GESTimelineLayer *  ges_timeline_object_get_layer       (GESTimelineObject *object);

Note: The reference count of the returned GESTimelineLayer will be increased, The user is responsible for unreffing it.

object :

a GESTimelineObject

Returns :

The GESTimelineLayer where this object is being used, NULL if it is not used on any layer. [transfer full]

ges_timeline_object_find_track_object ()

GESTrackObject *    ges_timeline_object_find_track_object
                                                        (GESTimelineObject *object,
                                                         GESTrack *track,
                                                         GType type);

Finds the GESTrackObject controlled by object that is used in track. You may optionally specify a GType to further narrow search criteria.

Note: The reference count of the returned GESTrackObject will be increased, unref when done with it.

object :

a GESTimelineObject

track :

a GESTrack or NULL

type :

a GType indicating the type of track object you are looking for or G_TYPE_NONE if you do not care about the track type.

Returns :

The GESTrackObject used by track, else NULL. [transfer full]

ges_timeline_object_add_track_object ()

gboolean            ges_timeline_object_add_track_object
                                                        (GESTimelineObject *object,
                                                         GESTrackObject *trobj);

Add a track object to the timeline object. Should only be called by subclasses implementing the create_track_objects (plural) vmethod.

Takes a reference on trobj.

object :

a GESTimelineObject

trobj :

the GESTrackObject

Returns :

TRUE on success, FALSE on failure.

Property Details

The "duration" property

  "duration"                 guint64               : Read / Write

The duration (in nanoseconds) which will be used in the container GESTrack starting from 'in-point'.

Default value: 18446744073709551615


The "height" property

  "height"                   guint                 : Read

The span of layer priorities which this object occupies.

Default value: 1


The "in-point" property

  "in-point"                 guint64               : Read / Write

The in-point at which this GESTimelineObject will start outputting data from its contents (in nanoseconds).

Ex : an in-point of 5 seconds means that the first outputted buffer will be the one located 5 seconds in the controlled resource.

Default value: 0


The "layer" property

  "layer"                    GESTimelineLayer*     : Read

The GESTimelineLayer where this object is being used.


The "priority" property

  "priority"                 guint                 : Read / Write

The layer priority of the timeline object.

Default value: 0


The "start" property

  "start"                    guint64               : Read / Write

The position of the object in the GESTimelineLayer (in nanoseconds).

Default value: 0