gstreamer/ges/ges-clip.h
Henry Wilkes 269c2d1dc0 timeline: re-handle clip children track selection
The way a clip's track elements are added to tracks was re-handled. This
doesn't affect the normal usage of a simple audio-video timeline, where
the tracks are added before any clips, but usage for multi-track
timelines has improved. The main changes are:

+ We can now handle a track being selected for more than one track,
  including a full copy of their children properties and bindings.
  (Previously broken.)
+ When a clip is split, we copy the new elements directly into the same
  track, avoiding select-tracks-for-object.
+ When a clip is grouped or ungrouped, we avoid moving the elements to
  or from tracks.
+ Added API to allow users to copy the core elements of a clip directly
  into a track, complementing select-tracks-for-object.
+ Enforced the rule that a clip can only contain one core child in a
  track, and all the non-core children must be added to tracks that
  already contains a core child. This extends the previous condition
  that two sources from the same clip should not be added to the same
  track.
+ Made ges_track_add_element check that the newly added track element
  does not break the configuration rules of the timeline.
+ When adding a track to a timeline, we only use
  select-tracks-for-object to check whether track elements should be
  added to the new track, not existing ones.
+ When removing a track from a timeline, we empty it of all the track
  elements that are controlled by a clip. Thus, we ensure that a clip
  only contains elements that are in the tracks of the same timeline, or
  no track. Similarly, when removing a clip from a timeline.
+ We can now avoid unsupported timeline configurations when a layer is
  added to a timeline, and already contains clips.
+ We can now avoid unsupported timeline configurations when a track is
  added to a timeline, and the timeline already contains clips.

Fixes https://gitlab.freedesktop.org/gstreamer/gst-editing-services/-/issues/84
2020-04-08 14:35:28 +01:00

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7 KiB
C

/* GStreamer Editing Services
* Copyright (C) 2009 Edward Hervey <edward.hervey@collabora.co.uk>
* 2009 Nokia Corporation
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#pragma once
#include <glib-object.h>
#include <gst/gst.h>
#include <ges/ges-timeline-element.h>
#include <ges/ges-container.h>
#include <ges/ges-types.h>
#include <ges/ges-track.h>
G_BEGIN_DECLS
#define GES_TYPE_CLIP ges_clip_get_type()
GES_DECLARE_TYPE(Clip, clip, CLIP);
/**
* GES_CLIP_CLASS_CAN_ADD_EFFECTS:
* @klass: A #GESClipClass
*
* Whether the class allows for the user to add additional non-core
* #GESBaseEffect-s to clips from this class.
*/
#define GES_CLIP_CLASS_CAN_ADD_EFFECTS(klass) ((GES_CLIP_CLASS (klass))->ABI.abi.can_add_effects)
/**
* GESFillTrackElementFunc:
* @clip: The #GESClip controlling the track elements
* @track_element: The #GESTrackElement
* @nleobj: The nleobject that needs to be filled
*
* A function that will be called when the nleobject of a corresponding
* track element needs to be filled.
*
* The implementer of this function shall add the proper #GstElement to @nleobj
* using gst_bin_add().
*
* Deprecated: 1.18: This method type is no longer used.
*
* Returns: %TRUE if the implementer successfully filled the @nleobj.
*/
typedef gboolean (*GESFillTrackElementFunc) (GESClip *clip, GESTrackElement *track_element,
GstElement *nleobj);
/**
* GESCreateTrackElementFunc:
* @clip: A #GESClip
* @type: A #GESTrackType to create a #GESTrackElement for
*
* A method for creating the core #GESTrackElement of a clip, to be added
* to a #GESTrack of the given track type.
*
* If a clip may produce several track elements per track type,
* #GESCreateTrackElementsFunc is more appropriate.
*
* Returns: (transfer floating) (nullable): The #GESTrackElement created
* by @clip, or %NULL if @clip can not provide a track element for the
* given @type or an error occurred.
*/
typedef GESTrackElement *(*GESCreateTrackElementFunc) (GESClip * clip, GESTrackType type);
/**
* GESCreateTrackElementsFunc:
* @clip: A #GESClip
* @type: A #GESTrackType to create #GESTrackElement-s for
*
* A method for creating the core #GESTrackElement-s of a clip, to be
* added to #GESTrack-s of the given track type.
*
* Returns: (transfer container) (element-type GESTrackElement): A list of
* the #GESTrackElement-s created by @clip for the given @type, or %NULL
* if no track elements are created or an error occurred.
*/
typedef GList * (*GESCreateTrackElementsFunc) (GESClip * clip, GESTrackType type);
/**
* GESClip:
*/
struct _GESClip
{
GESContainer parent;
/*< private >*/
GESClipPrivate *priv;
/* Padding for API extension */
gpointer _ges_reserved[GES_PADDING_LARGE];
};
/**
* GESClipClass:
* @create_track_element: Method to create the core #GESTrackElement of
* a clip of this class. If a clip of this class may create several track
* elements per track type, this should be left as %NULL, and
* create_track_elements() should be used instead. Otherwise, you should
* implement this class method and leave create_track_elements() as the
* default implementation
* @create_track_elements: Method to create the (multiple) core
* #GESTrackElement-s of a clip of this class. If create_track_element()
* is implemented, this should be kept as the default implementation
* @can_add_effects: Whether the user can add additional non-core
* #GESBaseEffect-s to clips from this class, to be applied to the output
* data of the core elements.
*/
struct _GESClipClass
{
/*< private > */
GESContainerClass parent_class;
/*< public > */
GESCreateTrackElementFunc create_track_element;
GESCreateTrackElementsFunc create_track_elements;
/*< private >*/
/* Padding for API extension */
union {
gpointer _ges_reserved[GES_PADDING_LARGE];
struct {
gboolean can_add_effects;
} abi;
} ABI;
};
/****************************************************
* TrackElement handling *
****************************************************/
GES_API
GESTrackType ges_clip_get_supported_formats (GESClip *clip);
GES_API
void ges_clip_set_supported_formats (GESClip *clip, GESTrackType supportedformats);
GES_API
GESTrackElement* ges_clip_add_asset (GESClip *clip, GESAsset *asset);
GES_API
GESTrackElement* ges_clip_find_track_element (GESClip *clip, GESTrack *track,
GType type);
GES_API
GList * ges_clip_find_track_elements (GESClip * clip, GESTrack * track,
GESTrackType track_type, GType type);
GES_API
GESTrackElement * ges_clip_add_child_to_track (GESClip * clip, GESTrackElement * child, GESTrack * track, GError **err);
/****************************************************
* Layer *
****************************************************/
GES_API
GESLayer* ges_clip_get_layer (GESClip *clip);
GES_API
gboolean ges_clip_move_to_layer (GESClip *clip, GESLayer *layer);
/****************************************************
* Effects *
****************************************************/
GES_API
GList* ges_clip_get_top_effects (GESClip *clip);
GES_API
gint ges_clip_get_top_effect_position (GESClip *clip, GESBaseEffect *effect);
GES_API
gint ges_clip_get_top_effect_index (GESClip *clip, GESBaseEffect *effect);
GES_API
gboolean ges_clip_set_top_effect_priority (GESClip *clip, GESBaseEffect *effect,
guint newpriority);
GES_API
gboolean ges_clip_set_top_effect_index (GESClip *clip, GESBaseEffect *effect,
guint newindex);
/****************************************************
* Editing *
****************************************************/
GES_API
GESClip* ges_clip_split (GESClip *clip, guint64 position);
GES_API
GstClockTime ges_clip_get_timeline_time_from_source_frame (GESClip * clip,
GESFrameNumber frame_number,
GError ** err);
G_END_DECLS