gstreamer/ges/ges-simple-timeline-layer.c
2010-06-09 18:56:55 +02:00

360 lines
10 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., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/**
* SECTION:ges-simple-timeline-layer
* @short_description: High-level #GESTimelineLayer
*
* #GESSimpleTimelineLayer allows using #GESTimelineObject(s) with a list-like
* API. Clients can add any type of GESTimelineObject to a
* GESSimpleTimelineLayer, and the layer will automatically compute the
* appropriate start times.
* Users should be aware that GESTimelineTransition objects are considered to
* have a negative duration for the purposes of positioning GESTimelineSource
* objects (i.e., adding a GESTimelineTransition creates an overlap between
* the two adjacent sources
*/
#include "ges-internal.h"
#include "ges-simple-timeline-layer.h"
#include "ges-timeline-object.h"
#include "ges-timeline-source.h"
#include "ges-timeline-transition.h"
static void
ges_simple_timeline_layer_object_removed (GESTimelineLayer * layer,
GESTimelineObject * object);
static void
ges_simple_timeline_layer_object_added (GESTimelineLayer * layer,
GESTimelineObject * object);
G_DEFINE_TYPE (GESSimpleTimelineLayer, ges_simple_timeline_layer,
GES_TYPE_TIMELINE_LAYER);
static void
ges_simple_timeline_layer_get_property (GObject * object,
guint property_id, GValue * value, GParamSpec * pspec)
{
switch (property_id) {
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}
}
static void
ges_simple_timeline_layer_set_property (GObject * object, guint property_id,
const GValue * value, GParamSpec * pspec)
{
switch (property_id) {
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}
}
static void
ges_simple_timeline_layer_dispose (GObject * object)
{
G_OBJECT_CLASS (ges_simple_timeline_layer_parent_class)->dispose (object);
}
static void
ges_simple_timeline_layer_finalize (GObject * object)
{
G_OBJECT_CLASS (ges_simple_timeline_layer_parent_class)->finalize (object);
}
static void
ges_simple_timeline_layer_class_init (GESSimpleTimelineLayerClass * klass)
{
GObjectClass *object_class = G_OBJECT_CLASS (klass);
GESTimelineLayerClass *layer_class = GES_TIMELINE_LAYER_CLASS (klass);
object_class->get_property = ges_simple_timeline_layer_get_property;
object_class->set_property = ges_simple_timeline_layer_set_property;
object_class->dispose = ges_simple_timeline_layer_dispose;
object_class->finalize = ges_simple_timeline_layer_finalize;
/* Be informed when objects are being added/removed from elsewhere */
layer_class->object_removed = ges_simple_timeline_layer_object_removed;
layer_class->object_added = ges_simple_timeline_layer_object_added;
}
static void
ges_simple_timeline_layer_init (GESSimpleTimelineLayer * self)
{
self->objects = NULL;
}
static void
gstl_recalculate (GESSimpleTimelineLayer * self)
{
GList *tmp;
GstClockTime pos = 0;
gint priority = 0;
gint transition_priority = 0;
GESTimelineObject *prev_object = NULL;
GESTimelineObject *prev_transition = NULL;
priority = GES_TIMELINE_LAYER (self)->min_gnl_priority;
GST_DEBUG ("recalculating values");
for (tmp = self->objects; tmp; tmp = tmp->next) {
GESTimelineObject *obj;
guint64 dur;
GList *l_next;
obj = (GESTimelineObject *) tmp->data;
dur = GES_TIMELINE_OBJECT_DURATION (obj);
GST_DEBUG ("obj: %p, %ld", obj, pos);
if (GES_IS_TIMELINE_SOURCE (obj)) {
priority++;
if (G_UNLIKELY (GES_TIMELINE_OBJECT_START (obj) != pos)) {
ges_timeline_object_set_start (obj, pos);
}
if (G_UNLIKELY (GES_TIMELINE_OBJECT_PRIORITY (obj) != priority)) {
ges_timeline_object_set_priority (obj, priority);
}
pos += dur;
g_assert (priority != -1);
} else if (GES_IS_TIMELINE_TRANSITION (obj)) {
GST_LOG ("%p is transition\n", obj);
pos -= dur;
transition_priority = MAX (0, priority - 1);
g_assert (transition_priority != -1);
if (G_UNLIKELY (GES_TIMELINE_OBJECT_START (obj) != pos))
ges_timeline_object_set_start (obj, pos);
if (G_UNLIKELY (GES_TIMELINE_OBJECT_PRIORITY (obj) !=
transition_priority)) {
ges_timeline_object_set_priority (obj, transition_priority);
}
/* sanity checks */
l_next = g_list_next (tmp);
if (GES_IS_TIMELINE_TRANSITION (prev_object)) {
GST_ERROR ("two transitions in sequence!");
}
if (prev_object && (GES_TIMELINE_OBJECT_DURATION (prev_object) < dur)) {
GST_ERROR ("transition duration exceeds that of previous neighbor!");
}
if (l_next && (GES_TIMELINE_OBJECT_DURATION (l_next->data) < dur)) {
GST_ERROR ("transition duration exceeds that of next neighbor!");
}
if (prev_transition) {
guint64 start, end;
end = (GES_TIMELINE_OBJECT_DURATION (prev_transition) +
GES_TIMELINE_OBJECT_START (prev_transition));
start = pos;
if (end > start)
GST_ERROR ("%d, %d: overlapping transitions!", start, end);
}
prev_transition = obj;
}
GST_LOG ("obj: %p, start: " GST_TIME_FORMAT " pri: %ld",
obj, GST_TIME_ARGS (pos), priority);
prev_object = obj;
}
GST_DEBUG ("Finished recalculating: final start pos is: " GST_TIME_FORMAT,
GST_TIME_ARGS (pos));
GES_TIMELINE_LAYER (self)->max_gnl_priority = priority;
}
/**
* ges_simple_timeline_layer_add_object:
* @layer: a #GESSimpleTimelineLayer
* @object: the #GESTimelineObject to add
* @position: the position at which to add the object
*
* Adds the object at the given position in the layer. The position is where
* the object will be inserted. To put the object before all objects, use
* position 0. To put after all objects, use position -1.
*
* When adding transitions, it is important that the adjacent objects
* (objects at position, and position + 1) be (1) A derivative of
* GESTimelineSource or other non-transition, and (2) have a duration at least
* as long as the duration of the transition.
*
* The layer will steal a reference to the provided object.
*
* Returns: TRUE if the object was successfuly added, else FALSE.
*/
gboolean
ges_simple_timeline_layer_add_object (GESSimpleTimelineLayer * layer,
GESTimelineObject * object, gint position)
{
gboolean res;
GList *nth;
GST_DEBUG ("layer:%p, object:%p, position:%d", layer, object, position);
nth = g_list_nth (layer->objects, position);
if (GES_IS_TIMELINE_TRANSITION (object)) {
GList *lprev = g_list_previous (nth);
GESTimelineObject *prev = GES_TIMELINE_OBJECT (lprev ? lprev->data : NULL);
GESTimelineObject *next = GES_TIMELINE_OBJECT (nth ? nth->data : NULL);
if ((prev && GES_IS_TIMELINE_TRANSITION (prev)) ||
(next && GES_IS_TIMELINE_TRANSITION (next))) {
GST_ERROR ("Not adding transition: Only insert transitions between two"
" sources, or at the begining or end the layer\n");
return FALSE;
}
}
layer->adding_object = TRUE;
res = ges_timeline_layer_add_object ((GESTimelineLayer *) layer, object);
/* Add to layer */
if (G_UNLIKELY (!res)) {
layer->adding_object = FALSE;
return FALSE;
}
layer->adding_object = FALSE;
GST_DEBUG ("Adding object %p to the list", object);
layer->objects = g_list_insert (layer->objects, object, position);
/* recalculate positions */
gstl_recalculate (layer);
return TRUE;
}
/**
* ges_simple_timeline_layer_move_object:
* @layer: a #GESSimpleTimelineLayer
* @object: the #GESTimelineObject to move
* @newposition: the new position at which to move the object
*
* Moves the object to the given position in the layer. To put the object before
* all other objects, use position 0. To put the objects after all objects, use
* position -1.
*
* Returns: TRUE if the object was successfuly moved, else FALSE.
*/
gboolean
ges_simple_timeline_layer_move_object (GESSimpleTimelineLayer * layer,
GESTimelineObject * object, gint newposition)
{
gint idx;
GST_DEBUG ("layer:%p, object:%p, newposition:%d", layer, object, newposition);
if (G_UNLIKELY (object->layer != (GESTimelineLayer *) layer)) {
GST_WARNING ("TimelineObject doesn't belong to this layer");
return FALSE;
}
/* Find it's current position */
idx = g_list_index (layer->objects, object);
if (G_UNLIKELY (idx == -1)) {
GST_WARNING ("TimelineObject not controlled by this layer");
return FALSE;
}
GST_DEBUG ("Object was previously at position %d", idx);
/* If we don't have to change its position, don't */
if (idx == newposition)
return TRUE;
/* pop it off the list */
layer->objects = g_list_remove (layer->objects, object);
/* re-add it at the proper position */
layer->objects = g_list_insert (layer->objects, object, (newposition >= 0
&& newposition < idx) ? newposition : newposition - 1);
/* recalculate positions */
gstl_recalculate (layer);
return TRUE;
}
/**
* ges_simple_timeline_layer_new:
*
* Creates a new #GESSimpleTimelineLayer.
*
* Returns: The new #GESSimpleTimelineLayer
*/
GESSimpleTimelineLayer *
ges_simple_timeline_layer_new (void)
{
return g_object_new (GES_TYPE_SIMPLE_TIMELINE_LAYER, NULL);
}
static void
ges_simple_timeline_layer_object_removed (GESTimelineLayer * layer,
GESTimelineObject * object)
{
GESSimpleTimelineLayer *sl = (GESSimpleTimelineLayer *) layer;
/* remove object from our list */
sl->objects = g_list_remove (sl->objects, object);
gstl_recalculate (sl);
}
static void
ges_simple_timeline_layer_object_added (GESTimelineLayer * layer,
GESTimelineObject * object)
{
GESSimpleTimelineLayer *sl = (GESSimpleTimelineLayer *) layer;
if (sl->adding_object == FALSE) {
/* remove object from our list */
sl->objects = g_list_append (sl->objects, object);
gstl_recalculate (sl);
}
g_signal_connect_swapped (object, "notify::duration",
G_CALLBACK (gstl_recalculate), layer);
}