research.m1stereo.tv/gitweb/ - melted/blob - src/framework/mlt_field.c

   1 /*
   2  * mlt_field.c -- A field for planting multiple transitions and filters
   3  * Copyright (C) 2003-2004 Ushodaya Enterprises Limited
   4  * Author: Charles Yates <charles.yates@pandora.be>
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #include "mlt_field.h"
  22 #include "mlt_service.h"
  23 #include "mlt_filter.h"
  24 #include "mlt_transition.h"
  25 #include "mlt_multitrack.h"
  26 #include "mlt_tractor.h"
  27
  28 #include <stdlib.h>
  29 #include <string.h>
  30
  31 /** Private structures.
  32 */
  33
  34 struct mlt_field_s
  35 {
  36         // This is the producer we're connected to
  37         mlt_service producer;
  38
  39         // Multitrack
  40         mlt_multitrack multitrack;
  41
  42         // Tractor
  43         mlt_tractor tractor;
  44 };
  45
  46 /** Constructor.
  47
  48         We construct a multitrack and a tractor here.
  49 */
  50
  51 mlt_field mlt_field_init( )
  52 {
  53         // Initialise the field
  54         mlt_field this = calloc( sizeof( struct mlt_field_s ), 1 );
  55
  56         // Initialise it
  57         if ( this != NULL )
  58         {
  59                 // Construct a multitrack
  60                 this->multitrack = mlt_multitrack_init( );
  61
  62                 // Construct a tractor
  63                 this->tractor = mlt_tractor_init( );
  64
  65                 // The first plant will be connected to the mulitrack
  66                 this->producer = MLT_MULTITRACK_SERVICE( this->multitrack );
  67
  68                 // Connect the tractor to the multitrack
  69                 mlt_tractor_connect( this->tractor, this->producer );
  70         }
  71
  72         // Return this
  73         return this;
  74 }
  75
  76 mlt_field mlt_field_new( mlt_multitrack multitrack, mlt_tractor tractor )
  77 {
  78         // Initialise the field
  79         mlt_field this = calloc( sizeof( struct mlt_field_s ), 1 );
  80
  81         // Initialise it
  82         if ( this != NULL )
  83         {
  84                 // Construct a multitrack
  85                 this->multitrack = multitrack;
  86
  87                 // Construct a tractor
  88                 this->tractor = tractor;
  89
  90                 // The first plant will be connected to the mulitrack
  91                 this->producer = MLT_MULTITRACK_SERVICE( this->multitrack );
  92
  93                 // Connect the tractor to the multitrack
  94                 mlt_tractor_connect( this->tractor, this->producer );
  95         }
  96
  97         // Return this
  98         return this;
  99 }
 100
 101 /** Get the service associated to this field.
 102 */
 103
 104 mlt_service mlt_field_service( mlt_field this )
 105 {
 106         return MLT_TRACTOR_SERVICE( this->tractor );
 107 }
 108
 109 /** Get the multi track.
 110 */
 111
 112 mlt_multitrack mlt_field_multitrack( mlt_field this )
 113 {
 114         return this != NULL ? this->multitrack : NULL;
 115 }
 116
 117 /** Get the tractor.
 118 */
 119
 120 mlt_tractor mlt_field_tractor( mlt_field this )
 121 {
 122         return this != NULL ? this->tractor : NULL;
 123 }
 124
 125 /** Get the properties associated to this field.
 126 */
 127
 128 mlt_properties mlt_field_properties( mlt_field this )
 129 {
 130         return MLT_SERVICE_PROPERTIES( mlt_field_service( this ) );
 131 }
 132
 133 /** Plant a filter.
 134 */
 135
 136 int mlt_field_plant_filter( mlt_field this, mlt_filter that, int track )
 137 {
 138         // Connect the filter to the last producer
 139         int result = mlt_filter_connect( that, this->producer, track );
 140
 141         // If sucessful, then we'll use this for connecting in the future
 142         if ( result == 0 )
 143         {
 144                 // This is now the new producer
 145                 this->producer = MLT_FILTER_SERVICE( that );
 146
 147                 // Reconnect tractor to new producer
 148                 mlt_tractor_connect( this->tractor, this->producer );
 149
 150                 // Fire an event
 151                 mlt_events_fire( mlt_field_properties( this ), "service-changed", NULL );
 152         }
 153
 154         return result;
 155 }
 156
 157 /** Plant a transition.
 158 */
 159
 160 int mlt_field_plant_transition( mlt_field this, mlt_transition that, int a_track, int b_track )
 161 {
 162         // Connect the transition to the last producer
 163         int result = mlt_transition_connect( that, this->producer, a_track, b_track );
 164
 165         // If sucessful, then we'll use this for connecting in the future
 166         if ( result == 0 )
 167         {
 168                 // This is now the new producer
 169                 this->producer = MLT_TRANSITION_SERVICE( that );
 170
 171                 // Reconnect tractor to new producer
 172                 mlt_tractor_connect( this->tractor, this->producer );
 173
 174                 // Fire an event
 175                 mlt_events_fire( mlt_field_properties( this ), "service-changed", NULL );
 176         }
 177
 178         return 0;
 179 }
 180
 181 /** Close the field.
 182 */
 183
 184 void mlt_field_close( mlt_field this )
 185 {
 186         if ( this != NULL && mlt_properties_dec_ref( mlt_field_properties( this ) ) <= 0 )
 187         {
 188                 //mlt_tractor_close( this->tractor );
 189                 //mlt_multitrack_close( this->multitrack );
 190                 free( this );
 191         }
 192 }
 193
 194 void mlt_field_disconnect_service( mlt_field self, mlt_service service )
 195 {
 196         mlt_service p = mlt_service_producer( service );
 197         mlt_service c = mlt_service_consumer( service);
 198         int i;
 199         switch ( mlt_service_identify(c) )
 200         {
 201                 case filter_type:
 202                         i = mlt_filter_get_track( MLT_FILTER(c) );
 203                         mlt_service_connect_producer( c, p, i );
 204                         break;
 205                 case transition_type:
 206                         i = mlt_transition_get_a_track ( MLT_TRANSITION(c) );
 207                         mlt_service_connect_producer( c, p, i );
 208                         break;
 209                 case tractor_type:
 210                         self->producer = p;
 211                         mlt_tractor_connect( MLT_TRACTOR(c), p );
 212                 default:
 213                         break;
 214         }
 215         mlt_events_fire( mlt_field_properties( self ), "service-changed", NULL );
 216 }