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

   1 /**
   2  * \file mlt_field.c
   3  * \brief a field for planting multiple transitions and filters
   4  *
   5  * Copyright (C) 2003-2008 Ushodaya Enterprises Limited
   6  * \author Charles Yates <charles.yates@pandora.be>
   7  *
   8  * This library is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with this library; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  */
  22
  23 #include "mlt_field.h"
  24 #include "mlt_service.h"
  25 #include "mlt_filter.h"
  26 #include "mlt_transition.h"
  27 #include "mlt_multitrack.h"
  28 #include "mlt_tractor.h"
  29
  30 #include <stdlib.h>
  31 #include <string.h>
  32
  33 /** \brief Field class
  34  *
  35  */
  36
  37 struct mlt_field_s
  38 {
  39         // This is the producer we're connected to
  40         mlt_service producer;
  41
  42         // Multitrack
  43         mlt_multitrack multitrack;
  44
  45         // Tractor
  46         mlt_tractor tractor;
  47 };
  48
  49 /** Constructor.
  50
  51         We construct a multitrack and a tractor here.
  52 */
  53
  54 mlt_field mlt_field_init( )
  55 {
  56         // Initialise the field
  57         mlt_field this = calloc( sizeof( struct mlt_field_s ), 1 );
  58
  59         // Initialise it
  60         if ( this != NULL )
  61         {
  62                 // Construct a multitrack
  63                 this->multitrack = mlt_multitrack_init( );
  64
  65                 // Construct a tractor
  66                 this->tractor = mlt_tractor_init( );
  67
  68                 // The first plant will be connected to the mulitrack
  69                 this->producer = MLT_MULTITRACK_SERVICE( this->multitrack );
  70
  71                 // Connect the tractor to the multitrack
  72                 mlt_tractor_connect( this->tractor, this->producer );
  73         }
  74
  75         // Return this
  76         return this;
  77 }
  78
  79 mlt_field mlt_field_new( mlt_multitrack multitrack, mlt_tractor tractor )
  80 {
  81         // Initialise the field
  82         mlt_field this = calloc( sizeof( struct mlt_field_s ), 1 );
  83
  84         // Initialise it
  85         if ( this != NULL )
  86         {
  87                 // Construct a multitrack
  88                 this->multitrack = multitrack;
  89
  90                 // Construct a tractor
  91                 this->tractor = tractor;
  92
  93                 // The first plant will be connected to the mulitrack
  94                 this->producer = MLT_MULTITRACK_SERVICE( this->multitrack );
  95
  96                 // Connect the tractor to the multitrack
  97                 mlt_tractor_connect( this->tractor, this->producer );
  98         }
  99
 100         // Return this
 101         return this;
 102 }
 103
 104 /** Get the service associated to this field.
 105 */
 106
 107 mlt_service mlt_field_service( mlt_field this )
 108 {
 109         return MLT_TRACTOR_SERVICE( this->tractor );
 110 }
 111
 112 /** Get the multi track.
 113 */
 114
 115 mlt_multitrack mlt_field_multitrack( mlt_field this )
 116 {
 117         return this != NULL ? this->multitrack : NULL;
 118 }
 119
 120 /** Get the tractor.
 121 */
 122
 123 mlt_tractor mlt_field_tractor( mlt_field this )
 124 {
 125         return this != NULL ? this->tractor : NULL;
 126 }
 127
 128 /** Get the properties associated to this field.
 129 */
 130
 131 mlt_properties mlt_field_properties( mlt_field this )
 132 {
 133         return MLT_SERVICE_PROPERTIES( mlt_field_service( this ) );
 134 }
 135
 136 /** Plant a filter.
 137 */
 138
 139 int mlt_field_plant_filter( mlt_field this, mlt_filter that, int track )
 140 {
 141         // Connect the filter to the last producer
 142         int result = mlt_filter_connect( that, this->producer, track );
 143
 144         // If sucessful, then we'll use this for connecting in the future
 145         if ( result == 0 )
 146         {
 147                 // This is now the new producer
 148                 this->producer = MLT_FILTER_SERVICE( that );
 149
 150                 // Reconnect tractor to new producer
 151                 mlt_tractor_connect( this->tractor, this->producer );
 152
 153                 // Fire an event
 154                 mlt_events_fire( mlt_field_properties( this ), "service-changed", NULL );
 155         }
 156
 157         return result;
 158 }
 159
 160 /** Plant a transition.
 161 */
 162
 163 int mlt_field_plant_transition( mlt_field this, mlt_transition that, int a_track, int b_track )
 164 {
 165         // Connect the transition to the last producer
 166         int result = mlt_transition_connect( that, this->producer, a_track, b_track );
 167
 168         // If sucessful, then we'll use this for connecting in the future
 169         if ( result == 0 )
 170         {
 171                 // This is now the new producer
 172                 this->producer = MLT_TRANSITION_SERVICE( that );
 173
 174                 // Reconnect tractor to new producer
 175                 mlt_tractor_connect( this->tractor, this->producer );
 176
 177                 // Fire an event
 178                 mlt_events_fire( mlt_field_properties( this ), "service-changed", NULL );
 179         }
 180
 181         return 0;
 182 }
 183
 184 /** Close the field.
 185 */
 186
 187 void mlt_field_close( mlt_field this )
 188 {
 189         if ( this != NULL && mlt_properties_dec_ref( mlt_field_properties( this ) ) <= 0 )
 190         {
 191                 //mlt_tractor_close( this->tractor );
 192                 //mlt_multitrack_close( this->multitrack );
 193                 free( this );
 194         }
 195 }
 196
 197 void mlt_field_disconnect_service( mlt_field self, mlt_service service )
 198 {
 199         mlt_service p = mlt_service_producer( service );
 200         mlt_service c = mlt_service_consumer( service);
 201         int i;
 202         switch ( mlt_service_identify(c) )
 203         {
 204                 case filter_type:
 205                         i = mlt_filter_get_track( MLT_FILTER(c) );
 206                         mlt_service_connect_producer( c, p, i );
 207                         break;
 208                 case transition_type:
 209                         i = mlt_transition_get_a_track ( MLT_TRANSITION(c) );
 210                         mlt_service_connect_producer( c, p, i );
 211                         MLT_TRANSITION(c)->producer = p;
 212                         break;
 213                 case tractor_type:
 214                         self->producer = p;
 215                         mlt_tractor_connect( MLT_TRACTOR(c), p );
 216                 default:
 217                         break;
 218         }
 219         mlt_events_fire( mlt_field_properties( self ), "service-changed", NULL );
 220 }