adg/adg-entity.c

   1 /* ADG - Automatic Drawing Generation
   2  * Copyright (C) 2007,2008,2009 Nicola Fontana <ntd at entidi.it>
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  17  * Boston, MA  02110-1301, USA.
  18  */
  19
  20
  21 /**
  22  * SECTION:adg-entity
  23  * @short_description: The base class for renderable objects
  24  *
  25  * This abstract class provides the base for all renderable objects.
  26  *
  27  * To provide a proper #AdgEntity derived type, you must at least
  28  * implement its arrange() and render() virtual methods. Also, if
  29  * you are using some sort of caching, ensure to clear it in the
  30  * invalidate() method.
  31  **/
  32
  33 /**
  34  * AdgEntity:
  35  *
  36  * All fields are private and should not be used directly.
  37  * Use its public methods instead.
  38  **/
  39
  40 /**
  41  * AdgEntityClass:
  42  * @parent_set: called after the parent has changed
  43  * @invalidate: invalidating callback, used to clear the cache
  44  * @arrange: prepare the layout and fill the extents struct
  45  * @render: rendering callback, it must be implemented
  46  *
  47  * Any entity (if not abstract) must implement at least the @render method.
  48  **/
  49
  50 /**
  51  * AdgEntityCallback:
  52  * @entity: an #AdgEntity
  53  * @user_data: a general purpose pointer
  54  *
  55  * Callback used when inspecting or browsing entities. For example,
  56  * it is passed to adg_model_foreach_dependency() to perform an
  57  * operation on all the entities depending on an #AdgModel.
  58  **/
  59
  60
  61 #include "adg-entity.h"
  62 #include "adg-entity-private.h"
  63 #include "adg-canvas.h"
  64 #include "adg-font-style.h"
  65 #include "adg-dim-style.h"
  66 #include "adg-marshal.h"
  67 #include "adg-intl.h"
  68
  69 #define PARENT_OBJECT_CLASS  ((GObjectClass *) adg_entity_parent_class)
  70
  71
  72 enum {
  73     PROP_0,
  74     PROP_PARENT,
  75     PROP_GLOBAL_MAP,
  76     PROP_LOCAL_MAP,
  77     PROP_LOCAL_METHOD
  78 };
  79
  80 enum {
  81     PARENT_SET,
  82     GLOBAL_CHANGED,
  83     LOCAL_CHANGED,
  84     INVALIDATE,
  85     ARRANGE,
  86     RENDER,
  87     LAST_SIGNAL
  88 };
  89
  90
  91 static void             dispose                 (GObject         *object);
  92 static void             get_property            (GObject         *object,
  93                                                  guint            prop_id,
  94                                                  GValue          *value,
  95                                                  GParamSpec      *pspec);
  96 static void             set_property            (GObject         *object,
  97                                                  guint            prop_id,
  98                                                  const GValue    *value,
  99                                                  GParamSpec      *pspec);
 100 static gboolean         set_parent              (AdgEntity       *entity,
 101                                                  AdgEntity       *parent);
 102 static gboolean         set_global_map          (AdgEntity       *entity,
 103                                                  const AdgMatrix *map);
 104 static gboolean         set_local_map           (AdgEntity       *entity,
 105                                                  const AdgMatrix *map);
 106 static gboolean         set_local_method        (AdgEntity       *entity,
 107                                                  AdgMixMethod     local_method);
 108 static void             global_changed          (AdgEntity       *entity);
 109 static void             local_changed           (AdgEntity       *entity);
 110 static void             real_invalidate         (AdgEntity       *entity);
 111 static void             real_arrange            (AdgEntity       *entity);
 112 static void             real_render             (AdgEntity       *entity,
 113                                                  cairo_t         *cr);
 114
 115 static guint    signals[LAST_SIGNAL] = { 0 };
 116 static gboolean show_extents = FALSE;
 117
 118
 119 G_DEFINE_ABSTRACT_TYPE(AdgEntity, adg_entity, G_TYPE_INITIALLY_UNOWNED);
 120
 121
 122 static void
 123 adg_entity_class_init(AdgEntityClass *klass)
 124 {
 125     GObjectClass *gobject_class;
 126     GParamSpec *param;
 127     GClosure *closure;
 128     GType param_types[1];
 129
 130     gobject_class = (GObjectClass *) klass;
 131
 132     g_type_class_add_private(klass, sizeof(AdgEntityPrivate));
 133
 134     gobject_class->dispose = dispose;
 135     gobject_class->get_property = get_property;
 136     gobject_class->set_property = set_property;
 137
 138     klass->parent_set = NULL;
 139     klass->global_changed = global_changed;
 140     klass->local_changed = local_changed;
 141     klass->invalidate = NULL;
 142     klass->arrange= NULL;
 143     klass->render = NULL;
 144
 145     param = g_param_spec_object("parent",
 146                                 P_("Parent Entity"),
 147                                 P_("The parent entity of this entity or NULL if this is a top-level entity"),
 148                                 ADG_TYPE_ENTITY,
 149                                 G_PARAM_READWRITE);
 150     g_object_class_install_property(gobject_class, PROP_PARENT, param);
 151
 152     param = g_param_spec_boxed("global-map",
 153                                P_("Global Map"),
 154                                P_("The transformation to be combined with the parent ones to get the global matrix"),
 155                                ADG_TYPE_MATRIX,
 156                                G_PARAM_READWRITE);
 157     g_object_class_install_property(gobject_class, PROP_GLOBAL_MAP, param);
 158
 159     param = g_param_spec_boxed("local-map",
 160                                P_("Local Map"),
 161                                P_("The local transformation that could be used to compute the local matrix in the way specified by the #AdgEntity:local-method property"),
 162                                ADG_TYPE_MATRIX,
 163                                G_PARAM_READWRITE);
 164     g_object_class_install_property(gobject_class, PROP_LOCAL_MAP, param);
 165
 166     param = g_param_spec_enum("local-method",
 167                               P_("Local Mix Method"),
 168                               P_("Define how the local maps of the entity and its ancestors should be combined to get the local matrix"),
 169                               ADG_TYPE_MIX_METHOD, ADG_MIX_ANCESTORS,
 170                               G_PARAM_READWRITE);
 171     g_object_class_install_property(gobject_class, PROP_LOCAL_METHOD, param);
 172
 173     /**
 174      * AdgEntity::parent-set:
 175      * @entity: an #AdgEntity
 176      * @old_parent: the old parent
 177      *
 178      * Emitted after the parent entity has changed. The new parent
 179      * can be inspected using adg_entity_get_parent().
 180      *
 181      * It is allowed for both old and new parent to be %NULL.
 182      **/
 183     signals[PARENT_SET] = g_signal_new("parent-set",
 184                                        G_OBJECT_CLASS_TYPE(gobject_class),
 185                                        G_SIGNAL_RUN_FIRST,
 186                                        G_STRUCT_OFFSET(AdgEntityClass, parent_set),
 187                                        NULL, NULL,
 188                                        adg_marshal_VOID__OBJECT,
 189                                        G_TYPE_NONE, 1, ADG_TYPE_ENTITY);
 190
 191     /**
 192      * AdgEntity::global-changed
 193      * @entity: an #AdgEntity
 194      *
 195      * Emitted when the global map of @entity or any of its parent
 196      * has changed. The default handler will compute the new global
 197      * matrix, updating the internal cache.
 198      **/
 199     signals[GLOBAL_CHANGED] = g_signal_new("global-changed",
 200                                            G_OBJECT_CLASS_TYPE(gobject_class),
 201                                            G_SIGNAL_RUN_FIRST,
 202                                            G_STRUCT_OFFSET(AdgEntityClass, global_changed),
 203                                            NULL, NULL,
 204                                            adg_marshal_VOID__VOID,
 205                                            G_TYPE_NONE, 0);
 206
 207     /**
 208      * AdgEntity::local-changed
 209      * @entity: an #AdgEntity
 210      *
 211      * Emitted when the local map of @entity or any of its parent
 212      * has changed. The default handler will compute the new local
 213      * matrix, updating the internal cache.
 214      **/
 215     signals[LOCAL_CHANGED] = g_signal_new("local-changed",
 216                                           G_OBJECT_CLASS_TYPE(gobject_class),
 217                                           G_SIGNAL_RUN_FIRST,
 218                                           G_STRUCT_OFFSET(AdgEntityClass, local_changed),
 219                                           NULL, NULL,
 220                                           adg_marshal_VOID__VOID,
 221                                           G_TYPE_NONE, 0);
 222
 223     /**
 224      * AdgEntity::invalidate:
 225      * @entity: an #AdgEntity
 226      *
 227      * Invalidates the whole @entity, that is resets all the cache
 228      * (if present) built during the #AdgEntity::arrange signal.
 229      * The resulting state is a clean entity, similar to what you
 230      * have just before the first rendering.
 231      **/
 232     closure = g_cclosure_new(G_CALLBACK(real_invalidate), NULL, NULL);
 233     signals[INVALIDATE] = g_signal_newv("invalidate", ADG_TYPE_ENTITY,
 234                                         G_SIGNAL_RUN_LAST, closure, NULL, NULL,
 235                                         adg_marshal_VOID__VOID,
 236                                         G_TYPE_NONE, 0, param_types);
 237
 238     /**
 239      * AdgEntity::arrange:
 240      * @entity: an #AdgEntity
 241      *
 242      * Arranges the layout of @entity, updating the cache if necessary,
 243      * and computes the extents of @entity.
 244      **/
 245     closure = g_cclosure_new(G_CALLBACK(real_arrange), NULL, NULL);
 246     signals[ARRANGE] = g_signal_newv("arrange", ADG_TYPE_ENTITY,
 247                                      G_SIGNAL_RUN_LAST, closure, NULL, NULL,
 248                                      adg_marshal_VOID__VOID,
 249                                      G_TYPE_NONE, 0, param_types);
 250     /**
 251      * AdgEntity::render:
 252      * @entity: an #AdgEntity
 253      * @cr: a #cairo_t drawing context
 254      *
 255      * Causes the rendering of @entity on @cr. A render signal will
 256      * automatically emit #AdgEntity::arrange just before the real
 257      * rendering on the cairo context.
 258      **/
 259     closure = g_cclosure_new(G_CALLBACK(real_render), NULL, NULL);
 260     param_types[0] = G_TYPE_POINTER;
 261     signals[RENDER] = g_signal_newv("render", ADG_TYPE_ENTITY,
 262                                     G_SIGNAL_RUN_LAST, closure, NULL, NULL,
 263                                     adg_marshal_VOID__POINTER,
 264                                     G_TYPE_NONE, 1, param_types);
 265 }
 266
 267 static void
 268 adg_entity_init(AdgEntity *entity)
 269 {
 270     AdgEntityPrivate *data = G_TYPE_INSTANCE_GET_PRIVATE(entity,
 271                                                          ADG_TYPE_ENTITY,
 272                                                          AdgEntityPrivate);
 273     data->parent = NULL;
 274     cairo_matrix_init_identity(&data->global_map);
 275     cairo_matrix_init_identity(&data->local_map);
 276     data->local_method = ADG_MIX_ANCESTORS;
 277     data->hash_styles = NULL;
 278     data->global.is_defined = FALSE;
 279     adg_matrix_copy(&data->global.matrix, adg_matrix_null());
 280     data->local.is_defined = FALSE;
 281     adg_matrix_copy(&data->local.matrix, adg_matrix_null());
 282     data->extents.is_defined = FALSE;
 283
 284     entity->data = data;
 285 }
 286
 287 static void
 288 dispose(GObject *object)
 289 {
 290     AdgEntity *entity;
 291     AdgEntityPrivate *data;
 292
 293     entity = (AdgEntity *) object;
 294     data = entity->data;
 295
 296     /* This call will emit a "notify" signal for parent.
 297      * Consequentially, the references to the old parent is dropped. */
 298     adg_entity_set_parent(entity, NULL);
 299
 300     if (data->hash_styles != NULL) {
 301         g_hash_table_destroy(data->hash_styles);
 302         data->hash_styles = NULL;
 303     }
 304
 305     if (PARENT_OBJECT_CLASS->dispose)
 306         PARENT_OBJECT_CLASS->dispose(object);
 307 }
 308
 309 static void
 310 get_property(GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
 311 {
 312     AdgEntity *entity;
 313     AdgEntityPrivate *data;
 314
 315     entity = (AdgEntity *) object;
 316     data = entity->data;
 317
 318     switch (prop_id) {
 319     case PROP_PARENT:
 320         g_value_set_object(value, data->parent);
 321         break;
 322     case PROP_GLOBAL_MAP:
 323         g_value_set_boxed(value, &data->global_map);
 324         break;
 325     case PROP_LOCAL_MAP:
 326         g_value_set_boxed(value, &data->local_map);
 327         break;
 328     case PROP_LOCAL_METHOD:
 329         g_value_set_enum(value, data->local_method);
 330         break;
 331     default:
 332         G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
 333         break;
 334     }
 335 }
 336
 337 static void
 338 set_property(GObject *object,
 339              guint prop_id, const GValue *value, GParamSpec *pspec)
 340 {
 341     AdgEntity *entity;
 342     AdgEntityPrivate *data;
 343
 344     entity = (AdgEntity *) object;
 345     data = entity->data;
 346
 347     switch (prop_id) {
 348     case PROP_PARENT:
 349         set_parent(entity, g_value_get_object(value));
 350         break;
 351     case PROP_GLOBAL_MAP:
 352         set_global_map(entity, g_value_get_boxed(value));
 353         break;
 354     case PROP_LOCAL_MAP:
 355         set_local_map(entity, g_value_get_boxed(value));
 356         break;
 357     case PROP_LOCAL_METHOD:
 358         set_local_method(entity, g_value_get_enum(value));
 359         break;
 360     default:
 361         G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
 362         break;
 363     }
 364 }
 365
 366
 367 /**
 368  * adg_switch_extents:
 369  * @state: new extents state
 370  *
 371  * Strokes (if @state is %TRUE) a rectangle around every entity to
 372  * show their extents. Useful for debugging purposes.
 373  **/
 374 void
 375 adg_switch_extents(gboolean state)
 376 {
 377     show_extents = state;
 378 }
 379
 380 /**
 381  * adg_entity_get_canvas:
 382  * @entity: an #AdgEntity
 383  *
 384  * Walks on the @entity hierarchy and gets the first parent of @entity that is
 385  * of #AdgCanvas derived type.
 386  *
 387  * Returns: the requested canvas or %NULL on errors or if there is
 388  *          no #AdgCanvas in the @entity hierarchy
 389  **/
 390 AdgCanvas *
 391 adg_entity_get_canvas(AdgEntity *entity)
 392 {
 393     g_return_val_if_fail(ADG_IS_ENTITY(entity), NULL);
 394
 395     while (entity) {
 396         if (ADG_IS_CANVAS(entity))
 397             return (AdgCanvas *) entity;
 398
 399         entity = adg_entity_get_parent(entity);
 400     }
 401
 402     return NULL;
 403 }
 404
 405 /**
 406  * adg_entity_set_parent:
 407  * @entity: an #AdgEntity
 408  * @parent: the parent entity
 409  *
 410  * <note><para>
 411  * This function is only useful in entity implementations.
 412  * </para></note>
 413  *
 414  * Sets a new parent on @entity.
 415  **/
 416 void
 417 adg_entity_set_parent(AdgEntity *entity, AdgEntity *parent)
 418 {
 419     g_return_if_fail(ADG_IS_ENTITY(entity));
 420
 421     if (set_parent(entity, parent))
 422         g_object_notify((GObject *) entity, "parent");
 423 }
 424
 425 /**
 426  * adg_entity_get_parent:
 427  * @entity: an #AdgEntity
 428  *
 429  * Gets the parent of @entity.
 430  *
 431  * Returns: the parent entity or %NULL on errors or if @entity is a toplevel
 432  **/
 433 AdgEntity *
 434 adg_entity_get_parent(AdgEntity *entity)
 435 {
 436     AdgEntityPrivate *data;
 437
 438     g_return_val_if_fail(ADG_IS_ENTITY(entity), NULL);
 439
 440     data = entity->data;
 441
 442     return data->parent;
 443 }
 444
 445 /**
 446  * adg_entity_set_global_map:
 447  * @entity: an #AdgEntity object
 448  * @map: the new map
 449  *
 450  * Sets the new global transformation of @entity to @map:
 451  * the old map is discarded. If @map is %NULL an identity
 452  * matrix is implied.
 453  **/
 454 void
 455 adg_entity_set_global_map(AdgEntity *entity, const AdgMatrix *map)
 456 {
 457     g_return_if_fail(ADG_IS_ENTITY(entity));
 458
 459     if (set_global_map(entity, map))
 460         g_object_notify((GObject *) entity, "global-map");
 461 }
 462
 463 /**
 464  * adg_entity_transform_global_map:
 465  * @entity: an #AdgEntity object
 466  * @transformation: the transformation to apply
 467  * @mode: how @transformation should be applied
 468  *
 469  * Convenient function to change the global map of @entity by
 470  * applying @tranformation using the @mode operator. This is
 471  * logically equivalent to the following:
 472  *
 473  * |[
 474  * AdgMatrix map;
 475  * adg_matrix_copy(&map, adg_entity_get_global_map(entity));
 476  * adg_matrix_transform(&map, transformation, mode);
 477  * adg_entity_set_global_map(entity, &map);
 478  * ]|
 479  **/
 480 void
 481 adg_entity_transform_global_map(AdgEntity *entity,
 482                                 const AdgMatrix *transformation,
 483                                 AdgTransformMode mode)
 484 {
 485     AdgEntityPrivate *data;
 486     AdgMatrix map;
 487
 488     g_return_if_fail(ADG_IS_ENTITY(entity));
 489     g_return_if_fail(transformation != NULL);
 490
 491     data = entity->data;
 492
 493     adg_matrix_copy(&map, &data->global_map);
 494     adg_matrix_transform(&map, transformation, mode);
 495
 496     if (set_global_map(entity, &map))
 497         g_object_notify((GObject *) entity, "global-map");
 498 }
 499
 500 /**
 501  * adg_entity_get_global_map:
 502  * @entity: an #AdgEntity object
 503  *
 504  * Gets the transformation to be used to compute the global matrix
 505  * of @entity.
 506  *
 507  * Returns: the requested map or %NULL on errors
 508  **/
 509 const AdgMatrix *
 510 adg_entity_get_global_map(AdgEntity *entity)
 511 {
 512     AdgEntityPrivate *data;
 513
 514     g_return_val_if_fail(ADG_IS_ENTITY(entity), NULL);
 515
 516     data = entity->data;
 517
 518     return &data->global_map;
 519 }
 520
 521 /**
 522  * adg_entity_get_global_matrix:
 523  * @entity: an #AdgEntity object
 524  *
 525  * Gets the current global matrix of @entity. The returned value
 526  * is owned by @entity and should not be changed or freed.
 527  *
 528  * The global matrix is computed in the arrange() phase by
 529  * combining all the global maps of the @entity hierarchy using
 530  * the %ADG_MIX_ANCESTORS method.
 531  *
 532  * Returns: the global matrix or %NULL on errors
 533  **/
 534 const AdgMatrix *
 535 adg_entity_get_global_matrix(AdgEntity *entity)
 536 {
 537     AdgEntityPrivate *data;
 538
 539     g_return_val_if_fail(ADG_IS_ENTITY(entity), NULL);
 540
 541     data = entity->data;
 542
 543     return &data->global.matrix;
 544 }
 545
 546 /**
 547  * adg_entity_set_local_map:
 548  * @entity: an #AdgEntity object
 549  * @map: the new map
 550  *
 551  * Sets the new local transformation of @entity to @map:
 552  * the old map is discarded. If @map is %NULL an identity
 553  * matrix is implied.
 554  **/
 555 void
 556 adg_entity_set_local_map(AdgEntity *entity, const AdgMatrix *map)
 557 {
 558     g_return_if_fail(ADG_IS_ENTITY(entity));
 559
 560     if (set_local_map(entity, map))
 561         g_object_notify((GObject *) entity, "local-map");
 562 }
 563
 564 /**
 565  * adg_entity_transform_local_map:
 566  * @entity: an #AdgEntity object
 567  * @transformation: the transformation to apply
 568  * @mode: how @transformation should be applied
 569  *
 570  * Convenient function to change the local map of @entity by
 571  * applying @tranformation using the @mode operator. This is
 572  * logically equivalent to the following:
 573  *
 574  * |[
 575  * AdgMatrix map;
 576  * adg_matrix_copy(&map, adg_entity_get_local_map(entity));
 577  * adg_matrix_transform(&map, transformation, mode);
 578  * adg_entity_set_local_map(entity, &map);
 579  * ]|
 580  **/
 581 void
 582 adg_entity_transform_local_map(AdgEntity *entity,
 583                                const AdgMatrix *transformation,
 584                                AdgTransformMode mode)
 585 {
 586     AdgEntityPrivate *data;
 587     AdgMatrix map;
 588
 589     g_return_if_fail(ADG_IS_ENTITY(entity));
 590     g_return_if_fail(transformation != NULL);
 591
 592     data = entity->data;
 593
 594     adg_matrix_copy(&map, &data->local_map);
 595     adg_matrix_transform(&map, transformation, mode);
 596
 597     if (set_local_map(entity, &map))
 598         g_object_notify((GObject *) entity, "local-map");
 599 }
 600
 601 /**
 602  * adg_entity_get_local_map:
 603  * @entity: an #AdgEntity object
 604  *
 605  * Gets the transformation to be used to compute the local matrix
 606  * of @entity and store it in @map.
 607  *
 608  * Returns: the requested map or %NULL on errors
 609  **/
 610 const AdgMatrix *
 611 adg_entity_get_local_map(AdgEntity *entity)
 612 {
 613     AdgEntityPrivate *data;
 614
 615     g_return_val_if_fail(ADG_IS_ENTITY(entity), NULL);
 616
 617     data = entity->data;
 618
 619     return &data->local_map;
 620 }
 621
 622 /**
 623  * adg_entity_get_local_matrix:
 624  * @entity: an #AdgEntity object
 625  *
 626  * Gets the current local matrix of @entity. The returned value
 627  * is owned by @entity and should not be changed or freed.
 628  *
 629  * The local matrix is computed in the arrange() phase by
 630  * combining all the local maps of the @entity hierarchy using
 631  * the method specified by the #AdgEntity:local-method property.
 632  *
 633  * Returns: the local matrix or %NULL on errors
 634  **/
 635 const AdgMatrix *
 636 adg_entity_get_local_matrix(AdgEntity *entity)
 637 {
 638     AdgEntityPrivate *data;
 639
 640     g_return_val_if_fail(ADG_IS_ENTITY(entity), NULL);
 641
 642     data = entity->data;
 643
 644     return &data->local.matrix;
 645 }
 646
 647 /**
 648  * adg_entity_set_local_method:
 649  * @entity: an #AdgEntity object
 650  * @local_method: new method
 651  *
 652  * Sets a new local mix method on @entity. The
 653  * #AdgEntity:local-method property defines how the local
 654  * matrix must be computed: check out the #AdgMixMethod
 655  * documentation to know what are the availables methods
 656  * and how they affect the local matrix computation.
 657  *
 658  * Setting a different local method emits an #Adgentity::local-changed
 659  * signal on @entity.
 660  **/
 661 void
 662 adg_entity_set_local_method(AdgEntity *entity, AdgMixMethod local_method)
 663 {
 664     g_return_if_fail(ADG_IS_ENTITY(entity));
 665
 666     if (set_local_method(entity, local_method))
 667         g_object_notify((GObject *) entity, "local-method");
 668 }
 669
 670 /**
 671  * adg_entity_get_local_method:
 672  * @entity: an #AdgEntity object
 673  *
 674  * Gets the local mix method of @entity. Check out the
 675  * adg_entity_set_local_method() documentation to know what the
 676  * local method is used for.
 677  *
 678  * Returns: the local method of @entity or %ADG_MIX_UNDEFINED on errors
 679  **/
 680 AdgMixMethod
 681 adg_entity_get_local_method(AdgEntity *entity)
 682 {
 683     AdgEntityPrivate *data;
 684
 685     g_return_val_if_fail(ADG_IS_ENTITY(entity), ADG_MIX_UNDEFINED);
 686
 687     data = entity->data;
 688
 689     return data->local_method;
 690 }
 691
 692 /**
 693  * adg_entity_set_extents:
 694  * @entity: an #AdgEntity
 695  * @extents: the new extents
 696  *
 697  * <note><para>
 698  * This function is only useful in entity implementations.
 699  * </para></note>
 700  *
 701  * Sets a new bounding box for @entity. @extents can be %NULL,
 702  * in which case the extents are unset.
 703  **/
 704 void
 705 adg_entity_set_extents(AdgEntity *entity, const CpmlExtents *extents)
 706 {
 707     AdgEntityPrivate *data;
 708
 709     g_return_if_fail(ADG_IS_ENTITY(entity));
 710
 711     data = entity->data;
 712
 713     if (extents == NULL)
 714         data->extents.is_defined = FALSE;
 715     else
 716         cpml_extents_copy(&data->extents, extents);
 717 }
 718
 719 /**
 720  * adg_entity_get_extents:
 721  * @entity: an #AdgEntity
 722  *
 723  * Gets the bounding box of @entity. The returned struct is
 724  * owned by @entity and should not modified or freed.
 725  *
 726  * This struct specifies the surface portion (in global space
 727  * of @entity) occupied by the entity without taking into
 728  * account rendering properties such as line thickness or caps.
 729  *
 730  * The #AdgEntity::arrange signal should be emitted before
 731  * this call (either explicitely trought adg_entity_arrange()
 732  * or implicitely with adg_entity_render()) in order to get
 733  * an up to date boundary box.
 734  *
 735  * Returns: the bounding box of @entity or %NULL on errors
 736  **/
 737 const CpmlExtents *
 738 adg_entity_get_extents(AdgEntity *entity)
 739 {
 740     AdgEntityPrivate *data;
 741
 742     g_return_val_if_fail(ADG_IS_ENTITY(entity), NULL);
 743
 744     data = entity->data;
 745
 746     return &data->extents;
 747 }
 748
 749 /**
 750  * adg_entity_set_style:
 751  * @entity: an #AdgEntity
 752  * @dress: a dress style
 753  * @style: the new style to use
 754  *
 755  * Overrides the style of @dress for @entity and its children.
 756  * If @style is %NULL, any previous override is removed.
 757  *
 758  * The new style must still be compatible with @dress: check out
 759  * the adg_dress_style_is_compatible() documentation to know
 760  * what a compatible style means.
 761  **/
 762 void
 763 adg_entity_set_style(AdgEntity *entity, AdgDress dress, AdgStyle *style)
 764 {
 765     AdgEntityPrivate *data;
 766     gpointer p_dress;
 767     AdgStyle *old_style;
 768
 769     g_return_if_fail(ADG_IS_ENTITY(entity));
 770
 771     data = entity->data;
 772
 773     if (data->hash_styles == NULL && style == NULL)
 774         return;
 775
 776     if (data->hash_styles == NULL)
 777         data->hash_styles = g_hash_table_new_full(NULL, NULL,
 778                                                   NULL, g_object_unref);
 779
 780     p_dress = GINT_TO_POINTER(dress);
 781     old_style = g_hash_table_lookup(data->hash_styles, p_dress);
 782
 783     if (style == old_style)
 784         return;
 785
 786     if (style == NULL) {
 787         g_hash_table_remove(data->hash_styles, p_dress);
 788         return;
 789     }
 790
 791     if (!adg_dress_style_is_compatible(dress, style)) {
 792         GType ancestor_type = adg_dress_get_ancestor_type(dress);
 793
 794         g_warning(_("%s: `%s' is not compatible with `%s' for `%s' dress"),
 795                   G_STRLOC, g_type_name(G_TYPE_FROM_INSTANCE(style)),
 796                   g_type_name(ancestor_type), adg_dress_get_name(dress));
 797
 798         return;
 799     }
 800
 801     g_object_ref(style);
 802     g_hash_table_replace(data->hash_styles, p_dress, style);
 803 }
 804
 805 /**
 806  * adg_entity_get_style:
 807  * @entity: an #AdgEntity
 808  * @dress: the dress of the style to get
 809  *
 810  * Gets the overriden @dress style from @entity. This is a kind
 811  * of accessor function: to get the style to be used for rendering
 812  * purpose, use adg_entity_style() instead.
 813  *
 814  * Returns: the requested style or %NULL if the @dress style
 815  *          is not overriden
 816  **/
 817 AdgStyle *
 818 adg_entity_get_style(AdgEntity *entity, AdgDress dress)
 819 {
 820     AdgEntityPrivate *data;
 821
 822     g_return_val_if_fail(ADG_IS_ENTITY(entity), NULL);
 823
 824     data = entity->data;
 825
 826     if (data->hash_styles == NULL)
 827         return NULL;
 828
 829     return g_hash_table_lookup(data->hash_styles, GINT_TO_POINTER(dress));
 830 }
 831
 832 /**
 833  * adg_entity_style:
 834  * @entity: an #AdgEntity
 835  * @dress: the dress of the style to get
 836  *
 837  * Gets the style to be used for @entity. @dress specifies which
 838  * "family" of style to get.
 839  *
 840  * The following sequence of checks is performed to get the proper
 841  * style, stopping at the first succesfull result:
 842  *
 843  * <orderedlist>
 844  * <listitem>check if the style is directly overriden by this entity,
 845  *           as returned by adg_entity_get_style();</listitem>
 846  * <listitem>check if @entity has a parent, in which case returns the
 847  *           adg_entity_style() of the parent;</listitem>
 848  * <listitem>returns the main style with adg_dress_get_fallback().</listitem>
 849  * </orderedlist>
 850  *
 851  * Returns: the requested style or %NULL for transparent dresses or errors
 852  **/
 853 AdgStyle *
 854 adg_entity_style(AdgEntity *entity, AdgDress dress)
 855 {
 856     AdgStyle *style;
 857
 858     g_return_val_if_fail(ADG_IS_ENTITY(entity), NULL);
 859
 860     style = adg_entity_get_style(entity, dress);
 861
 862     if (style == NULL) {
 863         AdgEntityPrivate *data = entity->data;
 864
 865         if (data->parent != NULL)
 866             style = adg_entity_style(data->parent, dress);
 867         else
 868             style = adg_dress_get_fallback(dress);
 869     }
 870
 871     return style;
 872 }
 873
 874 /**
 875  * adg_entity_apply_dress:
 876  * @entity: an #AdgEntity
 877  * @dress: the dress style to apply
 878  * @cr: a #cairo_t drawing context
 879  *
 880  * Convenient function to apply a @dress style (as returned by
 881  * adg_entity_style()) to the @cr cairo context.
 882  **/
 883 void
 884 adg_entity_apply_dress(AdgEntity *entity, AdgDress dress, cairo_t *cr)
 885 {
 886     AdgStyle *style;
 887
 888     g_return_if_fail(ADG_IS_ENTITY(entity));
 889     g_return_if_fail(cr != NULL);
 890
 891     style = adg_entity_style(entity, dress);
 892
 893     if (style != NULL)
 894         adg_style_apply(style, entity, cr);
 895 }
 896
 897 /**
 898  * adg_entity_global_changed:
 899  * @entity: an #AdgEntity
 900  *
 901  * Emits the #AdgEntity::global-changed signal on @entity and on all of
 902  * its children, if any.
 903  **/
 904 void
 905 adg_entity_global_changed(AdgEntity *entity)
 906 {
 907     g_return_if_fail(ADG_IS_ENTITY(entity));
 908
 909     g_signal_emit(entity, signals[GLOBAL_CHANGED], 0);
 910 }
 911
 912 /**
 913  * adg_entity_local_changed:
 914  * @entity: an #AdgEntity
 915  *
 916  * Emits the #AdgEntity::local-changed signal on @entity and on all of
 917  * its children, if any.
 918  **/
 919 void
 920 adg_entity_local_changed(AdgEntity *entity)
 921 {
 922     g_return_if_fail(ADG_IS_ENTITY(entity));
 923
 924     g_signal_emit(entity, signals[LOCAL_CHANGED], 0);
 925 }
 926
 927 /**
 928  * adg_entity_invalidate:
 929  * @entity: an #AdgEntity
 930  *
 931  * Emits the #AdgEntity::invalidate signal on @entity and on all of
 932  * its children, if any, clearing the eventual cache stored by the
 933  * #AdgEntity::arrange signal and setting the entity state similary
 934  * to the just initialized entity.
 935  **/
 936 void
 937 adg_entity_invalidate(AdgEntity *entity)
 938 {
 939     g_return_if_fail(ADG_IS_ENTITY(entity));
 940
 941     g_signal_emit(entity, signals[INVALIDATE], 0);
 942 }
 943
 944 /**
 945  * adg_entity_arrange:
 946  * @entity: an #AdgEntity
 947  *
 948  * Emits the #AdgEntity::arrange signal on @entity and all its children,
 949  * if any. This function is rarely needed as the arrange call is usually
 950  * implicitely called by the #AdgEntity::render signal or iby a call to
 951  * adg_entity_get_extents().
 952  **/
 953 void
 954 adg_entity_arrange(AdgEntity *entity)
 955 {
 956     g_return_if_fail(ADG_IS_ENTITY(entity));
 957
 958     g_signal_emit(entity, signals[ARRANGE], 0);
 959 }
 960
 961 /**
 962  * adg_entity_render:
 963  * @entity: an #AdgEntity
 964  * @cr: a #cairo_t drawing context
 965  *
 966  * Emits the #AdgEntity::render signal on @entity and on all of its
 967  * children, if any, causing the rendering to the @cr cairo context.
 968  **/
 969 void
 970 adg_entity_render(AdgEntity *entity, cairo_t *cr)
 971 {
 972     g_return_if_fail(ADG_IS_ENTITY(entity));
 973
 974     g_signal_emit(entity, signals[RENDER], 0, cr);
 975 }
 976
 977
 978 static gboolean
 979 set_parent(AdgEntity *entity, AdgEntity *parent)
 980 {
 981     AdgEntityPrivate *data;
 982     AdgEntity *old_parent;
 983
 984     data = entity->data;
 985     old_parent = data->parent;
 986
 987     /* Check if parent has changed */
 988     if (parent == old_parent)
 989         return FALSE;
 990
 991     if (parent != NULL)
 992         g_object_ref(parent);
 993
 994     data->parent = parent;
 995     data->global.is_defined = FALSE;
 996     data->local.is_defined = FALSE;
 997
 998     g_signal_emit(entity, signals[PARENT_SET], 0, old_parent);
 999
1000     if (old_parent != NULL)
1001         g_object_unref(old_parent);
1002
1003     return TRUE;
1004 }
1005
1006 static gboolean
1007 set_global_map(AdgEntity *entity, const AdgMatrix *map)
1008 {
1009     AdgEntityPrivate *data = entity->data;
1010
1011     if (map == NULL)
1012         map = adg_matrix_identity();
1013
1014     if (adg_matrix_equal(&data->global_map, map))
1015         return FALSE;
1016
1017     adg_matrix_copy(&data->global_map, map);
1018
1019     data->global.is_defined = FALSE;
1020     return TRUE;
1021 }
1022
1023 static gboolean
1024 set_local_map(AdgEntity *entity, const AdgMatrix *map)
1025 {
1026     AdgEntityPrivate *data = entity->data;
1027
1028     if (map == NULL)
1029         map = adg_matrix_identity();
1030
1031     if (adg_matrix_equal(&data->local_map, map))
1032         return FALSE;
1033
1034     adg_matrix_copy(&data->local_map, map);
1035
1036     data->local.is_defined = FALSE;
1037     return TRUE;
1038 }
1039
1040 static gboolean
1041 set_local_method(AdgEntity *entity, AdgMixMethod local_method)
1042 {
1043     AdgEntityPrivate *data = entity->data;
1044
1045     if (data->local_method == local_method)
1046         return FALSE;
1047
1048     data->local_method = local_method;
1049     g_signal_emit(entity, signals[LOCAL_CHANGED], 0);
1050
1051     return TRUE;
1052 }
1053
1054 static void
1055 global_changed(AdgEntity *entity)
1056 {
1057     AdgEntityPrivate *data;
1058     const AdgMatrix *map;
1059     AdgMatrix *matrix;
1060
1061     data = entity->data;
1062     map = &data->global_map;
1063     matrix = &data->global.matrix;
1064
1065     if (data->parent) {
1066         adg_matrix_copy(matrix, adg_entity_get_global_matrix(data->parent));
1067         adg_matrix_transform(matrix, map, ADG_TRANSFORM_BEFORE);
1068     } else {
1069         adg_matrix_copy(matrix, map);
1070     }
1071 }
1072
1073 static void
1074 local_changed(AdgEntity *entity)
1075 {
1076     AdgEntityPrivate *data;
1077     const AdgMatrix *map;
1078     AdgMatrix *matrix;
1079
1080     data = entity->data;
1081     map = &data->local_map;
1082     matrix = &data->local.matrix;
1083
1084     switch (data->local_method) {
1085     case ADG_MIX_DISABLED:
1086         adg_matrix_copy(matrix, adg_matrix_identity());
1087         break;
1088     case ADG_MIX_NONE:
1089         adg_matrix_copy(matrix, map);
1090         break;
1091     case ADG_MIX_ANCESTORS:
1092         if (data->parent) {
1093             adg_matrix_copy(matrix, adg_entity_get_local_matrix(data->parent));
1094             adg_matrix_transform(matrix, map, ADG_TRANSFORM_BEFORE);
1095         } else {
1096             adg_matrix_copy(matrix, map);
1097         }
1098         break;
1099     case ADG_MIX_ANCESTORS_NORMALIZED:
1100         if (data->parent) {
1101             adg_matrix_copy(matrix, adg_entity_get_local_matrix(data->parent));
1102             adg_matrix_transform(matrix, map, ADG_TRANSFORM_BEFORE);
1103         } else {
1104             adg_matrix_copy(matrix, map);
1105         }
1106         adg_matrix_normalize(matrix);
1107         break;
1108     case ADG_MIX_PARENT:
1109         if (data->parent) {
1110             adg_matrix_copy(matrix, adg_entity_get_local_map(data->parent));
1111             adg_matrix_transform(matrix, map, ADG_TRANSFORM_BEFORE);
1112         } else {
1113             adg_matrix_copy(matrix, map);
1114         }
1115         break;
1116     case ADG_MIX_PARENT_NORMALIZED:
1117         if (data->parent) {
1118             adg_matrix_copy(matrix, adg_entity_get_local_map(data->parent));
1119             adg_matrix_transform(matrix, map, ADG_TRANSFORM_BEFORE);
1120         } else {
1121             adg_matrix_copy(matrix, map);
1122         }
1123         adg_matrix_normalize(matrix);
1124         break;
1125     case ADG_MIX_UNDEFINED:
1126         g_warning(_("%s: requested to mix the maps using an undefined method"),
1127                   G_STRLOC);
1128         break;
1129     default:
1130         g_assert_not_reached();
1131         break;
1132     }
1133 }
1134
1135 static void
1136 real_invalidate(AdgEntity *entity)
1137 {
1138     AdgEntityClass *klass = ADG_ENTITY_GET_CLASS(entity);
1139     AdgEntityPrivate *data = entity->data;
1140
1141     /* Do not raise any warning if invalidate() is not defined,
1142      * assuming entity does not have additional cache to be cleared */
1143     if (klass->invalidate)
1144         klass->invalidate(entity);
1145
1146     data->extents.is_defined = FALSE;
1147 }
1148
1149 static void
1150 real_arrange(AdgEntity *entity)
1151 {
1152     AdgEntityClass *klass;
1153     AdgEntityPrivate *data;
1154
1155     klass = ADG_ENTITY_GET_CLASS(entity);
1156     data = entity->data;
1157
1158     /* Update the global matrix, if required */
1159     if (!data->global.is_defined) {
1160         data->global.is_defined = TRUE;
1161         g_signal_emit(entity, signals[GLOBAL_CHANGED], 0);
1162     }
1163
1164     /* Update the local matrix, if required */
1165     if (!data->local.is_defined) {
1166         data->local.is_defined = TRUE;
1167         g_signal_emit(entity, signals[LOCAL_CHANGED], 0);
1168     }
1169
1170     /* The arrange() method must be defined */
1171     if (klass->arrange == NULL) {
1172         g_warning(_("%s: `arrange' method not implemented for type `%s'"),
1173                   G_STRLOC, g_type_name(G_OBJECT_TYPE(entity)));
1174         data->extents.is_defined = FALSE;
1175         return;
1176     }
1177
1178     klass->arrange(entity);
1179 }
1180
1181 static void
1182 real_render(AdgEntity *entity, cairo_t *cr)
1183 {
1184     AdgEntityClass *klass = ADG_ENTITY_GET_CLASS(entity);
1185
1186     /* The render method must be defined */
1187     if (klass->render == NULL) {
1188         g_warning(_("%s: `render' method not implemented for type `%s'"),
1189                   G_STRLOC, g_type_name(G_OBJECT_TYPE(entity)));
1190         return;
1191     }
1192
1193     /* Before the rendering, the entity should be arranged */
1194     g_signal_emit(entity, signals[ARRANGE], 0);
1195
1196
1197     if (show_extents) {
1198         AdgEntityPrivate *data = entity->data;
1199
1200         if (data->extents.is_defined) {
1201             cairo_save(cr);
1202             cairo_identity_matrix(cr);
1203             cairo_set_line_width(cr, 1);
1204             cairo_set_antialias(cr, CAIRO_ANTIALIAS_NONE);
1205             cairo_rectangle(cr, data->extents.org.x, data->extents.org.y,
1206                             data->extents.size.x, data->extents.size.y);
1207             cairo_stroke(cr);
1208             cairo_restore(cr);
1209         }
1210     }
1211
1212     cairo_save(cr);
1213     cairo_set_matrix(cr, adg_entity_get_global_matrix(entity));
1214     klass->render(entity, cr);
1215     cairo_restore(cr);
1216 }