adg/adg-toy-text.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-toy-text
  23  * @short_description: Simple text entity that use the cairo "toy" text API
  24  *
  25  * The #AdgToyText class is a basic class to show simple text. It internally
  26  * uses the so called cairo "toy" API and it shares the same limitations.
  27  *
  28  * The toy text entity is not subject to the local matrix, only its origin is.
  29  **/
  30
  31 /**
  32  * AdgToyText:
  33  *
  34  * All fields are privates and should not be used directly.
  35  * Use its public methods instead.
  36  **/
  37
  38
  39 #include "adg-toy-text.h"
  40 #include "adg-toy-text-private.h"
  41 #include "adg-font-style.h"
  42 #include "adg-intl.h"
  43
  44 #define PARENT_OBJECT_CLASS  ((GObjectClass *) adg_toy_text_parent_class)
  45 #define PARENT_ENTITY_CLASS  ((AdgEntityClass *) adg_toy_text_parent_class)
  46
  47
  48 enum {
  49     PROP_0,
  50     PROP_DRESS,
  51     PROP_LABEL
  52 };
  53
  54
  55 static void     finalize                (GObject        *object);
  56 static void     get_property            (GObject        *object,
  57                                          guint           param_id,
  58                                          GValue         *value,
  59                                          GParamSpec     *pspec);
  60 static void     set_property            (GObject        *object,
  61                                          guint           param_id,
  62                                          const GValue   *value,
  63                                          GParamSpec     *pspec);
  64 static void     global_changed          (AdgEntity      *entity);
  65 static void     local_changed           (AdgEntity      *entity);
  66 static void     invalidate              (AdgEntity      *entity);
  67 static void     arrange                 (AdgEntity      *entity);
  68 static void     render                  (AdgEntity      *entity,
  69                                          cairo_t        *cr);
  70 static gboolean set_dress               (AdgToyText     *toy_text,
  71                                          AdgDress        dress);
  72 static gboolean set_label               (AdgToyText     *toy_text,
  73                                          const gchar    *label);
  74 static void     unset_font              (AdgToyText     *toy_text);
  75 static void     unset_glyphs            (AdgToyText     *toy_text);
  76
  77
  78 G_DEFINE_TYPE(AdgToyText, adg_toy_text, ADG_TYPE_ENTITY);
  79
  80
  81 static void
  82 adg_toy_text_class_init(AdgToyTextClass *klass)
  83 {
  84     GObjectClass *gobject_class;
  85     AdgEntityClass *entity_class;
  86     GParamSpec *param;
  87
  88     gobject_class = (GObjectClass *) klass;
  89     entity_class = (AdgEntityClass *) klass;
  90
  91     g_type_class_add_private(klass, sizeof(AdgToyTextPrivate));
  92
  93     gobject_class->finalize = finalize;
  94     gobject_class->get_property = get_property;
  95     gobject_class->set_property = set_property;
  96
  97     entity_class->global_changed = global_changed;
  98     entity_class->local_changed = local_changed;
  99     entity_class->invalidate = invalidate;
 100     entity_class->arrange = arrange;
 101     entity_class->render = render;
 102
 103     param = adg_param_spec_dress("dress",
 104                                  P_("Font Dress"),
 105                                  P_("The font dress to use for rendering this text"),
 106                                  ADG_DRESS_TEXT_REGULAR,
 107                                  G_PARAM_READWRITE);
 108     g_object_class_install_property(gobject_class, PROP_DRESS, param);
 109
 110     param = g_param_spec_string("label",
 111                                 P_("Label"),
 112                                 P_("The label to display"),
 113                                 NULL,
 114                                 G_PARAM_READWRITE);
 115     g_object_class_install_property(gobject_class, PROP_LABEL, param);
 116 }
 117
 118 static void
 119 adg_toy_text_init(AdgToyText *toy_text)
 120 {
 121     AdgToyTextPrivate *data = G_TYPE_INSTANCE_GET_PRIVATE(toy_text,
 122                                                           ADG_TYPE_TOY_TEXT,
 123                                                           AdgToyTextPrivate);
 124
 125     data->dress = ADG_DRESS_TEXT_REGULAR;
 126     data->label = NULL;
 127     data->glyphs = NULL;
 128
 129     toy_text->data = data;
 130 }
 131
 132 static void
 133 finalize(GObject *object)
 134 {
 135     AdgToyText *toy_text;
 136     AdgToyTextPrivate *data;
 137
 138     toy_text = (AdgToyText *) object;
 139     data = toy_text->data;
 140
 141     g_free(data->label);
 142     unset_font(toy_text);
 143     unset_glyphs(toy_text);
 144
 145     if (PARENT_OBJECT_CLASS->finalize != NULL)
 146         PARENT_OBJECT_CLASS->finalize(object);
 147 }
 148
 149 static void
 150 get_property(GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
 151 {
 152     AdgToyTextPrivate *data = ((AdgToyText *) object)->data;
 153
 154     switch (prop_id) {
 155     case PROP_DRESS:
 156         g_value_set_int(value, data->dress);
 157         break;
 158     case PROP_LABEL:
 159         g_value_set_string(value, data->label);
 160         break;
 161     default:
 162         G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
 163         break;
 164     }
 165 }
 166
 167 static void
 168 set_property(GObject *object, guint prop_id,
 169              const GValue *value, GParamSpec *pspec)
 170 {
 171     AdgToyText *toy_text = (AdgToyText *) object;
 172
 173     switch (prop_id) {
 174     case PROP_DRESS:
 175         set_dress(toy_text, g_value_get_int(value));
 176         break;
 177     case PROP_LABEL:
 178         set_label(toy_text, g_value_get_string(value));
 179         break;
 180     default:
 181         G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
 182         break;
 183     }
 184 }
 185
 186
 187 /**
 188  * adg_toy_text_new:
 189  * @label: the label text
 190  *
 191  * Creates a new toy text entity using @label as its text
 192  *
 193  * Returns: the newly created toy text entity
 194  **/
 195 AdgToyText *
 196 adg_toy_text_new(const gchar *label)
 197 {
 198     return g_object_new(ADG_TYPE_TOY_TEXT, "label", label, NULL);
 199 }
 200
 201 /**
 202  * adg_toy_text_get_dress:
 203  * @toy_text: an #AdgToyText
 204  *
 205  * Gets the font dress to be used in rendering @toy_text.
 206  *
 207  * Returns: the current font dress
 208  **/
 209 AdgDress
 210 adg_toy_text_get_dress(AdgToyText *toy_text)
 211 {
 212     AdgToyTextPrivate *data;
 213
 214     g_return_val_if_fail(ADG_IS_TOY_TEXT(toy_text), ADG_DRESS_UNDEFINED);
 215
 216     data = toy_text->data;
 217
 218     return data->dress;
 219 }
 220
 221 /**
 222  * adg_toy_text_set_dress:
 223  * @toy_text: an #AdgToyText
 224  * @dress: the new #AdgDress to use
 225  *
 226  * Sets a new font dress for rendering @toy_text. The new dress
 227  * must be related to the original dress for this property:
 228  * you cannot set a dress used for line styles to a dress
 229  * managing fonts.
 230  *
 231  * The check is done by calling adg_dress_are_related() with
 232  * @dress and the previous dress as arguments. Check out its
 233  * documentation for details on what is a related dress.
 234  **/
 235 void
 236 adg_toy_text_set_dress(AdgToyText *toy_text, AdgDress dress)
 237 {
 238     g_return_if_fail(ADG_IS_TOY_TEXT(toy_text));
 239
 240     if (set_dress(toy_text, dress))
 241         g_object_notify((GObject *) toy_text, "dress");
 242 }
 243
 244 /**
 245  * adg_toy_text_get_label:
 246  * @toy_text: an #AdgToyText
 247  *
 248  * Gets the label text. The string is internally owned and
 249  * must not be freed or modified.
 250  *
 251  * Returns: the label text
 252  **/
 253 const gchar *
 254 adg_toy_text_get_label(AdgToyText *toy_text)
 255 {
 256     AdgToyTextPrivate *data;
 257
 258     g_return_val_if_fail(ADG_IS_TOY_TEXT(toy_text), NULL);
 259
 260     data = toy_text->data;
 261
 262     return data->label;
 263 }
 264
 265 /**
 266  * adg_toy_text_set_label:
 267  * @toy_text: an #AdgToyText
 268  * @label: the label text
 269  *
 270  * Sets a new label for @toy_text. @label can be also %NULL,
 271  * in which case will be treated as an empty string.
 272  **/
 273 void
 274 adg_toy_text_set_label(AdgToyText *toy_text, const gchar *label)
 275 {
 276     g_return_if_fail(ADG_IS_TOY_TEXT(toy_text));
 277
 278     if (set_label(toy_text, label))
 279         g_object_notify((GObject *) toy_text, "label");
 280 }
 281
 282
 283 static void
 284 global_changed(AdgEntity *entity)
 285 {
 286     unset_font((AdgToyText *) entity);
 287
 288     PARENT_ENTITY_CLASS->global_changed(entity);
 289 }
 290
 291 static void
 292 local_changed(AdgEntity *entity)
 293 {
 294     AdgMatrix old, new;
 295     CpmlExtents extents;
 296
 297     adg_entity_get_local_matrix(entity, &old);
 298
 299     PARENT_ENTITY_CLASS->local_changed(entity);
 300
 301     adg_entity_get_local_matrix(entity, &new);
 302     cairo_matrix_init_translate(&new, new.x0, new.y0);
 303     adg_entity_set_local_matrix(entity, &new);
 304
 305     /* Update the extents position (if needed) without
 306      * invalidating the font */
 307     adg_entity_get_extents(entity, &extents);
 308
 309     if (extents.is_defined) {
 310         extents.org.x += new.x0 - old.x0;
 311         extents.org.y += new.y0 - old.y0;
 312         adg_entity_set_extents(entity, &extents);
 313     }
 314 }
 315
 316 static void
 317 invalidate(AdgEntity *entity)
 318 {
 319     unset_font((AdgToyText *) entity);
 320     unset_glyphs((AdgToyText *) entity);
 321
 322     if (PARENT_ENTITY_CLASS->invalidate != NULL)
 323         return PARENT_ENTITY_CLASS->invalidate(entity);
 324 }
 325
 326 static void
 327 arrange(AdgEntity *entity)
 328 {
 329     AdgToyText *toy_text;
 330     AdgToyTextPrivate *data;
 331     cairo_status_t status;
 332     cairo_text_extents_t cairo_extents;
 333     AdgMatrix local;
 334     CpmlExtents extents;
 335
 336     toy_text = (AdgToyText *) entity;
 337     data = toy_text->data;
 338
 339     if (data->font == NULL) {
 340         AdgFontStyle *font_style;
 341         AdgMatrix ctm;
 342
 343         font_style = (AdgFontStyle *) adg_entity_style(entity, data->dress);
 344         adg_entity_get_global_matrix(entity, &ctm);
 345         data->font = adg_font_style_font(font_style, &ctm);
 346     }
 347
 348     if (data->glyphs != NULL || data->label == NULL || data->label[0] == '\0')
 349         return;
 350
 351     status = cairo_scaled_font_text_to_glyphs(data->font, 0, 0,
 352                                               data->label, -1,
 353                                               &data->glyphs,
 354                                               &data->num_glyphs,
 355                                               NULL, NULL, NULL);
 356
 357     if (status != CAIRO_STATUS_SUCCESS) {
 358         unset_glyphs(toy_text);
 359         g_error("Unable to build glyphs (cairo message: %s)",
 360                 cairo_status_to_string(status));
 361         return;
 362     }
 363
 364     cairo_scaled_font_glyph_extents(data->font, data->glyphs,
 365                                     data->num_glyphs, &cairo_extents);
 366     cpml_extents_from_cairo_text(&extents, &cairo_extents);
 367
 368     adg_entity_get_local_map(entity, &local);
 369     cairo_matrix_transform_point(&local, &extents.org.x, &extents.org.y);
 370     cairo_matrix_transform_distance(&local, &extents.size.x, &extents.size.y);
 371
 372     adg_entity_set_extents(entity, &extents);
 373 }
 374
 375 static void
 376 render(AdgEntity *entity, cairo_t *cr)
 377 {
 378     AdgToyText *toy_text;
 379     AdgToyTextPrivate *data;
 380
 381     toy_text = (AdgToyText *) entity;
 382     data = toy_text->data;
 383
 384     if (data->glyphs != NULL) {
 385         cairo_save(cr);
 386         cairo_set_scaled_font(cr, data->font);
 387         adg_entity_apply_local_matrix(entity, cr);
 388         cairo_show_glyphs(cr, data->glyphs, data->num_glyphs);
 389         cairo_restore(cr);
 390     }
 391 }
 392
 393 static gboolean
 394 set_dress(AdgToyText *toy_text, AdgDress dress)
 395 {
 396     AdgToyTextPrivate *data = toy_text->data;
 397
 398     if (adg_dress_set(&data->dress, dress)) {
 399         unset_font(toy_text);
 400         return TRUE;
 401     }
 402
 403     return FALSE;
 404 }
 405
 406 static gboolean
 407 set_label(AdgToyText *toy_text, const gchar *label)
 408 {
 409     AdgToyTextPrivate *data = toy_text->data;
 410
 411     /* Check if the new label differs from the current label */
 412     if (adg_strcmp(label, data->label) == 0)
 413         return FALSE;
 414
 415     g_free(data->label);
 416     data->label = g_strdup(label);
 417
 418     unset_glyphs(toy_text);
 419     return TRUE;
 420 }
 421
 422 static void
 423 unset_font(AdgToyText *toy_text)
 424 {
 425     AdgToyTextPrivate *data = toy_text->data;
 426
 427     data->font = NULL;
 428 }
 429
 430 static void
 431 unset_glyphs(AdgToyText *toy_text)
 432 {
 433     AdgToyTextPrivate *data = toy_text->data;
 434
 435     if (data->glyphs != NULL) {
 436         cairo_glyph_free(data->glyphs);
 437         data->glyphs = NULL;
 438     }
 439
 440     data->num_glyphs = 0;
 441 }