aspectbin.c

   1 /* AspectBin - A GTK+ container for packing with consrained aspect ratio.
   2  * Copyright (C) 2009 Nick Bowler
   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., 59 Temple Place - Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  */
  19
  20 #include <stdio.h>
  21 #include "aspectbin.h"
  22
  23 enum {
  24         PROP_0,
  25         PROP_RATIO,
  26         PROP_CONSTRAIN,
  27         PROP_FILL,
  28 };
  29
  30 enum {
  31         CHILD_PROP_0,
  32         CHILD_PROP_ALIGN,
  33 };
  34
  35 static void aspect_bin_size_request(GtkWidget *, GtkRequisition *);
  36 static void aspect_bin_size_allocate(GtkWidget *, GtkAllocation *);
  37 static void aspect_bin_add(GtkContainer *, GtkWidget *);
  38 static void aspect_bin_remove(GtkContainer *, GtkWidget *);
  39 static void aspect_bin_forall(GtkContainer *, gboolean, GtkCallback, gpointer);
  40 static GType aspect_bin_child_type(GtkContainer *);
  41
  42 static void aspect_bin_get_property(GObject *, guint, GValue *, GParamSpec *);
  43 static void aspect_bin_set_property(GObject *, guint, const GValue *,
  44                                                           GParamSpec *);
  45 static void aspect_bin_set_child_property(GtkContainer *, GtkWidget *, guint,
  46                                                 const GValue *, GParamSpec *);
  47 static void aspect_bin_get_child_property(GtkContainer *, GtkWidget *, guint,
  48                                                       GValue *, GParamSpec *);
  49
  50 G_DEFINE_TYPE(AspectBin, aspect_bin, GTK_TYPE_CONTAINER)
  51
  52 static void aspect_bin_init(AspectBin *abin)
  53 {
  54         GTK_WIDGET_SET_FLAGS(abin, GTK_NO_WINDOW);
  55
  56         abin->body       = NULL;
  57         abin->side       = NULL;
  58         abin->ratio      = 1;
  59         abin->body_align = 0.5;
  60         abin->side_align = 0.5;
  61         abin->constrain  = FALSE;
  62         abin->fill       = TRUE;
  63 }
  64
  65 static void aspect_bin_class_init(AspectBinClass *class)
  66 {
  67         GObjectClass      *object_class    = G_OBJECT_CLASS(class);
  68         GtkWidgetClass    *widget_class    = GTK_WIDGET_CLASS(class);
  69         GtkContainerClass *container_class = GTK_CONTAINER_CLASS(class);
  70
  71         widget_class->size_request  = aspect_bin_size_request;
  72         widget_class->size_allocate = aspect_bin_size_allocate;
  73
  74         container_class->add        = aspect_bin_add;
  75         container_class->remove     = aspect_bin_remove;
  76         container_class->forall     = aspect_bin_forall;
  77         container_class->child_type = aspect_bin_child_type;
  78
  79         container_class->set_child_property = aspect_bin_set_child_property;
  80         container_class->get_child_property = aspect_bin_get_child_property;
  81
  82         object_class->set_property = aspect_bin_set_property;
  83         object_class->get_property = aspect_bin_get_property;
  84
  85         g_object_class_install_property(object_class,
  86                 PROP_RATIO,
  87                 g_param_spec_float("ratio",
  88                         "Aspect Ratio",
  89                         "Width:height ratio of the body.",
  90                         0.2, 5.0, 1.0,
  91                         G_PARAM_READWRITE));
  92         g_object_class_install_property(object_class,
  93                 PROP_FILL,
  94                 g_param_spec_boolean("fill",
  95                         "Fill",
  96                         "Allocate all remaining space to the side.",
  97                         TRUE,
  98                         G_PARAM_READWRITE));
  99         g_object_class_install_property(object_class,
 100                 PROP_CONSTRAIN,
 101                 g_param_spec_boolean("constrain",
 102                         "Constrain",
 103                         "Try not to place the side beyond the body's edges.",
 104                         FALSE,
 105                         G_PARAM_READWRITE));
 106         gtk_container_class_install_child_property(container_class,
 107                 CHILD_PROP_ALIGN,
 108                 g_param_spec_float("align",
 109                         "Alignment",
 110                         "Alignment of the child within the available space.",
 111                         0.0, 1.0, 0.5,
 112                         G_PARAM_READWRITE));
 113 }
 114
 115 GtkWidget *aspect_bin_new(void)
 116 {
 117         return GTK_WIDGET(g_object_new(ASPECT_BIN_TYPE, NULL));
 118 }
 119
 120 static void aspect_bin_set_property(GObject      *object,
 121                                     guint         prop_id,
 122                                     const GValue *value,
 123                                     GParamSpec   *pspec)
 124 {
 125         AspectBin *abin = ASPECT_BIN(object);
 126         gfloat tmp;
 127
 128         switch (prop_id) {
 129         case PROP_RATIO:
 130                 tmp = abin->ratio;
 131                 abin->ratio = g_value_get_float(value);
 132                 if (tmp != abin->ratio)
 133                         gtk_widget_queue_resize(GTK_WIDGET(abin));
 134                 break;
 135         case PROP_CONSTRAIN:
 136                 abin->constrain = g_value_get_boolean(value);
 137                 gtk_widget_queue_resize(GTK_WIDGET(abin));
 138                 break;
 139         case PROP_FILL:
 140                 abin->fill = g_value_get_boolean(value);
 141                 gtk_widget_queue_resize(GTK_WIDGET(abin));
 142                 break;
 143         default:
 144                 G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
 145         }
 146 }
 147
 148 static void aspect_bin_get_property(GObject    *object,
 149                                     guint       prop_id,
 150                                     GValue     *value,
 151                                     GParamSpec *pspec)
 152 {
 153         AspectBin *abin = ASPECT_BIN(object);
 154
 155         switch (prop_id) {
 156         case PROP_RATIO:
 157                 g_value_set_float(value, abin->ratio);
 158                 break;
 159         case PROP_CONSTRAIN:
 160                 g_value_set_boolean(value, abin->constrain);
 161                 break;
 162         case PROP_FILL:
 163                 g_value_set_boolean(value, abin->fill);
 164                 break;
 165         default:
 166                 G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
 167         }
 168 }
 169
 170 static void aspect_bin_set_child_property(GtkContainer *container,
 171                                           GtkWidget    *child,
 172                                           guint         prop_id,
 173                                           const GValue *value,
 174                                           GParamSpec   *pspec)
 175 {
 176         AspectBin *abin = ASPECT_BIN(container);
 177         gfloat align;
 178
 179         g_assert(child == abin->body || child == abin->side);
 180
 181         switch (prop_id) {
 182         case CHILD_PROP_ALIGN:
 183                 align = g_value_get_float(value);
 184                 if (child == abin->body)
 185                         abin->body_align = align;
 186                 else if (child == abin->side)
 187                         abin->side_align = align;
 188                 gtk_widget_queue_resize(GTK_WIDGET(abin));
 189                 break;
 190         default:
 191                 GTK_CONTAINER_WARN_INVALID_CHILD_PROPERTY_ID(container,
 192                                                              prop_id, pspec);
 193         }
 194 }
 195
 196 static void aspect_bin_get_child_property(GtkContainer *container,
 197                                           GtkWidget    *child,
 198                                           guint         prop_id,
 199                                           GValue       *value,
 200                                           GParamSpec   *pspec)
 201 {
 202         AspectBin *abin = ASPECT_BIN(container);
 203         gfloat align = 0;
 204
 205         g_assert(child == abin->body || child == abin->side);
 206
 207         switch (prop_id) {
 208         case CHILD_PROP_ALIGN:
 209                 if (child == abin->body)
 210                         align = abin->body_align;
 211                 else if (child == abin->side)
 212                         align = abin->side_align;
 213                 g_value_set_float(value, align);
 214                 break;
 215         default:
 216                 GTK_CONTAINER_WARN_INVALID_CHILD_PROPERTY_ID(container,
 217                                                              prop_id, pspec);
 218         }
 219 }
 220
 221 static void aspect_bin_add(GtkContainer *container, GtkWidget *widget)
 222 {
 223         AspectBin *abin;
 224         g_return_if_fail(IS_ASPECT_BIN(container));
 225         abin = ASPECT_BIN(container);
 226
 227         if (!abin->body)
 228                 aspect_bin_set_body(abin, widget, 1);
 229         else if (!abin->side)
 230                 aspect_bin_set_side(abin, widget);
 231         else
 232                 g_warning("AspectBin cannot have more than 2 children.\n");
 233 }
 234
 235 static void aspect_bin_remove(GtkContainer *container, GtkWidget *child)
 236 {
 237         AspectBin *abin = ASPECT_BIN(container);
 238
 239         if (abin->body == child) {
 240                 aspect_bin_set_body(abin, NULL, 1);
 241         } else if (abin->side == child) {
 242                 aspect_bin_set_side(abin, NULL);
 243         }
 244 }
 245
 246 static void aspect_bin_forall(GtkContainer *container,
 247                               gboolean      include_internals,
 248                               GtkCallback   callback,
 249                               gpointer      callback_data)
 250 {
 251         AspectBin *abin = ASPECT_BIN(container);
 252         g_return_if_fail(callback != NULL);
 253
 254         if (abin->body)
 255                 callback(abin->body, callback_data);
 256         if (abin->side)
 257                 callback(abin->side, callback_data);
 258 }
 259
 260 static GType aspect_bin_child_type(GtkContainer *container)
 261 {
 262         if (!ASPECT_BIN(container)->body || !ASPECT_BIN(container)->side)
 263                 return GTK_TYPE_WIDGET;
 264         return G_TYPE_NONE;
 265 }
 266
 267 static void
 268 aspect_bin_size_request(GtkWidget *widget, GtkRequisition *requisition)
 269 {
 270         AspectBin *abin = ASPECT_BIN(widget);
 271         GtkRequisition creq = {0}, areq = {0};
 272
 273         if (abin->side && GTK_WIDGET_VISIBLE(abin->side)) {
 274                 gtk_widget_size_request(abin->side, &creq);
 275         }
 276
 277         if (abin->body && GTK_WIDGET_VISIBLE(abin->body)) {
 278                 int wtmp, htmp;
 279                 gtk_widget_size_request(abin->body, &areq);
 280                 wtmp = areq.height * abin->ratio + 0.5;
 281                 htmp = areq.width  / abin->ratio + 0.5;
 282
 283                 if (wtmp > areq.width) {
 284                         areq.width  = wtmp;
 285                 } else {
 286                         areq.height = htmp;
 287                 }
 288         }
 289
 290         requisition->width  = areq.width + creq.width;
 291         requisition->height = MAX(areq.height, creq.height);
 292 }
 293
 294 static void
 295 aspect_bin_size_allocate(GtkWidget *widget, GtkAllocation *allocation)
 296 {
 297         AspectBin *abin = ASPECT_BIN(widget);
 298         GtkRequisition creq = {0};
 299         GtkAllocation csize = {0}, asize = {0};
 300
 301         /* First find the best fit for the body. */
 302         if (abin->body && GTK_WIDGET_VISIBLE(abin->body)) {
 303                 asize.height = allocation->height;
 304                 asize.width  = asize.height * abin->ratio + 0.5;
 305
 306                 if (asize.width > allocation->width) {
 307                         asize.width  = allocation->width;
 308                         asize.height = asize.width / abin->ratio + 0.5;
 309                 }
 310         }
 311
 312         /* Now try to fit the side. */
 313         if (abin->side && GTK_WIDGET_VISIBLE(abin->side)) {
 314                 gtk_widget_get_child_requisition(abin->side, &creq);
 315
 316                 if (allocation->width - asize.width < creq.width) {
 317                         /* It didn't fit, squish the constrained guy. */
 318                         asize.width  = allocation->width - creq.width;
 319                         asize.height = asize.width / abin->ratio + 0.5;
 320                 }
 321
 322                 csize.width  = allocation->width - asize.width;
 323                 csize.x = asize.width;
 324
 325                 if (abin->fill && abin->constrain) {
 326                         csize.height = asize.height;
 327                 } else if (abin->fill) {
 328                         csize.height = allocation->height;
 329                 } else {
 330                         csize.height = MIN(creq.height, allocation->height);
 331                 }
 332         }
 333
 334         asize.y = (allocation->height - asize.height) * abin->body_align + 0.5;
 335
 336         if (abin->constrain && csize.height <= asize.height) {
 337                 csize.y = asize.y + (asize.height-csize.height)
 338                         * abin->side_align + 0.5;
 339         } else if (abin->constrain) {
 340                 csize.y = (allocation->height - csize.height)
 341                         * abin->body_align + 0.5;
 342         } else {
 343                 csize.y = (allocation->height - csize.height)
 344                         * abin->side_align + 0.5;
 345         }
 346
 347         if (abin->body)
 348                 gtk_widget_size_allocate(abin->body, &asize);
 349         if (abin->side)
 350                 gtk_widget_size_allocate(abin->side, &csize);
 351 }
 352
 353 static gboolean
 354 set_widget(GtkWidget **dest, GtkWidget *parent, GtkWidget *widget)
 355 {
 356         gboolean need_resize = FALSE;
 357
 358         if (*dest == widget)
 359                 return FALSE;
 360
 361         if (*dest) {
 362                 need_resize |= GTK_WIDGET_VISIBLE(*dest);
 363                 gtk_widget_unparent(*dest);
 364         }
 365
 366         *dest = widget;
 367         if (widget) {
 368                 gtk_widget_set_parent(widget, parent);
 369                 need_resize |= GTK_WIDGET_VISIBLE(widget);
 370         }
 371
 372         return GTK_WIDGET_VISIBLE(parent) && need_resize;
 373 }
 374
 375 void aspect_bin_set_body(AspectBin *abin, GtkWidget *widget, gfloat ratio)
 376 {
 377         g_return_if_fail(IS_ASPECT_BIN(abin));
 378         g_return_if_fail(widget == NULL || GTK_IS_WIDGET(widget));
 379         g_return_if_fail(widget == NULL || widget->parent == NULL);
 380
 381         if (set_widget(&abin->body, GTK_WIDGET(abin), widget))
 382                 gtk_widget_queue_resize(GTK_WIDGET(abin));
 383 }
 384
 385 void aspect_bin_set_side(AspectBin *abin, GtkWidget *widget)
 386 {
 387         g_return_if_fail(IS_ASPECT_BIN(abin));
 388         g_return_if_fail(widget == NULL || GTK_IS_WIDGET(widget));
 389         g_return_if_fail(widget == NULL || widget->parent == NULL);
 390
 391         if (set_widget(&abin->side, GTK_WIDGET(abin), widget))
 392                 gtk_widget_queue_resize(GTK_WIDGET(abin));
 393 }
 394
 395 GtkWidget *aspect_bin_get_body(AspectBin *abin)
 396 {
 397         g_return_val_if_fail(IS_ASPECT_BIN(abin), NULL);
 398         return abin->body;
 399 }
 400
 401 GtkWidget *aspect_bin_get_side(AspectBin *abin)
 402 {
 403         g_return_val_if_fail(IS_ASPECT_BIN(abin), NULL);
 404         return abin->side;
 405 }