src/gtk-tpdfv.c

   1 /*
   2  * tpdfview - src/gtk-tpdfv.c
   3  * Copyright (C) 2011 Sebastian 'tokkee' Harl <sh@tokkee.org>
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  16  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  17  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  18  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR
  19  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  20  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  21  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  22  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  23  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  24  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  25  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 /*
  29  * This module provides a Gtk widget to display PDF files.
  30  */
  31
  32 #include "gtk-tpdfv.h"
  33
  34 #include <assert.h>
  35
  36 #include <errno.h>
  37
  38 #include <cairo.h>
  39 #include <gtk/gtk.h>
  40
  41 #include <poppler.h>
  42
  43 #include <stdlib.h>
  44 #include <string.h>
  45
  46 #define TPDFV_MIN(a, b) ((a) <= (b) ? (a) : (b))
  47 #define TPDFV_MAX(a, b) ((a) >= (b) ? (a) : (b))
  48
  49 typedef enum {
  50         TPDFV_ZOOM_CUSTOM = 0,
  51         TPDFV_ZOOM_WIDTH,
  52         TPDFV_ZOOM_HEIGHT,
  53         TPDFV_ZOOM_FIT,
  54 } tpdfv_zoommode_t;
  55
  56 typedef struct {
  57         char *filename;
  58
  59         PopplerDocument *doc;
  60         PopplerPage     *current_page;
  61
  62         int current_page_no;
  63         int total_pages;
  64
  65         tpdfv_zoommode_t zoom_mode;
  66         double zoom_factor;
  67
  68         double delta_x;
  69         double delta_y;
  70 } gtk_tpdfv_t;
  71
  72 GType gtk_tpdfv_get_type(void);
  73 G_DEFINE_TYPE(GtkTPDFV, gtk_tpdfv, GTK_TYPE_DRAWING_AREA);
  74
  75 #define GTK_TPDFV_GET_PRIVATE(obj) \
  76         (G_TYPE_INSTANCE_GET_PRIVATE ((obj), GTK_TYPE_TPDFV, gtk_tpdfv_t))
  77
  78 /*
  79  * Private helper functions.
  80  */
  81
  82 static void
  83 tpdfv_open(gtk_tpdfv_t *pdf)
  84 {
  85         GError *err = NULL;
  86
  87         if ((! pdf) || (! pdf->filename))
  88                 return;
  89
  90         pdf->doc = poppler_document_new_from_file(pdf->filename,
  91                         /* password = */ NULL, &err);
  92         if (! pdf->doc) {
  93                 fprintf(stderr, "Failed to open PDF: %s.\n", err->message);
  94                 return;
  95         }
  96
  97         pdf->total_pages = poppler_document_get_n_pages(pdf->doc);
  98         if (pdf->current_page_no >= pdf->total_pages)
  99                 pdf->current_page_no = pdf->total_pages - 1;
 100 } /* tpdfv_open */
 101
 102 static void
 103 tpdfv_close(gtk_tpdfv_t *pdf)
 104 {
 105         if (! pdf)
 106                 return;
 107
 108         g_object_unref(pdf->doc);
 109         pdf->doc = NULL;
 110         pdf->current_page = NULL;
 111 } /* tpdfv_close */
 112
 113 static gboolean
 114 tpdfv_init(gtk_tpdfv_t *pdf, const char *filename)
 115 {
 116         if (strstr(filename, "://"))
 117                 pdf->filename = strdup(filename);
 118         else {
 119                 size_t len = strlen("file://") + strlen(filename);
 120                 pdf->filename = (char *)malloc(len + 1);
 121                 if (pdf->filename) {
 122                         *pdf->filename = '\0';
 123                         strncat(pdf->filename, "file://", len);
 124                         strncat(pdf->filename, filename, len - strlen("file://"));
 125                 }
 126         }
 127
 128         /* XXX: error reporting mechanism */
 129
 130         if (! pdf->filename) {
 131                 char errbuf[1024];
 132                 strerror_r(errno, errbuf, sizeof(errbuf));
 133                 fprintf(stderr, "Failed to allocate string: %s.\n", errbuf);
 134                 return FALSE;
 135         }
 136
 137         pdf->doc = NULL;
 138         tpdfv_open(pdf);
 139
 140         pdf->current_page_no = 0;
 141         pdf->current_page = poppler_document_get_page(pdf->doc,
 142                         pdf->current_page_no);
 143         if (! pdf->current_page) {
 144                 fprintf(stderr, "Failed to open first page of the document.\n");
 145                 return FALSE;
 146         }
 147
 148         pdf->zoom_mode   = TPDFV_ZOOM_CUSTOM;
 149         pdf->zoom_factor = 1.0;
 150         pdf->delta_x = pdf->delta_y = 0.0;
 151         return TRUE;
 152 } /* tpdfv_init */
 153
 154 static void
 155 tpdfv_clean(gtk_tpdfv_t *pdf)
 156 {
 157         if (! pdf)
 158                 return;
 159
 160         tpdfv_close(pdf);
 161         pdf->current_page = NULL;
 162         free(pdf->filename);
 163         pdf->filename = NULL;
 164         return;
 165 } /* tpdfv_clean */
 166
 167 static void
 168 do_redraw(GtkWidget *widget)
 169 {
 170         GdkRegion *region;
 171         gtk_tpdfv_t *pdf;
 172
 173         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 174
 175         if ((! pdf->current_page) || (poppler_page_get_index(pdf->current_page)
 176                         != pdf->current_page_no)) {
 177                 pdf->current_page = poppler_document_get_page(pdf->doc,
 178                 pdf->current_page_no);
 179
 180                 if (! pdf->current_page) {
 181                         fprintf(stderr, "Failed to open page %i of the document.\n",
 182                                         pdf->current_page_no + 1);
 183                         return;
 184                 }
 185         }
 186
 187         region = gdk_drawable_get_clip_region(widget->window);
 188         gdk_window_invalidate_region(widget->window, region, TRUE);
 189         gdk_window_process_updates(widget->window, TRUE);
 190
 191         gdk_region_destroy(region);
 192 } /* do_redraw */
 193
 194 /*
 195  * Gtk+ class definition.
 196  */
 197
 198 static gboolean
 199 gtk_tpdfv_expose(GtkWidget *tpdfv, GdkEventExpose *event)
 200 {
 201         gtk_tpdfv_t *pdf;
 202         cairo_t *cr;
 203
 204         gdouble width, height;
 205
 206         gdouble page_width  = 0.0;
 207         gdouble page_height = 0.0;
 208
 209         double zoom_factor  = 1.0;
 210         double x, y;
 211
 212         pdf = GTK_TPDFV_GET_PRIVATE(tpdfv);
 213
 214         if (! pdf)
 215                 return FALSE;
 216
 217         cr = gdk_cairo_create(tpdfv->window);
 218         cairo_rectangle(cr, event->area.x, event->area.y,
 219                         event->area.width, event->area.height);
 220         cairo_clip(cr);
 221
 222         poppler_page_get_size(pdf->current_page, &page_width, &page_height);
 223         width  = (gdouble)tpdfv->allocation.width;
 224         height = (gdouble)tpdfv->allocation.height;
 225
 226         /* zoom */
 227         if (pdf->zoom_mode == TPDFV_ZOOM_CUSTOM) {
 228                 zoom_factor = pdf->zoom_factor;
 229         }
 230         else {
 231                 if (pdf->zoom_mode == TPDFV_ZOOM_WIDTH) {
 232                         zoom_factor = (double)(width / page_width);
 233                 }
 234                 else if (pdf->zoom_mode == TPDFV_ZOOM_HEIGHT) {
 235                         zoom_factor = (double)(height / page_height);
 236                 }
 237                 else if (pdf->zoom_mode == TPDFV_ZOOM_FIT) {
 238                         zoom_factor = (double)TPDFV_MIN(width / page_width,
 239                                         height / page_height);
 240                 }
 241                 else {
 242                         assert(0);
 243                 }
 244         }
 245         cairo_scale(cr, zoom_factor, zoom_factor);
 246
 247         /* centered position / scrolling */
 248         x = (double)(width - page_width * zoom_factor) / 2.0 / zoom_factor;
 249         y = (double)(height - page_height * zoom_factor) / 2.0 / zoom_factor;
 250
 251         cairo_translate(cr, x + pdf->delta_x, y + pdf->delta_y);
 252
 253         poppler_page_render(pdf->current_page, cr);
 254
 255         cairo_destroy(cr);
 256         return FALSE;
 257 } /* gtk_tpdfv_expose */
 258
 259 static void
 260 gtk_tpdfv_destroy(GtkObject *obj)
 261 {
 262         GtkTPDFV    *tpdfv = GTK_TPDFV(obj);
 263         gtk_tpdfv_t *pdf;
 264
 265         pdf = GTK_TPDFV_GET_PRIVATE(tpdfv);
 266         tpdfv_clean(pdf);
 267
 268         GTK_OBJECT_CLASS(gtk_tpdfv_parent_class)->destroy(obj);
 269 } /* gtk_tpdfv_destroy */
 270
 271 static void
 272 gtk_tpdfv_class_init(GtkTPDFVClass *class)
 273 {
 274         GObjectClass   *goclass;
 275         GtkObjectClass *oclass;
 276         GtkWidgetClass *wclass;
 277
 278         goclass = G_OBJECT_CLASS(class);
 279         g_type_class_add_private(goclass, sizeof(gtk_tpdfv_t));
 280
 281         oclass = GTK_OBJECT_CLASS(class);
 282         oclass->destroy = gtk_tpdfv_destroy;
 283
 284         wclass = GTK_WIDGET_CLASS(class);
 285         wclass->expose_event = gtk_tpdfv_expose;
 286 } /* gtk_tpdfv_class_init */
 287
 288 static void
 289 gtk_tpdfv_init(GtkTPDFV __attribute__((unused)) *tpdfv)
 290 {
 291         /* nothing to do for now */
 292 } /* gtk_tpdfv_init */
 293
 294 /*
 295  * Public API.
 296  */
 297
 298 GtkWidget *
 299 gtk_tpdfv_new(const char *filename)
 300 {
 301         GtkTPDFV    *tpdfv;
 302         gtk_tpdfv_t *pdf;
 303
 304         tpdfv = g_object_new(GTK_TYPE_TPDFV, NULL);
 305         pdf   = GTK_TPDFV_GET_PRIVATE(tpdfv);
 306
 307         if (TRUE != tpdfv_init(pdf, filename))
 308                 return NULL;
 309         return GTK_WIDGET(tpdfv);
 310 } /* gtk_tpdfv_new */
 311
 312 void
 313 gtk_tpdfv_reload(GtkWidget *widget)
 314 {
 315         gtk_tpdfv_t *pdf;
 316
 317         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 318         tpdfv_close(pdf);
 319         tpdfv_open(pdf);
 320         do_redraw(widget);
 321 } /* gtk_tpdfv_reload */
 322
 323 void
 324 gtk_tpdfv_page_up(GtkWidget *widget)
 325 {
 326         gtk_tpdfv_t *pdf;
 327
 328         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 329
 330         if (pdf->current_page_no)
 331                 --pdf->current_page_no;
 332         do_redraw(widget);
 333 } /* gtk_tpdfv_page_up */
 334
 335 void
 336 gtk_tpdfv_page_down(GtkWidget *widget)
 337 {
 338         gtk_tpdfv_t *pdf;
 339
 340         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 341
 342         if (pdf->current_page_no < pdf->total_pages - 1)
 343                 ++pdf->current_page_no;
 344         do_redraw(widget);
 345 } /* gtk_tpdfv_page_down */
 346
 347 void
 348 gtk_tpdfv_first_page(GtkWidget *widget)
 349 {
 350         gtk_tpdfv_t *pdf;
 351
 352         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 353         pdf->current_page_no = 0;
 354         do_redraw(widget);
 355 } /* gtk_tpdfv_first_page */
 356
 357 void
 358 gtk_tpdfv_last_page(GtkWidget *widget)
 359 {
 360         gtk_tpdfv_t *pdf;
 361
 362         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 363         pdf->current_page_no = pdf->total_pages - 1;
 364         do_redraw(widget);
 365 } /* gtk_tpdfv_last_page */
 366
 367 void
 368 gtk_tpdfv_zoom_in(GtkWidget *widget)
 369 {
 370         gtk_tpdfv_t *pdf;
 371
 372         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 373         pdf->zoom_factor *= 1.2;
 374         pdf->zoom_mode    = TPDFV_ZOOM_CUSTOM;
 375         do_redraw(widget);
 376 } /* gtk_tpdfv_zoom_in */
 377
 378 void
 379 gtk_tpdfv_zoom_out(GtkWidget *widget)
 380 {
 381         gtk_tpdfv_t *pdf;
 382
 383         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 384
 385         if (pdf->zoom_factor > DBL_EPSILON * 2.0) {
 386                 pdf->zoom_factor /= 1.2;
 387                 pdf->zoom_mode    = TPDFV_ZOOM_CUSTOM;
 388                 do_redraw(widget);
 389         }
 390 } /* gtk_tpdfv_zoom_out */
 391
 392 void
 393 gtk_tpdfv_zoom_1(GtkWidget *widget)
 394 {
 395         gtk_tpdfv_t *pdf;
 396
 397         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 398         pdf->zoom_factor = 1.0;
 399         pdf->zoom_mode   = TPDFV_ZOOM_CUSTOM;
 400         do_redraw(widget);
 401 } /* gtk_tpdfv_zoom_1 */
 402
 403 void
 404 gtk_tpdfv_zoom_width(GtkWidget *widget)
 405 {
 406         gtk_tpdfv_t *pdf;
 407
 408         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 409         pdf->zoom_mode = TPDFV_ZOOM_WIDTH;
 410         do_redraw(widget);
 411 } /* gtk_tpdfv_zoom_width */
 412
 413 void
 414 gtk_tpdfv_zoom_height(GtkWidget *widget)
 415 {
 416         gtk_tpdfv_t *pdf;
 417
 418         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 419         pdf->zoom_mode = TPDFV_ZOOM_HEIGHT;
 420         do_redraw(widget);
 421 } /* gtk_tpdfv_zoom_width */
 422
 423 void
 424 gtk_tpdfv_zoom_fit(GtkWidget *widget)
 425 {
 426         gtk_tpdfv_t *pdf;
 427
 428         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 429         pdf->zoom_mode = TPDFV_ZOOM_FIT;
 430         do_redraw(widget);
 431 } /* gtk_tpdfv_zoom_width */
 432
 433 void
 434 gtk_tpdfv_scroll_up(GtkWidget *widget)
 435 {
 436         gtk_tpdfv_t *pdf;
 437
 438         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 439         pdf->delta_y += 10.0;
 440         do_redraw(widget);
 441 } /* gtk_tpdfv_scroll_up */
 442
 443 void
 444 gtk_tpdfv_scroll_down(GtkWidget *widget)
 445 {
 446         gtk_tpdfv_t *pdf;
 447
 448         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 449         pdf->delta_y -= 10.0;
 450         do_redraw(widget);
 451 } /* gtk_tpdfv_scroll_down */
 452
 453 void
 454 gtk_tpdfv_scroll_left(GtkWidget *widget)
 455 {
 456         gtk_tpdfv_t *pdf;
 457
 458         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 459         pdf->delta_x += 10.0;
 460         do_redraw(widget);
 461 } /* gtk_tpdfv_scroll_left */
 462
 463 void
 464 gtk_tpdfv_scroll_right(GtkWidget *widget)
 465 {
 466         gtk_tpdfv_t *pdf;
 467
 468         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 469         pdf->delta_x -= 10.0;
 470         do_redraw(widget);
 471 } /* gtk_tpdfv_scroll_right */
 472
 473 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 474