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 gboolean
  83 tpdfv_init(gtk_tpdfv_t *pdf, const char *filename)
  84 {
  85         GError *err = NULL;
  86
  87         if (strstr(filename, "://"))
  88                 pdf->filename = strdup(filename);
  89         else {
  90                 size_t len = strlen("file://") + strlen(filename);
  91                 pdf->filename = (char *)malloc(len + 1);
  92                 if (pdf->filename) {
  93                         *pdf->filename = '\0';
  94                         strncat(pdf->filename, "file://", len);
  95                         strncat(pdf->filename, filename, len - strlen("file://"));
  96                 }
  97         }
  98
  99         /* XXX: error reporting mechanism */
 100
 101         if (! pdf->filename) {
 102                 char errbuf[1024];
 103                 strerror_r(errno, errbuf, sizeof(errbuf));
 104                 fprintf(stderr, "Failed to allocate string: %s.\n", errbuf);
 105                 return FALSE;
 106         }
 107
 108         pdf->doc = poppler_document_new_from_file(pdf->filename,
 109                         /* password = */ NULL, &err);
 110         if (! pdf->doc) {
 111                 fprintf(stderr, "Failed to open PDF: %s.\n", err->message);
 112                 return FALSE;
 113         }
 114
 115         pdf->current_page_no = 0;
 116         pdf->current_page = poppler_document_get_page(pdf->doc,
 117                         pdf->current_page_no);
 118         if (! pdf->current_page) {
 119                 fprintf(stderr, "Failed to open first page of the document.\n");
 120                 return FALSE;
 121         }
 122
 123         pdf->total_pages = poppler_document_get_n_pages(pdf->doc);
 124
 125         pdf->zoom_mode   = TPDFV_ZOOM_CUSTOM;
 126         pdf->zoom_factor = 1.0;
 127         pdf->delta_x = pdf->delta_y = 0.0;
 128         return TRUE;
 129 } /* tpdfv_init */
 130
 131 static void
 132 tpdfv_clean(gtk_tpdfv_t *pdf)
 133 {
 134         if (! pdf)
 135                 return;
 136
 137         g_object_unref(pdf->doc);
 138         pdf->doc          = NULL;
 139         pdf->current_page = NULL;
 140         free(pdf->filename);
 141         pdf->filename = NULL;
 142         return;
 143 } /* tpdfv_clean */
 144
 145 static void
 146 do_redraw(GtkWidget *widget)
 147 {
 148         GdkRegion *region;
 149         gtk_tpdfv_t *pdf;
 150
 151         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 152
 153         if (poppler_page_get_index(pdf->current_page)
 154                         != pdf->current_page_no) {
 155                 pdf->current_page = poppler_document_get_page(pdf->doc,
 156                 pdf->current_page_no);
 157
 158                 if (! pdf->current_page) {
 159                         fprintf(stderr, "Failed to open page %i of the document.\n",
 160                                         pdf->current_page_no + 1);
 161                         return;
 162                 }
 163         }
 164
 165         region = gdk_drawable_get_clip_region(widget->window);
 166         gdk_window_invalidate_region(widget->window, region, TRUE);
 167         gdk_window_process_updates(widget->window, TRUE);
 168
 169         gdk_region_destroy(region);
 170 } /* do_redraw */
 171
 172 /*
 173  * Gtk+ class definition.
 174  */
 175
 176 static gboolean
 177 gtk_tpdfv_expose(GtkWidget *tpdfv, GdkEventExpose *event)
 178 {
 179         gtk_tpdfv_t *pdf;
 180         cairo_t *cr;
 181
 182         gdouble width, height;
 183
 184         gdouble page_width  = 0.0;
 185         gdouble page_height = 0.0;
 186
 187         double zoom_factor  = 1.0;
 188         double x, y;
 189
 190         pdf = GTK_TPDFV_GET_PRIVATE(tpdfv);
 191
 192         if (! pdf)
 193                 return FALSE;
 194
 195         cr = gdk_cairo_create(tpdfv->window);
 196         cairo_rectangle(cr, event->area.x, event->area.y,
 197                         event->area.width, event->area.height);
 198         cairo_clip(cr);
 199
 200         poppler_page_get_size(pdf->current_page, &page_width, &page_height);
 201         width  = (gdouble)tpdfv->allocation.width;
 202         height = (gdouble)tpdfv->allocation.height;
 203
 204         /* zoom */
 205         if (pdf->zoom_mode == TPDFV_ZOOM_CUSTOM) {
 206                 zoom_factor = pdf->zoom_factor;
 207         }
 208         else {
 209                 if (pdf->zoom_mode == TPDFV_ZOOM_WIDTH) {
 210                         zoom_factor = (double)(width / page_width);
 211                 }
 212                 else if (pdf->zoom_mode == TPDFV_ZOOM_HEIGHT) {
 213                         zoom_factor = (double)(height / page_height);
 214                 }
 215                 else if (pdf->zoom_mode == TPDFV_ZOOM_FIT) {
 216                         zoom_factor = (double)TPDFV_MIN(width / page_width,
 217                                         height / page_height);
 218                 }
 219                 else {
 220                         assert(0);
 221                 }
 222         }
 223         cairo_scale(cr, zoom_factor, zoom_factor);
 224
 225         /* centered position / scrolling */
 226         x = (double)(width - page_width * zoom_factor) / 2.0 / zoom_factor;
 227         y = (double)(height - page_height * zoom_factor) / 2.0 / zoom_factor;
 228
 229         cairo_translate(cr, x + pdf->delta_x, y + pdf->delta_y);
 230
 231         poppler_page_render(pdf->current_page, cr);
 232
 233         cairo_destroy(cr);
 234         return FALSE;
 235 } /* gtk_tpdfv_expose */
 236
 237 static void
 238 gtk_tpdfv_destroy(GtkObject *obj)
 239 {
 240         GtkTPDFV    *tpdfv = GTK_TPDFV(obj);
 241         gtk_tpdfv_t *pdf;
 242
 243         pdf = GTK_TPDFV_GET_PRIVATE(tpdfv);
 244         tpdfv_clean(pdf);
 245
 246         GTK_OBJECT_CLASS(gtk_tpdfv_parent_class)->destroy(obj);
 247 } /* gtk_tpdfv_destroy */
 248
 249 static void
 250 gtk_tpdfv_class_init(GtkTPDFVClass *class)
 251 {
 252         GObjectClass   *goclass;
 253         GtkObjectClass *oclass;
 254         GtkWidgetClass *wclass;
 255
 256         goclass = G_OBJECT_CLASS(class);
 257         g_type_class_add_private(goclass, sizeof(gtk_tpdfv_t));
 258
 259         oclass = GTK_OBJECT_CLASS(class);
 260         oclass->destroy = gtk_tpdfv_destroy;
 261
 262         wclass = GTK_WIDGET_CLASS(class);
 263         wclass->expose_event = gtk_tpdfv_expose;
 264 } /* gtk_tpdfv_class_init */
 265
 266 static void
 267 gtk_tpdfv_init(GtkTPDFV __attribute__((unused)) *tpdfv)
 268 {
 269         /* nothing to do for now */
 270 } /* gtk_tpdfv_init */
 271
 272 /*
 273  * Public API.
 274  */
 275
 276 GtkWidget *
 277 gtk_tpdfv_new(const char *filename)
 278 {
 279         GtkTPDFV    *tpdfv;
 280         gtk_tpdfv_t *pdf;
 281
 282         tpdfv = g_object_new(GTK_TYPE_TPDFV, NULL);
 283         pdf   = GTK_TPDFV_GET_PRIVATE(tpdfv);
 284
 285         if (TRUE != tpdfv_init(pdf, filename))
 286                 return NULL;
 287         return GTK_WIDGET(tpdfv);
 288 } /* gtk_tpdfv_new */
 289
 290 void
 291 gtk_tpdfv_page_up(GtkWidget *widget)
 292 {
 293         gtk_tpdfv_t *pdf;
 294
 295         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 296
 297         if (pdf->current_page_no)
 298                 --pdf->current_page_no;
 299         do_redraw(widget);
 300 } /* gtk_tpdfv_page_up */
 301
 302 void
 303 gtk_tpdfv_page_down(GtkWidget *widget)
 304 {
 305         gtk_tpdfv_t *pdf;
 306
 307         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 308
 309         if (pdf->current_page_no < pdf->total_pages - 1)
 310                 ++pdf->current_page_no;
 311         do_redraw(widget);
 312 } /* gtk_tpdfv_page_down */
 313
 314 void
 315 gtk_tpdfv_first_page(GtkWidget *widget)
 316 {
 317         gtk_tpdfv_t *pdf;
 318
 319         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 320         pdf->current_page_no = 0;
 321         do_redraw(widget);
 322 } /* gtk_tpdfv_first_page */
 323
 324 void
 325 gtk_tpdfv_last_page(GtkWidget *widget)
 326 {
 327         gtk_tpdfv_t *pdf;
 328
 329         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 330         pdf->current_page_no = pdf->total_pages - 1;
 331         do_redraw(widget);
 332 } /* gtk_tpdfv_last_page */
 333
 334 void
 335 gtk_tpdfv_zoom_in(GtkWidget *widget)
 336 {
 337         gtk_tpdfv_t *pdf;
 338
 339         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 340         pdf->zoom_factor *= 1.2;
 341         pdf->zoom_mode    = TPDFV_ZOOM_CUSTOM;
 342         do_redraw(widget);
 343 } /* gtk_tpdfv_zoom_in */
 344
 345 void
 346 gtk_tpdfv_zoom_out(GtkWidget *widget)
 347 {
 348         gtk_tpdfv_t *pdf;
 349
 350         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 351
 352         if (pdf->zoom_factor > DBL_EPSILON * 2.0) {
 353                 pdf->zoom_factor /= 1.2;
 354                 pdf->zoom_mode    = TPDFV_ZOOM_CUSTOM;
 355                 do_redraw(widget);
 356         }
 357 } /* gtk_tpdfv_zoom_out */
 358
 359 void
 360 gtk_tpdfv_zoom_1(GtkWidget *widget)
 361 {
 362         gtk_tpdfv_t *pdf;
 363
 364         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 365         pdf->zoom_factor = 1.0;
 366         pdf->zoom_mode   = TPDFV_ZOOM_CUSTOM;
 367         do_redraw(widget);
 368 } /* gtk_tpdfv_zoom_1 */
 369
 370 void
 371 gtk_tpdfv_zoom_width(GtkWidget *widget)
 372 {
 373         gtk_tpdfv_t *pdf;
 374
 375         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 376         pdf->zoom_mode = TPDFV_ZOOM_WIDTH;
 377         do_redraw(widget);
 378 } /* gtk_tpdfv_zoom_width */
 379
 380 void
 381 gtk_tpdfv_zoom_height(GtkWidget *widget)
 382 {
 383         gtk_tpdfv_t *pdf;
 384
 385         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 386         pdf->zoom_mode = TPDFV_ZOOM_HEIGHT;
 387         do_redraw(widget);
 388 } /* gtk_tpdfv_zoom_width */
 389
 390 void
 391 gtk_tpdfv_zoom_fit(GtkWidget *widget)
 392 {
 393         gtk_tpdfv_t *pdf;
 394
 395         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 396         pdf->zoom_mode = TPDFV_ZOOM_FIT;
 397         do_redraw(widget);
 398 } /* gtk_tpdfv_zoom_width */
 399
 400 void
 401 gtk_tpdfv_scroll_up(GtkWidget *widget)
 402 {
 403         gtk_tpdfv_t *pdf;
 404
 405         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 406         pdf->delta_y += 10.0;
 407         do_redraw(widget);
 408 } /* gtk_tpdfv_scroll_up */
 409
 410 void
 411 gtk_tpdfv_scroll_down(GtkWidget *widget)
 412 {
 413         gtk_tpdfv_t *pdf;
 414
 415         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 416         pdf->delta_y -= 10.0;
 417         do_redraw(widget);
 418 } /* gtk_tpdfv_scroll_down */
 419
 420 void
 421 gtk_tpdfv_scroll_left(GtkWidget *widget)
 422 {
 423         gtk_tpdfv_t *pdf;
 424
 425         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 426         pdf->delta_x += 10.0;
 427         do_redraw(widget);
 428 } /* gtk_tpdfv_scroll_left */
 429
 430 void
 431 gtk_tpdfv_scroll_right(GtkWidget *widget)
 432 {
 433         gtk_tpdfv_t *pdf;
 434
 435         pdf = GTK_TPDFV_GET_PRIVATE(widget);
 436         pdf->delta_x -= 10.0;
 437         do_redraw(widget);
 438 } /* gtk_tpdfv_scroll_right */
 439
 440 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 441