src/callbacks.c

   1 /*
   2  * This program is free software; you can redistribute it and/or
   3  * modify it under the terms of the GNU General Public License
   4  * as published by the Free Software Foundation; either version 2
   5  * of the License, or (at your option) any later version.
   6  *
   7  * This program is distributed in the hope that it will be useful,
   8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10  * GNU General Public License for more details.
  11  *
  12  * You should have received a copy of the GNU General Public License
  13  * along with this program; if not, write to the Free Software
  14  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  15  *
  16  * See the COPYING file for license information.
  17  *
  18  * Guillaume Chazarain <guichaz@yahoo.fr>
  19  */
  20
  21 /****************************************************************
  22  * Callbacks to control the gl_widget through its parent window *
  23  ****************************************************************/
  24
  25 #include <gdk/gdkkeysyms.h>     /* GDK_* */
  26
  27 #include "gliv.h"
  28 #include "callbacks.h"
  29 #include "math_floats.h"        /* atan2f(), powf() */
  30 #include "options.h"
  31 #include "rendering.h"
  32 #include "params.h"
  33 #include "main.h"
  34 #include "zoom_frame.h"
  35 #include "move_pointer.h"
  36 #include "matrix.h"
  37 #include "cursors.h"
  38 #include "next_image.h"
  39
  40 extern rt_struct *rt;
  41 extern options_struct *options;
  42 extern GtkWidget *gl_widget;
  43
  44 /* Left button saved position in the root window. */
  45 static gfloat old1_root_x, old1_root_y;
  46
  47 /* Where the left button press occured in the window. */
  48 static gfloat press1_win_x, press1_win_y;
  49
  50 /* Right button saved position in the window. */
  51 static gint old3_win_x, old3_win_y;
  52
  53 /* If the middle button is released. */
  54 static gboolean mouse_wheel_zoom = TRUE;
  55
  56 /* Number of times the pointer warped in each direction. */
  57 static gint nb_scr_w = 0, nb_scr_h = 0;
  58
  59 /* Absolute position, taking into account the screen warpings. */
  60 #define ROOT_X(e) ((e)->x_root + nb_scr_w * rt->scr_width)
  61 #define ROOT_Y(e) ((e)->y_root + nb_scr_h * rt->scr_height)
  62
  63 static gboolean button_press_event(GtkWidget * unused, GdkEventButton * event)
  64 {
  65     switch (event->button) {
  66     case 1:
  67         /* Reset mouse warping. */
  68         nb_scr_w = 0;
  69         nb_scr_h = 0;
  70
  71         old1_root_x = ROOT_X(event);
  72         old1_root_y = ROOT_Y(event);
  73
  74         press1_win_x = event->x;
  75         press1_win_y = event->y;
  76         break;
  77
  78     case 2:
  79         mouse_wheel_zoom = FALSE;
  80         break;
  81
  82     case 3:
  83         /* We now have one of the zoom rectangle vertex. */
  84         old3_win_x = (gint) event->x;
  85         old3_win_y = (gint) event->y;
  86         break;
  87     }
  88
  89     return FALSE;
  90 }
  91
  92 static gboolean button_release_event(GtkWidget * unused, GdkEventButton * event)
  93 {
  94     switch (event->button) {
  95     case 1:
  96         /* Reset mouse warping. */
  97         nb_scr_w = 0;
  98         nb_scr_h = 0;
  99
 100         refresh(APPEND_HISTORY);
 101         break;
 102
 103     case 2:
 104         mouse_wheel_zoom = TRUE;
 105         break;
 106
 107     case 3:
 108         zoom_frame();
 109     }
 110
 111     return FALSE;
 112 }
 113
 114 /* Checks whether the pointer is on a border then moves it and returns TRUE. */
 115 static gboolean warp_pointer(gfloat x, gfloat y)
 116 {
 117     gboolean warped;
 118     gint new_x, new_y;
 119
 120     if (x <= 0.0) {
 121         nb_scr_w--;
 122         new_x = rt->scr_width - 1;
 123         warped = TRUE;
 124
 125     } else if (x >= rt->scr_width - 1.0) {
 126         nb_scr_w++;
 127         new_x = 0;
 128         warped = TRUE;
 129
 130     } else {
 131         new_x = (gint) x;
 132         warped = FALSE;
 133     }
 134
 135     if (y <= 0.0) {
 136         nb_scr_h--;
 137         new_y = rt->scr_height - 1;
 138         warped = TRUE;
 139
 140     } else if (y >= rt->scr_height - 1.0) {
 141         nb_scr_h++;
 142         new_y = 0;
 143         warped = TRUE;
 144
 145     } else
 146         new_y = (gint) y;
 147
 148     if (warped)
 149         move_pointer(new_x, new_y);
 150
 151     return warped;
 152 }
 153
 154 /*
 155  * Remember the pointer position to know the sliding distance, the angle,
 156  * or the zoom when the first button is pressed.
 157  */
 158 static void update_coordinates1(GdkEventMotion * event)
 159 {
 160     old1_root_x = ROOT_X(event);
 161     old1_root_y = ROOT_Y(event);
 162 }
 163
 164 static gint process_move(GdkEventMotion * event)
 165 {
 166     gfloat root_x, root_y;
 167
 168     root_x = ROOT_X(event);
 169     root_y = ROOT_Y(event);
 170
 171     matrix_move(root_x - old1_root_x, root_y - old1_root_y);
 172
 173     return REFRESH_BURST;
 174 }
 175
 176 static gint process_rotation(GdkEventMotion * event)
 177 {
 178     gfloat center_x, center_y, x0, y0, x1, y1, angle;
 179     gint win_x, win_y;
 180
 181     gdk_window_get_root_origin(gl_widget->window, &win_x, &win_y);
 182
 183     /* Window center in root coordinates. */
 184     center_x = win_x + rt->wid_size->width / 2.0;
 185     center_y = win_y + rt->wid_size->height / 2.0;
 186
 187     /* First rotation vector. */
 188     x0 = old1_root_x - center_x;
 189     y0 = old1_root_y - center_y;
 190
 191     /* Second rotation vector. */
 192     x1 = ROOT_X(event) - center_x;
 193     y1 = ROOT_Y(event) - center_y;
 194
 195     angle = atan2f(y0, x0) + atan2f(x1, y1) - PI / 2.0;
 196
 197     matrix_rotate(angle);
 198
 199     return REFRESH_BURST | REFRESH_STATUS;
 200 }
 201
 202 static gint process_zoom(GdkEventMotion * event)
 203 {
 204     gfloat center_x, center_y, delta, ratio;
 205
 206     delta = ROOT_Y(event) - old1_root_y;
 207     ratio = powf(ZOOM_FACTOR, delta / 10.0);
 208
 209     if (options->zoom_pointer) {
 210         center_x = press1_win_x;
 211         center_y = press1_win_y;
 212     } else {
 213         center_x = rt->wid_size->width / 2.0;
 214         center_y = rt->wid_size->height / 2.0;
 215     }
 216
 217     matrix_zoom(ratio, center_x, center_y);
 218
 219     return REFRESH_BURST | REFRESH_STATUS;
 220 }
 221
 222 static gboolean motion_notify_event(GtkWidget * unused, GdkEventMotion * event)
 223 {
 224     /* move_pointer() generates a motion_notify_event, useless here. */
 225     static gboolean skip = FALSE;
 226     gint what = 0;
 227
 228     if (skip) {
 229         /* We come just after a move_pointer(). */
 230         skip = FALSE;
 231         return TRUE;
 232     }
 233
 234     if (rt->cursor_hidden)
 235         show_cursor();
 236     else
 237         schedule_hide_cursor();
 238
 239     if (event->state & GDK_BUTTON1_MASK) {
 240
 241         if (event->state & (GDK_CONTROL_MASK | GDK_SHIFT_MASK)) {
 242             if (event->state & GDK_CONTROL_MASK)
 243                 what = process_rotation(event);
 244
 245             if (event->state & GDK_SHIFT_MASK)
 246                 what |= process_zoom(event);
 247         } else
 248             what = process_move(event);
 249
 250         refresh(what);
 251
 252         update_coordinates1(event);
 253         skip = warp_pointer(event->x_root, event->y_root);
 254
 255     } else if (event->state & GDK_BUTTON3_MASK) {
 256
 257         /* We draw the zoom rectangle. */
 258         set_zoom_frame(old3_win_x, old3_win_y,
 259                        (gint) event->x - old3_win_x,
 260                        (gint) event->y - old3_win_y);
 261
 262         draw_zoom_frame();
 263     }
 264
 265     return TRUE;
 266 }
 267
 268 /* Called when pressing an arrow key. */
 269 static void move_or_rotate(guint state, gfloat x, gfloat y, gfloat angle)
 270 {
 271     guint what = REFRESH_IMAGE | APPEND_HISTORY;
 272
 273     if (state & GDK_CONTROL_MASK) {
 274         matrix_rotate(angle);
 275         what |= REFRESH_STATUS;
 276     } else
 277         matrix_move(x, y);
 278
 279     refresh(what);
 280 }
 281
 282 /* Mask to keep track of which arrow keys are pressed. */
 283 #define ARROW_UP    (1 << 0)
 284 #define ARROW_LEFT  (1 << 1)
 285 #define ARROW_RIGHT (1 << 2)
 286 #define ARROW_DOWN  (1 << 3)
 287
 288 /* Called twice to know how far we move in the two directions. */
 289 static gfloat get_arrow_move(guint state, guint flag_pos, guint flag_neg)
 290 {
 291     guint flags;
 292
 293     flags = state & (flag_pos | flag_neg);
 294
 295     if (flags == (flag_pos | flag_neg) || flags == 0)
 296         /* Both keys are pressed, or none => don't move. */
 297         return 0.0;
 298
 299     if (state & flag_pos)
 300         /* Left or up. */
 301         return MOVE_OFFSET;
 302
 303     /* Right or down. */
 304     return -MOVE_OFFSET;
 305 }
 306
 307 /* An arrow key or something else was either pressed or released. */
 308 static gboolean process_arrow_key(GdkEventKey * event, gboolean press)
 309 {
 310     static guint arrow_state = 0;
 311     guint arrow;
 312     gfloat x, y, angle;
 313
 314     switch (event->keyval) {
 315     case GDK_Up:
 316     case GDK_KP_Up:
 317         arrow = ARROW_UP;
 318         angle = BIG_ROTATION;
 319         break;
 320
 321     case GDK_Left:
 322     case GDK_KP_Left:
 323         arrow = ARROW_LEFT;
 324         angle = SMALL_ROTATION;
 325         break;
 326
 327     case GDK_Right:
 328     case GDK_KP_Right:
 329         arrow = ARROW_RIGHT;
 330         angle = -SMALL_ROTATION;
 331         break;
 332
 333     case GDK_Down:
 334     case GDK_KP_Down:
 335         arrow = ARROW_DOWN;
 336         angle = -BIG_ROTATION;
 337         break;
 338
 339     default:
 340         /* Key not found, try a keyboard accelerator. */
 341         return FALSE;
 342     }
 343
 344     if (press)
 345         arrow_state |= arrow;
 346     else
 347         arrow_state &= ~arrow;
 348
 349     if (press) {
 350         x = get_arrow_move(arrow_state, ARROW_LEFT, ARROW_RIGHT);
 351         y = get_arrow_move(arrow_state, ARROW_UP, ARROW_DOWN);
 352
 353         move_or_rotate(event->state, x, y, angle);
 354     }
 355
 356     return FALSE;
 357 }
 358
 359 static gboolean key_press_event(GtkWidget * unused, GdkEventKey * event)
 360 {
 361     /* Most keys are handled via keyboard accelerators. */
 362     switch (event->keyval) {
 363     case GDK_Escape:
 364         gui_quit();
 365         break;
 366
 367     case GDK_KP_Space:
 368     case GDK_space:
 369         load_direction(1);
 370         break;
 371
 372     case GDK_BackSpace:
 373         load_direction(-1);
 374         break;
 375
 376     case GDK_minus:
 377     case GDK_KP_Subtract:
 378         zoom_in(1.0 / ZOOM_FACTOR);
 379         break;
 380
 381     case GDK_plus:
 382     case GDK_KP_Add:
 383     case GDK_equal:
 384         zoom_in(ZOOM_FACTOR);
 385         break;
 386
 387     default:
 388         /* Key not found, try an arrow key, */
 389         if (process_arrow_key(event, TRUE) == FALSE)
 390             /* or an accelerator without the Ctrl modifier. */
 391             event->state &= ~GDK_CONTROL_MASK;
 392     }
 393
 394     return FALSE;
 395 }
 396
 397 static gboolean key_release_event(GtkWidget * unused, GdkEventKey * event)
 398 {
 399     return process_arrow_key(event, FALSE);
 400 }
 401
 402 static gboolean scroll_event(GtkWidget * unused, GdkEventScroll * event)
 403 {
 404     if (mouse_wheel_zoom) {
 405
 406         if (event->direction == GDK_SCROLL_UP)
 407             zoom_in(1.0 / ZOOM_FACTOR);
 408
 409         else if (event->direction == GDK_SCROLL_DOWN)
 410             zoom_in(ZOOM_FACTOR);
 411
 412     } else {
 413         /* mouse_wheel_zoom == FALSE */
 414
 415         if (event->direction == GDK_SCROLL_UP)
 416             load_direction(-1);
 417
 418         else if (event->direction == GDK_SCROLL_DOWN)
 419             load_direction(1);
 420     }
 421
 422     return TRUE;
 423 }
 424
 425 void install_callbacks(gpointer object)
 426 {
 427     g_signal_connect(object, "button-press-event",
 428                      G_CALLBACK(button_press_event), NULL);
 429
 430     g_signal_connect(object, "button-release-event",
 431                      G_CALLBACK(button_release_event), NULL);
 432
 433     g_signal_connect(object, "motion-notify-event",
 434                      G_CALLBACK(motion_notify_event), NULL);
 435
 436     g_signal_connect(object, "key-press-event",
 437                      G_CALLBACK(key_press_event), NULL);
 438
 439     g_signal_connect(object, "key-release-event",
 440                      G_CALLBACK(key_release_event), NULL);
 441
 442     g_signal_connect(object, "delete-event", G_CALLBACK(gui_quit), NULL);
 443
 444     g_signal_connect(object, "scroll-event", G_CALLBACK(scroll_event), NULL);
 445
 446     g_signal_connect_after(object, "button-press-event",
 447                            G_CALLBACK(set_correct_cursor), NULL);
 448
 449     g_signal_connect_after(object, "button-release-event",
 450                            G_CALLBACK(set_correct_cursor), NULL);
 451
 452     g_signal_connect_after(object, "key-press-event",
 453                            G_CALLBACK(set_correct_cursor), NULL);
 454
 455     g_signal_connect_after(object, "key-release-event",
 456                            G_CALLBACK(set_correct_cursor), NULL);
 457
 458     g_signal_connect_after(object, "focus-in-event",
 459                            G_CALLBACK(set_correct_cursor), NULL);
 460 }
 461
 462 /*
 463  * We call process_events() when rebuilding the images menus and to wait for a
 464  * refresh.
 465  */
 466 void process_events(void)
 467 {
 468     while (gtk_events_pending() != 0)
 469         gtk_main_iteration_do(FALSE);
 470 }