Pileus Git - grits/blob - src/grits-viewer.c

   1 /*
   2  * Copyright (C) 2009-2011 Andy Spencer <andy753421@gmail.com>
   3  *
   4  * This program is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 3 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program 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
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 /**
  19  * SECTION:grits-viewer
  20  * @short_description: Virtual globe base class
  21  *
  22  * #GritsViewer is the base class for the virtual globe widget. It handles
  23  * everything not directly related to drawing the globe. Plugins and
  24  * applications using the viewer should normally talk to the viewer and not care
  25  * how it is implemented.
  26  */
  27
  28 #include <config.h>
  29 #include <math.h>
  30 #include <gtk/gtk.h>
  31 #include <gdk/gdkkeysyms.h>
  32
  33 #include "grits-marshal.h"
  34 #include "grits-viewer.h"
  35
  36 #include "grits-util.h"
  37
  38
  39 /* Constants */
  40 enum {
  41         SIG_TIME_CHANGED,
  42         SIG_LOCATION_CHANGED,
  43         SIG_ROTATION_CHANGED,
  44         SIG_REFRESH,
  45         SIG_OFFLINE,
  46         NUM_SIGNALS,
  47 };
  48 static guint signals[NUM_SIGNALS];
  49
  50
  51 /***********
  52  * Helpers *
  53  ***********/
  54 /* Misc helpers */
  55 static void _grits_viewer_fix_location(GritsViewer *viewer)
  56 {
  57         while (viewer->location[0] <  -90) viewer->location[0] += 180;
  58         while (viewer->location[0] >   90) viewer->location[0] -= 180;
  59         while (viewer->location[1] < -180) viewer->location[1] += 360;
  60         while (viewer->location[1] >  180) viewer->location[1] -= 360;
  61         viewer->location[2] = ABS(viewer->location[2]);
  62 }
  63
  64 /* Signal helpers */
  65 static void _grits_viewer_emit_location_changed(GritsViewer *viewer)
  66 {
  67         g_signal_emit(viewer, signals[SIG_LOCATION_CHANGED], 0,
  68                         viewer->location[0],
  69                         viewer->location[1],
  70                         viewer->location[2]);
  71 }
  72 static void _grits_viewer_emit_rotation_changed(GritsViewer *viewer)
  73 {
  74         g_signal_emit(viewer, signals[SIG_ROTATION_CHANGED], 0,
  75                         viewer->rotation[0],
  76                         viewer->rotation[1],
  77                         viewer->rotation[2]);
  78 }
  79 static void _grits_viewer_emit_time_changed(GritsViewer *viewer)
  80 {
  81         g_signal_emit(viewer, signals[SIG_TIME_CHANGED], 0,
  82                         viewer->time);
  83 }
  84 static void _grits_viewer_emit_refresh(GritsViewer *viewer)
  85 {
  86         g_signal_emit(viewer, signals[SIG_REFRESH], 0);
  87 }
  88 static void _grits_viewer_emit_offline(GritsViewer *viewer)
  89 {
  90         g_signal_emit(viewer, signals[SIG_OFFLINE], 0,
  91                         viewer->offline);
  92 }
  93
  94 /*************
  95  * Callbacks *
  96  *************/
  97 static gboolean on_key_press(GritsViewer *viewer, GdkEventKey *event, gpointer _)
  98 {
  99         g_debug("GritsViewer: on_key_press - key=%x, state=%x, plus=%x",
 100                         event->keyval, event->state, GDK_plus);
 101
 102         double lat, lon, elev, pan;
 103         grits_viewer_get_location(viewer, &lat, &lon, &elev);
 104         pan = MIN(elev/(EARTH_R/2), 30);
 105         switch (event->keyval) {
 106         case GDK_Left:  case GDK_h: grits_viewer_pan(viewer,  0,  -pan, 0); break;
 107         case GDK_Down:  case GDK_j: grits_viewer_pan(viewer, -pan, 0,   0); break;
 108         case GDK_Up:    case GDK_k: grits_viewer_pan(viewer,  pan, 0,   0); break;
 109         case GDK_Right: case GDK_l: grits_viewer_pan(viewer,  0,   pan, 0); break;
 110         case GDK_minus: case GDK_o: grits_viewer_zoom(viewer, 10./9); break;
 111         case GDK_plus:  case GDK_i: grits_viewer_zoom(viewer, 9./10); break;
 112         case GDK_H: grits_viewer_rotate(viewer,  0, 0, -2); break;
 113         case GDK_J: grits_viewer_rotate(viewer,  2, 0,  0); break;
 114         case GDK_K: grits_viewer_rotate(viewer, -2, 0,  0); break;
 115         case GDK_L: grits_viewer_rotate(viewer,  0, 0,  2); break;
 116         }
 117         return FALSE;
 118 }
 119
 120 static gboolean on_scroll(GritsViewer *viewer, GdkEventScroll *event, gpointer _)
 121 {
 122         switch (event->direction) {
 123         case GDK_SCROLL_DOWN: grits_viewer_zoom(viewer, 10./9); break;
 124         case GDK_SCROLL_UP:   grits_viewer_zoom(viewer, 9./10); break;
 125         default: break;
 126         }
 127         return FALSE;
 128 }
 129
 130 enum {
 131         GRITS_DRAG_NONE,
 132         GRITS_DRAG_PAN,
 133         GRITS_DRAG_ZOOM,
 134         GRITS_DRAG_TILT,
 135 };
 136
 137 static gboolean on_button_press(GritsViewer *viewer, GdkEventButton *event, gpointer _)
 138 {
 139         g_debug("GritsViewer: on_button_press - %d", event->button);
 140         gtk_widget_grab_focus(GTK_WIDGET(viewer));
 141         switch (event->button) {
 142         case 1:  viewer->drag_mode = GRITS_DRAG_PAN;  break;
 143         case 2:  viewer->drag_mode = GRITS_DRAG_ZOOM; break;
 144         case 3:  viewer->drag_mode = GRITS_DRAG_TILT; break;
 145         default: viewer->drag_mode = GRITS_DRAG_NONE; break;
 146         }
 147         viewer->drag_x = event->x;
 148         viewer->drag_y = event->y;
 149         return FALSE;
 150 }
 151
 152 static gboolean on_button_release(GritsViewer *viewer, GdkEventButton *event, gpointer _)
 153 {
 154         g_debug("GritsViewer: on_button_release");
 155         viewer->drag_mode = GRITS_DRAG_NONE;
 156         return FALSE;
 157 }
 158
 159 static gboolean on_motion_notify(GritsViewer *viewer, GdkEventMotion *event, gpointer _)
 160 {
 161         gdouble x = viewer->drag_x - event->x;
 162         gdouble y = viewer->drag_y - event->y;
 163         gdouble lat, lon, elev, scale, rx, ry, rz;
 164         grits_viewer_get_location(GRITS_VIEWER(viewer), &lat, &lon, &elev);
 165         grits_viewer_get_rotation(GRITS_VIEWER(viewer), &rx,  &ry,  &rz);
 166         scale = (elev/EARTH_R/14.1) * (sin(deg2rad(ABS(rx)))*4+1);
 167         switch (viewer->drag_mode) {
 168         case GRITS_DRAG_PAN:  grits_viewer_pan(viewer, -y*scale*0.782, x*scale, 0); break;
 169         case GRITS_DRAG_ZOOM: grits_viewer_zoom(viewer, pow(2, -y/500)); break;
 170         case GRITS_DRAG_TILT: grits_viewer_rotate(viewer, y/10, 0, x/10); break;
 171         }
 172         viewer->drag_x = event->x;
 173         viewer->drag_y = event->y;
 174         return FALSE;
 175 }
 176
 177 static void on_view_changed(GritsViewer *viewer,
 178                 gdouble _1, gdouble _2, gdouble _3)
 179 {
 180         gtk_widget_queue_draw(GTK_WIDGET(viewer));
 181 }
 182
 183 static void on_realize(GritsViewer *viewer)
 184 {
 185         GdkCursor *cursor = gdk_cursor_new(GDK_FLEUR);
 186         GdkWindow *window = gtk_widget_get_window(GTK_WIDGET(viewer));
 187         gdk_window_set_cursor(window, cursor);
 188 }
 189
 190 /***********
 191  * Methods *
 192  ***********/
 193 /**
 194  * grits_viewer_setup:
 195  * @viewer:  the viewer
 196  * @plugins: a plugins store
 197  * @prefs:   a prefs store
 198  *
 199  * This should be called by objects which implement GritsViewer somewhere in their
 200  * constructor.
 201  */
 202 void grits_viewer_setup(GritsViewer *viewer, GritsPlugins *plugins, GritsPrefs *prefs)
 203 {
 204         viewer->plugins = plugins;
 205         viewer->prefs   = prefs;
 206         viewer->offline = grits_prefs_get_boolean(prefs, "grits/offline", NULL);
 207 }
 208
 209 /**
 210  * grits_viewer_set_time:
 211  * @viewer: the viewer
 212  * @time: the time to set the view to
 213  *
 214  * Set the current time for the view
 215  */
 216 void grits_viewer_set_time(GritsViewer *viewer, time_t time)
 217 {
 218         g_assert(GRITS_IS_VIEWER(viewer));
 219         g_debug("GritsViewer: set_time - time=%ld", time);
 220         viewer->time = time;
 221         _grits_viewer_emit_time_changed(viewer);
 222 }
 223
 224 /**
 225  * grits_viewer_get_time:
 226  * @viewer: the viewer
 227  *
 228  * Get the time that is being viewed
 229  *
 230  * Returns: the current time
 231  */
 232 time_t grits_viewer_get_time(GritsViewer *viewer)
 233 {
 234         g_assert(GRITS_IS_VIEWER(viewer));
 235         g_debug("GritsViewer: get_time");
 236         return viewer->time;
 237 }
 238
 239 /**
 240  * grits_viewer_set_location:
 241  * @viewer: the viewer
 242  * @lat:  the new latitude
 243  * @lon:  the new longitude
 244  * @elev: the new elevation
 245  *
 246  * Set the location for the camera
 247  */
 248 void grits_viewer_set_location(GritsViewer *viewer, gdouble lat, gdouble lon, gdouble elev)
 249 {
 250         g_assert(GRITS_IS_VIEWER(viewer));
 251         g_debug("GritsViewer: set_location");
 252         viewer->location[0] = lat;
 253         viewer->location[1] = lon;
 254         viewer->location[2] = elev;
 255         _grits_viewer_fix_location(viewer);
 256         _grits_viewer_emit_location_changed(viewer);
 257 }
 258
 259 /**
 260  * grits_viewer_get_location:
 261  * @viewer: the viewer
 262  * @lat:  the location to store the latitude
 263  * @lon:  the location to store the longitude
 264  * @elev: the location to store the elevation
 265  *
 266  * Get the location of the camera
 267  */
 268 void grits_viewer_get_location(GritsViewer *viewer, gdouble *lat, gdouble *lon, gdouble *elev)
 269 {
 270         g_assert(GRITS_IS_VIEWER(viewer));
 271         //g_debug("GritsViewer: get_location");
 272         *lat  = viewer->location[0];
 273         *lon  = viewer->location[1];
 274         *elev = viewer->location[2];
 275 }
 276
 277 /**
 278  * grits_viewer_pan:
 279  * @viewer: the viewer
 280  * @forward:  distance to move forward in meters
 281  * @right:    distance to move right in meters
 282  * @up:       distance to move up in meters
 283  *
 284  * Pan the location by a number of meters long the surface.
 285  *
 286  * Bugs: the distances are not in meters
 287  * Bugs: panning does not move in strait lines
 288  */
 289 void grits_viewer_pan(GritsViewer *viewer, gdouble forward, gdouble sideways, gdouble up)
 290 {
 291         g_assert(GRITS_IS_VIEWER(viewer));
 292         g_debug("GritsViewer: pan - forward=%8.3f, sideways=%8.3f, up=%8.3f",
 293                         forward, sideways, up);
 294         gdouble dist   = sqrt(forward*forward + sideways*sideways);
 295         gdouble angle1 = deg2rad(viewer->rotation[2]);
 296         gdouble angle2 = atan2(sideways, forward);
 297         gdouble angle  = angle1 + angle2;
 298         /* This isn't accurate, but it's usable */
 299         viewer->location[0] += dist*cos(angle);
 300         viewer->location[1] += dist*sin(angle);
 301         viewer->location[2] += up;
 302         _grits_viewer_fix_location(viewer);
 303         _grits_viewer_emit_location_changed(viewer);
 304 }
 305
 306 /**
 307  * grits_viewer_zoom:
 308  * @viewer: the viewer
 309  * @scale: the scale to multiple the elevation by
 310  *
 311  * Multiple the elevation by a scale.
 312  */
 313 void grits_viewer_zoom(GritsViewer *viewer, gdouble scale)
 314 {
 315         g_assert(GRITS_IS_VIEWER(viewer));
 316         g_debug("GritsViewer: zoom");
 317         viewer->location[2] *= scale;
 318         _grits_viewer_emit_location_changed(viewer);
 319 }
 320
 321 /**
 322  * grits_viewer_set_rotation:
 323  * @viewer: the viewer
 324  * @x: rotation new around the x axes
 325  * @y: rotation new around the y axes
 326  * @z: rotation new around the z axes
 327  *
 328  * Set the rotations in degrees around the x, y, and z axes.
 329  */
 330 void grits_viewer_set_rotation(GritsViewer *viewer, gdouble x, gdouble y, gdouble z)
 331 {
 332         g_assert(GRITS_IS_VIEWER(viewer));
 333         g_debug("GritsViewer: set_rotation");
 334         viewer->rotation[0] = x;
 335         viewer->rotation[1] = y;
 336         viewer->rotation[2] = z;
 337         _grits_viewer_emit_rotation_changed(viewer);
 338 }
 339
 340 /**
 341  * grits_viewer_get_rotation:
 342  * @viewer: the viewer
 343  * @x: rotation around the x axes
 344  * @y: rotation around the y axes
 345  * @z: rotation around the z axes
 346  *
 347  * Get the rotations in degrees around the x, y, and z axes.
 348  */
 349 void grits_viewer_get_rotation(GritsViewer *viewer, gdouble *x, gdouble *y, gdouble *z)
 350 {
 351         g_assert(GRITS_IS_VIEWER(viewer));
 352         //g_debug("GritsViewer: get_rotation");
 353         *x = viewer->rotation[0];
 354         *y = viewer->rotation[1];
 355         *z = viewer->rotation[2];
 356 }
 357
 358 /**
 359  * grits_viewer_rotate:
 360  * @viewer: the viewer
 361  * @x: rotation around the x axes
 362  * @y: rotation around the y axes
 363  * @z: rotation around the z axes
 364  *
 365  * Add to the rotation around the x, y, and z axes.
 366  */
 367 void grits_viewer_rotate(GritsViewer *viewer, gdouble x, gdouble y, gdouble z)
 368 {
 369         g_assert(GRITS_IS_VIEWER(viewer));
 370         g_debug("GritsViewer: rotate - x=%.0f, y=%.0f, z=%.0f", x, y, z);
 371         viewer->rotation[0] += x;
 372         viewer->rotation[1] += y;
 373         viewer->rotation[2] += z;
 374         _grits_viewer_emit_rotation_changed(viewer);
 375 }
 376
 377 /**
 378  * grits_viewer_refresh:
 379  * @viewer: the viewer
 380  *
 381  * Trigger the refresh signal. This will cause any remote data to be checked for
 382  * updates.
 383  */
 384 void grits_viewer_refresh(GritsViewer *viewer)
 385 {
 386         g_debug("GritsViewer: refresh");
 387         _grits_viewer_emit_refresh(viewer);
 388 }
 389
 390 /**
 391  * grits_viewer_set_offline:
 392  * @viewer: the viewer
 393  * @offline: %TRUE to enter offline mode
 394  *
 395  * Set the offline mode. If @offline is %TRUE, only locally cached data will be
 396  * used.
 397  */
 398 void grits_viewer_set_offline(GritsViewer *viewer, gboolean offline)
 399 {
 400         g_assert(GRITS_IS_VIEWER(viewer));
 401         g_debug("GritsViewer: set_offline - %d", offline);
 402         grits_prefs_set_boolean(viewer->prefs, "grits/offline", offline);
 403         viewer->offline = offline;
 404         _grits_viewer_emit_offline(viewer);
 405 }
 406
 407 /**
 408  * grits_viewer_get_offline:
 409  * @viewer: the viewer
 410  *
 411  * Check if the viewer is in offline mode.
 412  *
 413  * Returns: %TRUE if the viewer is in offline mode.
 414  */
 415 gboolean grits_viewer_get_offline(GritsViewer *viewer)
 416 {
 417         g_assert(GRITS_IS_VIEWER(viewer));
 418         g_debug("GritsViewer: get_offline - %d", viewer->offline);
 419         return viewer->offline;
 420 }
 421
 422 /***********************************
 423  * To be implemented by subclasses *
 424  ***********************************/
 425 /**
 426  * grits_viewer_center_position:
 427  * @viewer: the viewer
 428  * @lat:  the latitude
 429  * @lon:  the longitude
 430  * @elev: the elevation
 431  *
 432  * Center the viewer on a point. This can be used before drawing operations to
 433  * center the items a particular location.
 434  */
 435 void grits_viewer_center_position(GritsViewer *viewer,
 436                 gdouble lat, gdouble lon, gdouble elev)
 437 {
 438         GritsViewerClass *klass = GRITS_VIEWER_GET_CLASS(viewer);
 439         if (!klass->center_position)
 440                 g_warning("GritsViewer: center_position - Unimplemented");
 441         klass->center_position(viewer, lat, lon, elev);
 442 }
 443
 444 /**
 445  * grits_viewer_project:
 446  * @viewer: the viewer
 447  * @lat:  the latitude
 448  * @lon:  the longitude
 449  * @elev: the elevation
 450  * @px:   the project x coordinate
 451  * @py:   the project y coordinate
 452  * @pz:   the project z coordinate
 453  *
 454  * Project a latitude, longitude, elevation point to to x, y, and z coordinates
 455  * in screen space. Useful for drawing orthographic data over a particular point
 456  * in space. E.g. #GritsMarker.
 457  */
 458 void grits_viewer_project(GritsViewer *viewer,
 459                 gdouble lat, gdouble lon, gdouble elev,
 460                 gdouble *px, gdouble *py, gdouble *pz)
 461 {
 462         GritsViewerClass *klass = GRITS_VIEWER_GET_CLASS(viewer);
 463         if (!klass->project)
 464                 g_warning("GritsViewer: project - Unimplemented");
 465         klass->project(viewer, lat, lon, elev, px, py, pz);
 466 }
 467
 468 /**
 469  * grits_viewer_unproject:
 470  * @viewer: the viewer
 471  * @x:    x coordinate in screen space
 472  * @y:    y coordinate in screen space
 473  * @z:    z coordinate in screen space, or -1 to use the value
 474  *        from the depth buffer at x and y as the z value
 475  * @lat:  the latitude
 476  * @lon:  the longitude
 477  * @elev: the elevation
 478  *
 479  * Project a x, y point in screen space to a latitude, longitude, and elevation
 480  * point. Useful for finding the position of the cursor or another on-screen
 481  * object in world coordinates.
 482  */
 483 void grits_viewer_unproject(GritsViewer *viewer,
 484                 gdouble px, gdouble py, gdouble pz,
 485                 gdouble *lat, gdouble *lon, gdouble *elev)
 486 {
 487         GritsViewerClass *klass = GRITS_VIEWER_GET_CLASS(viewer);
 488         if (!klass->unproject)
 489                 g_warning("GritsViewer: unproject - Unimplemented");
 490         klass->unproject(viewer, px, py, pz, lat, lon, elev);
 491 }
 492
 493 /**
 494  * grits_viewer_clear_height_func:
 495  * @viewer: the viewer
 496  *
 497  * Clears the height function for the entire viewer. Useful when an elevation
 498  * plugin is unloaded.
 499  */
 500 void grits_viewer_clear_height_func(GritsViewer *viewer)
 501 {
 502         GritsViewerClass *klass = GRITS_VIEWER_GET_CLASS(viewer);
 503         if (!klass->clear_height_func)
 504                 g_warning("GritsViewer: clear_height_func - Unimplemented");
 505         klass->clear_height_func(viewer);
 506 }
 507
 508 /**
 509  * grits_viewer_set_height_func:
 510  * @viewer:      the viewer
 511  * @bounds:      the area to set the height function for
 512  * @height_func: the height function
 513  * @user_data:   user data to pass to the height function
 514  * @update:      %TRUE if the heights inside the bounds should be updated.
 515  *
 516  * Set the height function to be used for a given part of the surface..
 517  */
 518 void grits_viewer_set_height_func(GritsViewer *viewer, GritsBounds *bounds,
 519                 GritsHeightFunc height_func, gpointer user_data,
 520                 gboolean update)
 521 {
 522         GritsViewerClass *klass = GRITS_VIEWER_GET_CLASS(viewer);
 523         if (!klass->set_height_func)
 524                 g_warning("GritsViewer: set_height_func - Unimplemented");
 525         klass->set_height_func(viewer, bounds, height_func, user_data, update);
 526 }
 527
 528 /**
 529  * grits_viewer_add:
 530  * @viewer: the viewer
 531  * @object: the object to add
 532  * @level:  the level to add the object to
 533  * @sort:   %TRUE if the object should be depth-sorted prior to being drawn
 534  *
 535  * Objects which are added to the viewer will be drawn on subsequent renderings
 536  * if their level of details is adequate.
 537  *
 538  * The @level represents the order the object should be drawn in, this is
 539  * unrelated to the objects actual position in the world.
 540  *
 541  * Semi-transparent objects should set @sort to %TRUE so that they are rendered
 542  * correctly when they overlap other semi-transparent objects.
 543  *
 544  * The viewer steals the objects reference. Call g_object_ref if you plan on
 545  * holding a reference as well.
 546  *
 547  * Returns: a handle to be pass to grits_viewer_remove()
 548  */
 549 gpointer grits_viewer_add(GritsViewer *viewer, GritsObject *object,
 550                 gint level, gboolean sort)
 551 {
 552         GritsViewerClass *klass = GRITS_VIEWER_GET_CLASS(viewer);
 553         if (!klass->add)
 554                 g_warning("GritsViewer: add - Unimplemented");
 555         object->ref    = klass->add(viewer, object, level, sort);
 556         object->viewer = viewer;
 557         return object;
 558 }
 559
 560 /**
 561  * grits_viewer_remove:
 562  * @viewer: the viewer
 563  * @ref:    the handle obtained from grits_viewer_add()
 564  *
 565  * Remove an object from the viewer. The objects reference count is decremented
 566  * prior to being removed.
 567  *
 568  * Returns: the #GritsObject referenced by the handle
 569  */
 570 GritsObject *grits_viewer_remove(GritsViewer *viewer, GritsObject *object)
 571 {
 572         GritsViewerClass *klass = GRITS_VIEWER_GET_CLASS(viewer);
 573         if (!klass->remove)
 574                 g_warning("GritsViewer: remove - Unimplemented");
 575         klass->remove(viewer, object);
 576         return object;
 577 }
 578
 579 /****************
 580  * GObject code *
 581  ****************/
 582 G_DEFINE_ABSTRACT_TYPE(GritsViewer, grits_viewer, GTK_TYPE_DRAWING_AREA);
 583 static void grits_viewer_init(GritsViewer *viewer)
 584 {
 585         g_debug("GritsViewer: init");
 586         /* Default values */
 587         viewer->time        = time(NULL);
 588         viewer->location[0] = 40;
 589         viewer->location[1] = -100;
 590         viewer->location[2] = EARTH_R;
 591         viewer->rotation[0] = 0;
 592         viewer->rotation[1] = 0;
 593         viewer->rotation[2] = 0;
 594
 595         g_object_set(viewer, "can-focus", TRUE, NULL);
 596         gtk_widget_add_events(GTK_WIDGET(viewer),
 597                         GDK_BUTTON_PRESS_MASK |
 598                         GDK_BUTTON_RELEASE_MASK |
 599                         GDK_POINTER_MOTION_MASK |
 600                         GDK_KEY_PRESS_MASK);
 601
 602         g_signal_connect(viewer, "key-press-event",      G_CALLBACK(on_key_press),      NULL);
 603         g_signal_connect(viewer, "scroll-event",         G_CALLBACK(on_scroll),         NULL);
 604
 605         g_signal_connect(viewer, "button-press-event",   G_CALLBACK(on_button_press),   NULL);
 606         g_signal_connect(viewer, "button-release-event", G_CALLBACK(on_button_release), NULL);
 607         g_signal_connect(viewer, "motion-notify-event",  G_CALLBACK(on_motion_notify),  NULL);
 608
 609         g_signal_connect(viewer, "location-changed",     G_CALLBACK(on_view_changed),   NULL);
 610         g_signal_connect(viewer, "rotation-changed",     G_CALLBACK(on_view_changed),   NULL);
 611
 612         g_signal_connect(viewer, "realize",              G_CALLBACK(on_realize),        NULL);
 613 }
 614 static void grits_viewer_finalize(GObject *gobject)
 615 {
 616         g_debug("GritsViewer: finalize");
 617         G_OBJECT_CLASS(grits_viewer_parent_class)->finalize(gobject);
 618         g_debug("GritsViewer: finalize - done");
 619 }
 620 static void grits_viewer_class_init(GritsViewerClass *klass)
 621 {
 622         g_debug("GritsViewer: class_init");
 623         GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
 624         gobject_class->finalize     = grits_viewer_finalize;
 625
 626         /**
 627          * GritsViewer::time-changed:
 628          * @viewer: the viewer.
 629          * @time:   the new time.
 630          *
 631          * The ::time-changed signal is emitted when the viewers current time
 632          * changers.
 633          */
 634         signals[SIG_TIME_CHANGED] = g_signal_new(
 635                         "time-changed",
 636                         G_TYPE_FROM_CLASS(gobject_class),
 637                         G_SIGNAL_RUN_LAST,
 638                         0,
 639                         NULL,
 640                         NULL,
 641                         g_cclosure_marshal_VOID__LONG,
 642                         G_TYPE_NONE,
 643                         1,
 644                         G_TYPE_LONG);
 645
 646         /**
 647          * GritsViewer::location-changed:
 648          * @viewer: the viewer.
 649          * @lat:    the new latitude.
 650          * @lon:    the new longitude.
 651          * @elev:   the new elevation.
 652          *
 653          * The ::location-changed signal is emitted when the viewers camera
 654          * location changes.
 655          */
 656         signals[SIG_LOCATION_CHANGED] = g_signal_new(
 657                         "location-changed",
 658                         G_TYPE_FROM_CLASS(gobject_class),
 659                         G_SIGNAL_RUN_LAST,
 660                         0,
 661                         NULL,
 662                         NULL,
 663                         grits_cclosure_marshal_VOID__DOUBLE_DOUBLE_DOUBLE,
 664                         G_TYPE_NONE,
 665                         3,
 666                         G_TYPE_DOUBLE,
 667                         G_TYPE_DOUBLE,
 668                         G_TYPE_DOUBLE);
 669
 670         /**
 671          * GritsViewer::rotation-changed:
 672          * @viewer: the viewer.
 673          * @x: rotation new around the x axes.
 674          * @y: rotation new around the y axes.
 675          * @z: rotation new around the z axes.
 676          *
 677          * The ::rotation-changed signal is emitted when the viewers cameras
 678          * rotation changes.
 679          */
 680         signals[SIG_ROTATION_CHANGED] = g_signal_new(
 681                         "rotation-changed",
 682                         G_TYPE_FROM_CLASS(gobject_class),
 683                         G_SIGNAL_RUN_LAST,
 684                         0,
 685                         NULL,
 686                         NULL,
 687                         grits_cclosure_marshal_VOID__DOUBLE_DOUBLE_DOUBLE,
 688                         G_TYPE_NONE,
 689                         3,
 690                         G_TYPE_DOUBLE,
 691                         G_TYPE_DOUBLE,
 692                         G_TYPE_DOUBLE);
 693
 694         /**
 695          * GritsViewer::refresh:
 696          * @viewer: the viewer.
 697          *
 698          * The ::refresh signal is emitted when a refresh is needed. If you are
 699          * using real-time data from a remote server, you should connect to the
 700          * refresh signal and update the data when necessary.
 701          */
 702         signals[SIG_REFRESH] = g_signal_new(
 703                         "refresh",
 704                         G_TYPE_FROM_CLASS(gobject_class),
 705                         G_SIGNAL_RUN_LAST,
 706                         0,
 707                         NULL,
 708                         NULL,
 709                         g_cclosure_marshal_VOID__VOID,
 710                         G_TYPE_NONE,
 711                         0);
 712
 713         /**
 714          * GritsViewer::offline:
 715          * @viewer:  the viewer.
 716          * @offline: %TRUE if the viewer going offline.
 717          *
 718          * The ::offline signal is emitted when the viewers offline mode
 719          * changes.
 720          */
 721         signals[SIG_OFFLINE] = g_signal_new(
 722                         "offline",
 723                         G_TYPE_FROM_CLASS(gobject_class),
 724                         G_SIGNAL_RUN_LAST,
 725                         0,
 726                         NULL,
 727                         NULL,
 728                         g_cclosure_marshal_VOID__BOOLEAN,
 729                         G_TYPE_NONE,
 730                         1,
 731                         G_TYPE_BOOLEAN);
 732 }