Pileus Git - grits/blob - src/grits-opengl.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-opengl
  20  * @short_description: OpenGL based virtual globe
  21  *
  22  * #GritsOpenGL is the core rendering engine used by grits. Theoretically other
  23  * renderers could be writte, but they have not been. GritsOpenGL uses the ROAM
  24  * algorithm for updating surface mesh the planet. The only thing GritsOpenGL
  25  * can actually render on it's own is a wireframe of a sphere.
  26  *
  27  * GritsOpenGL requires (at least) OpenGL 2.0.
  28  */
  29
  30 #include <config.h>
  31 #include <math.h>
  32 #include <string.h>
  33 #include <gdk/gdkkeysyms.h>
  34 #include <gtk/gtk.h>
  35
  36 #include "grits-opengl.h"
  37 #include "grits-util.h"
  38 #include "gtkgl.h"
  39 #include "roam.h"
  40
  41 // #define ROAM_DEBUG
  42
  43 /* Tessellation, "finding intersecting triangles" */
  44 /* http://research.microsoft.com/pubs/70307/tr-2006-81.pdf */
  45 /* http://www.opengl.org/wiki/Alpha_Blending */
  46
  47 /* The unsorted/sroted GLists are blank head nodes,
  48  * This way us we can remove objects from the level just by fixing up links
  49  * I.e. we don't need to do a lookup to remove an object if we have its GList */
  50 struct RenderLevel {
  51         GList unsorted;
  52         GList sorted;
  53 };
  54
  55 /***********
  56  * Helpers *
  57  ***********/
  58 static void _set_visuals(GritsOpenGL *opengl)
  59 {
  60         glMatrixMode(GL_MODELVIEW);
  61         glLoadIdentity();
  62
  63         /* Camera 1 */
  64         double lat, lon, elev, rx, ry, rz;
  65         grits_viewer_get_location(GRITS_VIEWER(opengl), &lat, &lon, &elev);
  66         grits_viewer_get_rotation(GRITS_VIEWER(opengl), &rx, &ry, &rz);
  67         glRotatef(rx, 1, 0, 0);
  68         glRotatef(rz, 0, 0, 1);
  69
  70         /* Lighting */
  71 #ifdef ROAM_DEBUG
  72         float light_ambient[]  = {0.7f, 0.7f, 0.7f, 1.0f};
  73         float light_diffuse[]  = {2.0f, 2.0f, 2.0f, 1.0f};
  74 #else
  75         float light_ambient[]  = {0.2f, 0.2f, 0.2f, 1.0f};
  76         float light_diffuse[]  = {0.8f, 0.8f, 0.8f, 1.0f};
  77 #endif
  78         float light_position[] = {-13*EARTH_R, 1*EARTH_R, 3*EARTH_R, 1.0f};
  79         glLightfv(GL_LIGHT0, GL_AMBIENT,  light_ambient);
  80         glLightfv(GL_LIGHT0, GL_DIFFUSE,  light_diffuse);
  81         glLightfv(GL_LIGHT0, GL_POSITION, light_position);
  82         glEnable(GL_LIGHT0);
  83         glEnable(GL_LIGHTING);
  84
  85         float material_ambient[]  = {1.0, 1.0, 1.0, 1.0};
  86         float material_diffuse[]  = {1.0, 1.0, 1.0, 1.0};
  87         float material_specular[] = {0.0, 0.0, 0.0, 1.0};
  88         float material_emission[] = {0.0, 0.0, 0.0, 1.0};
  89         glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT,  material_ambient);
  90         glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE,  material_diffuse);
  91         glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, material_specular);
  92         glMaterialfv(GL_FRONT_AND_BACK, GL_EMISSION, material_emission);
  93         glDisable(GL_TEXTURE_2D);
  94         glDisable(GL_COLOR_MATERIAL);
  95
  96         /* Camera 2 */
  97         glTranslatef(0, 0, -elev2rad(elev));
  98         glRotatef(lat, 1, 0, 0);
  99         glRotatef(-lon, 0, 1, 0);
 100
 101         glDisable(GL_ALPHA_TEST);
 102
 103         glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 104         glEnable(GL_BLEND);
 105
 106 #ifndef ROAM_DEBUG
 107         glCullFace(GL_BACK);
 108         glEnable(GL_CULL_FACE);
 109
 110         glClearDepth(1.0);
 111         glDepthFunc(GL_LEQUAL);
 112         glEnable(GL_DEPTH_TEST);
 113 #endif
 114
 115         glEnable(GL_LINE_SMOOTH);
 116
 117         glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
 118         //glShadeModel(GL_FLAT);
 119
 120         g_mutex_lock(opengl->sphere_lock);
 121         roam_sphere_update_view(opengl->sphere);
 122         g_mutex_unlock(opengl->sphere_lock);
 123 }
 124
 125 static gboolean _foreach_object_cb(gpointer key, gpointer value, gpointer pointers)
 126 {
 127         struct RenderLevel *level = value;
 128         GFunc    user_func = ((gpointer*)pointers)[0];
 129         gpointer user_data = ((gpointer*)pointers)[1];
 130         for (GList *cur = level->unsorted.next; cur; cur = cur->next)
 131                 user_func(cur->data, user_data);
 132         for (GList *cur = level->sorted.next;   cur; cur = cur->next)
 133                 user_func(cur->data, user_data);
 134         return FALSE;
 135 }
 136
 137 static void _foreach_object(GritsOpenGL *opengl, GFunc func, gpointer user_data)
 138 {
 139         gpointer pointers[2] = {func, user_data};
 140         g_tree_foreach(opengl->objects, _foreach_object_cb, pointers);
 141 }
 142
 143 static void _add_object(GritsObject *object, GPtrArray *array)
 144 {
 145         g_ptr_array_add(array, object);
 146 }
 147
 148 static GPtrArray *_objects_to_array(GritsOpenGL *opengl)
 149 {
 150         GPtrArray *array = g_ptr_array_new();
 151         _foreach_object(opengl, (GFunc)_add_object, array);
 152         return array;
 153 }
 154
 155 /*************
 156  * Callbacks *
 157  *************/
 158 static gboolean on_configure(GritsOpenGL *opengl, GdkEventConfigure *event, gpointer _)
 159 {
 160         g_debug("GritsOpenGL: on_configure");
 161
 162         double width  = GTK_WIDGET(opengl)->allocation.width;
 163         double height = GTK_WIDGET(opengl)->allocation.height;
 164
 165         /* Setup OpenGL Window */
 166         glViewport(0, 0, width, height);
 167         glMatrixMode(GL_PROJECTION);
 168         glLoadIdentity();
 169         double ang = atan(height/FOV_DIST);
 170         gluPerspective(rad2deg(ang)*2, width/height, 10, 100*EARTH_R);
 171
 172 #ifndef ROAM_DEBUG
 173         g_mutex_lock(opengl->sphere_lock);
 174         roam_sphere_update_errors(opengl->sphere);
 175         g_mutex_unlock(opengl->sphere_lock);
 176 #endif
 177
 178         return FALSE;
 179 }
 180
 181 static gboolean _draw_level(gpointer key, gpointer value, gpointer user_data)
 182 {
 183         g_debug("GritsOpenGL: _draw_level - level=%-4ld", (glong)key);
 184         GritsOpenGL *opengl = user_data;
 185         struct RenderLevel *level = value;
 186         int nsorted = 0, nunsorted = 0;
 187         GList *cur = NULL;
 188
 189         /* Draw opaque objects without sorting */
 190         glDepthMask(TRUE);
 191         glClear(GL_DEPTH_BUFFER_BIT);
 192         for (cur = level->unsorted.next; cur; cur = cur->next, nunsorted++)
 193                 grits_object_draw(GRITS_OBJECT(cur->data), opengl);
 194
 195         /* Freeze depth buffer and draw transparent objects sorted */
 196         /* TODO: sorting */
 197         //glDepthMask(FALSE);
 198         glAlphaFunc(GL_GREATER, 0.1);
 199         for (cur = level->sorted.next; cur; cur = cur->next, nsorted++)
 200                 grits_object_draw(GRITS_OBJECT(cur->data), opengl);
 201
 202         /* TODO: Prune empty levels */
 203
 204         g_debug("GritsOpenGL: _draw_level - drew %d,%d objects",
 205                         nunsorted, nsorted);
 206         return FALSE;
 207 }
 208
 209 static gboolean on_expose(GritsOpenGL *opengl, GdkEventExpose *event, gpointer _)
 210 {
 211         g_debug("GritsOpenGL: on_expose - begin");
 212
 213         glClear(GL_COLOR_BUFFER_BIT);
 214
 215         _set_visuals(opengl);
 216 #ifdef ROAM_DEBUG
 217         glColor4f(1.0, 1.0, 1.0, 1.0);
 218         glLineWidth(2);
 219         glDisable(GL_TEXTURE_2D);
 220         glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
 221         roam_sphere_draw(opengl->sphere);
 222         (void)_draw_level;
 223         //roam_sphere_draw_normals(opengl->sphere);
 224 #else
 225         g_mutex_lock(opengl->objects_lock);
 226         g_tree_foreach(opengl->objects, _draw_level, opengl);
 227         if (opengl->wireframe) {
 228                 glClear(GL_DEPTH_BUFFER_BIT);
 229                 glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
 230                 roam_sphere_draw(opengl->sphere);
 231                 g_tree_foreach(opengl->objects, _draw_level, opengl);
 232         }
 233         g_mutex_unlock(opengl->objects_lock);
 234 #endif
 235
 236         gtk_gl_end(GTK_WIDGET(opengl));
 237
 238         g_debug("GritsOpenGL: on_expose - end\n");
 239         return FALSE;
 240 }
 241
 242 static gboolean on_motion_notify(GritsOpenGL *opengl, GdkEventMotion *event, gpointer _)
 243 {
 244         gdouble height = GTK_WIDGET(opengl)->allocation.height;
 245         gdouble gl_x   = event->x;
 246         gdouble gl_y   = height - event->y;
 247
 248         /* Configure view */
 249         gint viewport[4];
 250         gdouble projection[16];
 251         glGetIntegerv(GL_VIEWPORT, viewport);
 252         glGetDoublev(GL_PROJECTION_MATRIX, projection);
 253
 254         glMatrixMode(GL_PROJECTION);
 255         glPushMatrix();
 256         glLoadIdentity();
 257         gluPickMatrix(gl_x, gl_y, 2, 2, viewport);
 258         glMultMatrixd(projection);
 259
 260         /* Prepare for picking */
 261         guint buffer[100][4] = {};
 262         glSelectBuffer(G_N_ELEMENTS(buffer), (guint*)buffer);
 263         glRenderMode(GL_SELECT);
 264         glInitNames();
 265
 266         /* Run picking */
 267         g_mutex_lock(opengl->objects_lock);
 268         GPtrArray *objects = _objects_to_array(opengl);
 269         for (guint i = 0; i < objects->len; i++) {
 270                 glPushName(i);
 271                 GritsObject *object = objects->pdata[i];
 272                 object->state.picked = FALSE;
 273                 grits_object_pick(object, opengl);
 274                 glPopName();
 275         }
 276         int hits = glRenderMode(GL_RENDER);
 277         g_debug("GritsOpenGL: on_motion_notify - hits=%d ev=%.0lf,%.0lf",
 278                         hits, gl_x, gl_y);
 279         for (int i = 0; i < hits; i++) {
 280                 //g_debug("\tHit: %d",     i);
 281                 //g_debug("\t\tcount: %d", buffer[i][0]);
 282                 //g_debug("\t\tz1:    %f", (float)buffer[i][1]/0x7fffffff);
 283                 //g_debug("\t\tz2:    %f", (float)buffer[i][2]/0x7fffffff);
 284                 //g_debug("\t\tname:  %p", (gpointer)buffer[i][3]);
 285                 guint        index  = buffer[i][3];
 286                 GritsObject *object = objects->pdata[index];
 287                 object->state.picked = TRUE;
 288         }
 289         for (guint i = 0; i < objects->len; i++) {
 290                 GritsObject *object = objects->pdata[i];
 291                 grits_object_set_pointer(object, object->state.picked);
 292         }
 293         g_ptr_array_free(objects, TRUE);
 294         g_mutex_unlock(opengl->objects_lock);
 295
 296         /* Cleanup */
 297         glMatrixMode(GL_PROJECTION);
 298         glPopMatrix();
 299
 300         return FALSE;
 301 }
 302
 303 static gboolean on_key_press(GritsOpenGL *opengl, GdkEventKey *event, gpointer _)
 304 {
 305         g_debug("GritsOpenGL: on_key_press - key=%x, state=%x, plus=%x",
 306                         event->keyval, event->state, GDK_plus);
 307
 308         guint kv = event->keyval;
 309         /* Testing */
 310         if (kv == GDK_w) {
 311                 opengl->wireframe = !opengl->wireframe;
 312                 gtk_widget_queue_draw(GTK_WIDGET(opengl));
 313         }
 314 #ifdef ROAM_DEBUG
 315         else if (kv == GDK_n) roam_sphere_split_one(opengl->sphere);
 316         else if (kv == GDK_p) roam_sphere_merge_one(opengl->sphere);
 317         else if (kv == GDK_r) roam_sphere_split_merge(opengl->sphere);
 318         else if (kv == GDK_u) roam_sphere_update_errors(opengl->sphere);
 319         gtk_widget_queue_draw(GTK_WIDGET(opengl));
 320 #endif
 321         return FALSE;
 322 }
 323
 324 static gboolean on_chained_event(GritsOpenGL *opengl, GdkEvent *event, gpointer _)
 325 {
 326         _foreach_object(opengl, (GFunc)grits_object_event, event);
 327         return FALSE;
 328 }
 329
 330 static gboolean _update_errors_cb(gpointer _opengl)
 331 {
 332         GritsOpenGL *opengl = _opengl;
 333         g_mutex_lock(opengl->sphere_lock);
 334         roam_sphere_update_errors(opengl->sphere);
 335         g_mutex_unlock(opengl->sphere_lock);
 336         opengl->ue_source = 0;
 337         return FALSE;
 338 }
 339 static void on_view_changed(GritsOpenGL *opengl,
 340                 gdouble _1, gdouble _2, gdouble _3)
 341 {
 342         g_debug("GritsOpenGL: on_view_changed");
 343         _set_visuals(opengl);
 344 #ifndef ROAM_DEBUG
 345         if (!opengl->ue_source)
 346                 opengl->ue_source = g_idle_add_full(G_PRIORITY_HIGH_IDLE+30,
 347                                 _update_errors_cb, opengl, NULL);
 348         //roam_sphere_update_errors(opengl->sphere);
 349 #else
 350         (void)_update_errors_cb;
 351 #endif
 352 }
 353
 354 static gboolean on_idle(GritsOpenGL *opengl)
 355 {
 356         //g_debug("GritsOpenGL: on_idle");
 357         g_mutex_lock(opengl->sphere_lock);
 358         if (roam_sphere_split_merge(opengl->sphere))
 359                 gtk_widget_queue_draw(GTK_WIDGET(opengl));
 360         g_mutex_unlock(opengl->sphere_lock);
 361         return TRUE;
 362 }
 363
 364 static void on_realize(GritsOpenGL *opengl, gpointer _)
 365 {
 366         g_debug("GritsOpenGL: on_realize");
 367         gtk_gl_begin(GTK_WIDGET(opengl));
 368
 369         /* Connect signals and idle functions now that opengl is fully initialized */
 370         gtk_widget_add_events(GTK_WIDGET(opengl), GDK_KEY_PRESS_MASK);
 371         g_signal_connect(opengl, "configure-event",  G_CALLBACK(on_configure),    NULL);
 372         g_signal_connect(opengl, "expose-event",     G_CALLBACK(on_expose),       NULL);
 373
 374         g_signal_connect(opengl, "key-press-event",  G_CALLBACK(on_key_press),    NULL);
 375
 376         g_signal_connect(opengl, "location-changed", G_CALLBACK(on_view_changed), NULL);
 377         g_signal_connect(opengl, "rotation-changed", G_CALLBACK(on_view_changed), NULL);
 378
 379         g_signal_connect(opengl, "motion-notify-event", G_CALLBACK(on_motion_notify), NULL);
 380         g_signal_connect_after(opengl, "key-press-event",      G_CALLBACK(on_chained_event), NULL);
 381         g_signal_connect_after(opengl, "key-release-event",    G_CALLBACK(on_chained_event), NULL);
 382         g_signal_connect_after(opengl, "button-press-event",   G_CALLBACK(on_chained_event), NULL);
 383         g_signal_connect_after(opengl, "button-release-event", G_CALLBACK(on_chained_event), NULL);
 384         g_signal_connect_after(opengl, "motion-notify-event",  G_CALLBACK(on_chained_event), NULL);
 385
 386 #ifndef ROAM_DEBUG
 387         opengl->sm_source[0] = g_timeout_add_full(G_PRIORITY_HIGH_IDLE+30, 33,  (GSourceFunc)on_idle, opengl, NULL);
 388         opengl->sm_source[1] = g_timeout_add_full(G_PRIORITY_HIGH_IDLE+10, 500, (GSourceFunc)on_idle, opengl, NULL);
 389 #else
 390         (void)on_idle;
 391         (void)_update_errors_cb;
 392 #endif
 393
 394         /* Re-queue resize incase configure was triggered before realize */
 395         gtk_widget_queue_resize(GTK_WIDGET(opengl));
 396 }
 397
 398 /*********************
 399  * GritsViewer methods *
 400  *********************/
 401 /**
 402  * grits_opengl_new:
 403  * @plugins: the plugins store to use
 404  * @prefs:   the preferences object to use
 405  *
 406  * Create a new OpenGL renderer.
 407  *
 408  * Returns: the new #GritsOpenGL
 409  */
 410 GritsViewer *grits_opengl_new(GritsPlugins *plugins, GritsPrefs *prefs)
 411 {
 412         g_debug("GritsOpenGL: new");
 413         GritsViewer *opengl = g_object_new(GRITS_TYPE_OPENGL, NULL);
 414         grits_viewer_setup(opengl, plugins, prefs);
 415         return opengl;
 416 }
 417
 418 static void grits_opengl_center_position(GritsViewer *_opengl, gdouble lat, gdouble lon, gdouble elev)
 419 {
 420         glRotatef(lon, 0, 1, 0);
 421         glRotatef(-lat, 1, 0, 0);
 422         glTranslatef(0, 0, elev2rad(elev));
 423 }
 424
 425 static void grits_opengl_project(GritsViewer *_opengl,
 426                 gdouble lat, gdouble lon, gdouble elev,
 427                 gdouble *px, gdouble *py, gdouble *pz)
 428 {
 429         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 430         gdouble x, y, z;
 431         lle2xyz(lat, lon, elev, &x, &y, &z);
 432         gluProject(x, y, z,
 433                 opengl->sphere->view->model,
 434                 opengl->sphere->view->proj,
 435                 opengl->sphere->view->view,
 436                 px, py, pz);
 437 }
 438
 439 static void grits_opengl_set_height_func(GritsViewer *_opengl, GritsBounds *bounds,
 440                 RoamHeightFunc height_func, gpointer user_data, gboolean update)
 441 {
 442         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 443         /* TODO: get points? */
 444         g_mutex_lock(opengl->sphere_lock);
 445         GList *triangles = roam_sphere_get_intersect(opengl->sphere, TRUE,
 446                         bounds->n, bounds->s, bounds->e, bounds->w);
 447         for (GList *cur = triangles; cur; cur = cur->next) {
 448                 RoamTriangle *tri = cur->data;
 449                 RoamPoint *points[] = {tri->p.l, tri->p.m, tri->p.r, tri->split};
 450                 for (int i = 0; i < G_N_ELEMENTS(points); i++) {
 451                         if (bounds->n >= points[i]->lat && points[i]->lat >= bounds->s &&
 452                             bounds->e >= points[i]->lon && points[i]->lon >= bounds->w) {
 453                                 points[i]->height_func = height_func;
 454                                 points[i]->height_data = user_data;
 455                                 roam_point_update_height(points[i]);
 456                         }
 457                 }
 458         }
 459         g_list_free(triangles);
 460         g_mutex_unlock(opengl->sphere_lock);
 461 }
 462
 463 static void _grits_opengl_clear_height_func_rec(RoamTriangle *root)
 464 {
 465         if (!root)
 466                 return;
 467         RoamPoint *points[] = {root->p.l, root->p.m, root->p.r, root->split};
 468         for (int i = 0; i < G_N_ELEMENTS(points); i++) {
 469                 points[i]->height_func = NULL;
 470                 points[i]->height_data = NULL;
 471                 roam_point_update_height(points[i]);
 472         }
 473         _grits_opengl_clear_height_func_rec(root->kids[0]);
 474         _grits_opengl_clear_height_func_rec(root->kids[1]);
 475 }
 476
 477 static void grits_opengl_clear_height_func(GritsViewer *_opengl)
 478 {
 479         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 480         for (int i = 0; i < G_N_ELEMENTS(opengl->sphere->roots); i++)
 481                 _grits_opengl_clear_height_func_rec(opengl->sphere->roots[i]);
 482 }
 483
 484 static gpointer grits_opengl_add(GritsViewer *_opengl, GritsObject *object,
 485                 gint key, gboolean sort)
 486 {
 487         g_assert(GRITS_IS_OPENGL(_opengl));
 488         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 489         g_mutex_lock(opengl->objects_lock);
 490         struct RenderLevel *level = g_tree_lookup(opengl->objects, (gpointer)(gintptr)key);
 491         if (!level) {
 492                 level = g_new0(struct RenderLevel, 1);
 493                 g_tree_insert(opengl->objects, (gpointer)(gintptr)key, level);
 494         }
 495         GList *list = sort ? &level->sorted : &level->unsorted;
 496         /* Put the link in the list */
 497         GList *link = g_new0(GList, 1);
 498         link->data = object;
 499         link->prev = list;
 500         link->next = list->next;
 501         if (list->next)
 502                 list->next->prev = link;
 503         list->next = link;
 504         g_mutex_unlock(opengl->objects_lock);
 505         return link;
 506 }
 507
 508 static GritsObject *grits_opengl_remove(GritsViewer *_opengl, GritsObject *object)
 509 {
 510         g_assert(GRITS_IS_OPENGL(_opengl));
 511         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 512         GList *link = object->ref;
 513         g_mutex_lock(opengl->objects_lock);
 514         /* Just unlink and free it, link->prev is assured */
 515         link->prev->next = link->next;
 516         if (link->next)
 517                 link->next->prev = link->prev;
 518         g_mutex_unlock(opengl->objects_lock);
 519         object->ref    = NULL;
 520         object->viewer = NULL;
 521         g_free(link);
 522         g_object_unref(object);
 523         return object;
 524 }
 525
 526 /****************
 527  * GObject code *
 528  ****************/
 529 static int _objects_cmp(gconstpointer _a, gconstpointer _b, gpointer _)
 530 {
 531         gintptr a = (gintptr)_a, b = (gintptr)_b;
 532         return a < b ? -1 :
 533                a > b ?  1 : 0;
 534 }
 535 static void _objects_free(gpointer value)
 536 {
 537         struct RenderLevel *level = value;
 538         if (level->sorted.next)
 539                 g_list_free(level->sorted.next);
 540         if (level->unsorted.next)
 541                 g_list_free(level->unsorted.next);
 542         g_free(level);
 543 }
 544
 545 G_DEFINE_TYPE(GritsOpenGL, grits_opengl, GRITS_TYPE_VIEWER);
 546 static void grits_opengl_init(GritsOpenGL *opengl)
 547 {
 548         g_debug("GritsOpenGL: init");
 549         opengl->objects      = g_tree_new_full(_objects_cmp, NULL, NULL, _objects_free);
 550         opengl->objects_lock = g_mutex_new();
 551         opengl->sphere       = roam_sphere_new(opengl);
 552         opengl->sphere_lock  = g_mutex_new();
 553         gtk_gl_enable(GTK_WIDGET(opengl));
 554         g_signal_connect(opengl, "realize", G_CALLBACK(on_realize), NULL);
 555 }
 556 static void grits_opengl_dispose(GObject *_opengl)
 557 {
 558         g_debug("GritsOpenGL: dispose");
 559         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 560         if (opengl->sm_source[0]) {
 561                 g_source_remove(opengl->sm_source[0]);
 562                 opengl->sm_source[0] = 0;
 563         }
 564         if (opengl->sm_source[1]) {
 565                 g_source_remove(opengl->sm_source[1]);
 566                 opengl->sm_source[1] = 0;
 567         }
 568         if (opengl->ue_source) {
 569                 g_source_remove(opengl->ue_source);
 570                 opengl->ue_source = 0;
 571         }
 572         G_OBJECT_CLASS(grits_opengl_parent_class)->dispose(_opengl);
 573 }
 574 static void grits_opengl_finalize(GObject *_opengl)
 575 {
 576         g_debug("GritsOpenGL: finalize");
 577         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 578         roam_sphere_free(opengl->sphere);
 579         g_tree_destroy(opengl->objects);
 580         g_mutex_free(opengl->objects_lock);
 581         g_mutex_free(opengl->sphere_lock);
 582         G_OBJECT_CLASS(grits_opengl_parent_class)->finalize(_opengl);
 583 }
 584 static void grits_opengl_class_init(GritsOpenGLClass *klass)
 585 {
 586         g_debug("GritsOpenGL: class_init");
 587         GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
 588         gobject_class->finalize = grits_opengl_finalize;
 589         gobject_class->dispose = grits_opengl_dispose;
 590
 591         GritsViewerClass *viewer_class = GRITS_VIEWER_CLASS(klass);
 592         viewer_class->center_position   = grits_opengl_center_position;
 593         viewer_class->project           = grits_opengl_project;
 594         viewer_class->clear_height_func = grits_opengl_clear_height_func;
 595         viewer_class->set_height_func   = grits_opengl_set_height_func;
 596         viewer_class->add               = grits_opengl_add;
 597         viewer_class->remove            = grits_opengl_remove;
 598 }