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