Pileus Git - grits/blob - src/gis-opengl.c

   1 /*
   2  * Copyright (C) 2009-2010 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:gis-opengl
  20  * @short_description: OpenGL based virtual globe
  21  *
  22  * #GisOpenGL is the core rendering engine used by libgis. Theoretically other
  23  * renderers could be writte, but they have not been. GisOpenGL uses the ROAM
  24  * algorithm for updating surface mesh the planet. The only thing GisOpenGL can
  25  * actually render on it's own is a wireframe of a sphere.
  26  *
  27  * GisOpenGL 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 "gis-opengl.h"
  40 #include "gis-util.h"
  41 #include "roam.h"
  42
  43 #include "objects/gis-object.h"
  44 #include "objects/gis-marker.h"
  45 #include "objects/gis-callback.h"
  46
  47 // #define ROAM_DEBUG
  48
  49 /* Tessellation, "finding intersecting triangles" */
  50 /* http://research.microsoft.com/pubs/70307/tr-2006-81.pdf */
  51 /* http://www.opengl.org/wiki/Alpha_Blending */
  52
  53 /***********
  54  * Helpers *
  55  ***********/
  56 static void _set_visuals(GisOpenGL *opengl)
  57 {
  58         glMatrixMode(GL_MODELVIEW);
  59         glLoadIdentity();
  60
  61         /* Camera 1 */
  62         double lat, lon, elev, rx, ry, rz;
  63         gis_viewer_get_location(GIS_VIEWER(opengl), &lat, &lon, &elev);
  64         gis_viewer_get_rotation(GIS_VIEWER(opengl), &rx, &ry, &rz);
  65         glRotatef(rx, 1, 0, 0);
  66         glRotatef(rz, 0, 0, 1);
  67
  68         /* Lighting */
  69 #ifdef ROAM_DEBUG
  70         float light_ambient[]  = {0.7f, 0.7f, 0.7f, 1.0f};
  71         float light_diffuse[]  = {2.0f, 2.0f, 2.0f, 1.0f};
  72 #else
  73         float light_ambient[]  = {0.2f, 0.2f, 0.2f, 1.0f};
  74         float light_diffuse[]  = {5.0f, 5.0f, 5.0f, 1.0f};
  75 #endif
  76         float light_position[] = {-13*EARTH_R, 1*EARTH_R, 3*EARTH_R, 1.0f};
  77         glLightfv(GL_LIGHT0, GL_AMBIENT,  light_ambient);
  78         glLightfv(GL_LIGHT0, GL_DIFFUSE,  light_diffuse);
  79         glLightfv(GL_LIGHT0, GL_POSITION, light_position);
  80         glEnable(GL_LIGHT0);
  81         glEnable(GL_LIGHTING);
  82
  83         float material_ambient[]  = {0.2, 0.2, 0.2, 1.0};
  84         float material_diffuse[]  = {0.8, 0.8, 0.8, 1.0};
  85         float material_specular[] = {0.1, 0.1, 0.1, 1.0};
  86         float material_emission[] = {0.0, 0.0, 0.0, 1.0};
  87         glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT,  material_ambient);
  88         glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE,  material_diffuse);
  89         glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, material_specular);
  90         glMaterialfv(GL_FRONT_AND_BACK, GL_EMISSION, material_emission);
  91         glDisable(GL_TEXTURE_2D);
  92         glDisable(GL_COLOR_MATERIAL);
  93
  94         /* Camera 2 */
  95         glTranslatef(0, 0, -elev2rad(elev));
  96         glRotatef(lat, 1, 0, 0);
  97         glRotatef(-lon, 0, 1, 0);
  98
  99         glDisable(GL_ALPHA_TEST);
 100
 101         glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 102         glEnable(GL_BLEND);
 103
 104 #ifndef ROAM_DEBUG
 105         glCullFace(GL_BACK);
 106         glEnable(GL_CULL_FACE);
 107 #endif
 108
 109         glClearDepth(1.0);
 110         glDepthFunc(GL_LEQUAL);
 111         glEnable(GL_DEPTH_TEST);
 112
 113         glEnable(GL_LINE_SMOOTH);
 114
 115         glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
 116         //glShadeModel(GL_FLAT);
 117
 118         roam_sphere_update_view(opengl->sphere);
 119 }
 120
 121
 122 /********************
 123  * Object handleing *
 124  ********************/
 125 static void _draw_tile(GisOpenGL *opengl, GisTile *tile)
 126 {
 127         if (!tile || !tile->data)
 128                 return;
 129         GList *triangles = roam_sphere_get_intersect(opengl->sphere, FALSE,
 130                         tile->edge.n, tile->edge.s, tile->edge.e, tile->edge.w);
 131         if (!triangles)
 132                 g_warning("GisOpenGL: _draw_tiles - No triangles to draw: edges=%f,%f,%f,%f",
 133                         tile->edge.n, tile->edge.s, tile->edge.e, tile->edge.w);
 134         //g_message("drawing %4d triangles for tile edges=%7.2f,%7.2f,%7.2f,%7.2f",
 135         //              g_list_length(triangles), tile->edge.n, tile->edge.s, tile->edge.e, tile->edge.w);
 136         for (GList *cur = triangles; cur; cur = cur->next) {
 137                 RoamTriangle *tri = cur->data;
 138
 139                 gdouble lat[3] = {tri->p.r->lat, tri->p.m->lat, tri->p.l->lat};
 140                 gdouble lon[3] = {tri->p.r->lon, tri->p.m->lon, tri->p.l->lon};
 141
 142                 if (lon[0] < -90 || lon[1] < -90 || lon[2] < -90) {
 143                         if (lon[0] > 90) lon[0] -= 360;
 144                         if (lon[1] > 90) lon[1] -= 360;
 145                         if (lon[2] > 90) lon[2] -= 360;
 146                 }
 147
 148                 gdouble n = tile->edge.n;
 149                 gdouble s = tile->edge.s;
 150                 gdouble e = tile->edge.e;
 151                 gdouble w = tile->edge.w;
 152
 153                 gdouble londist = e - w;
 154                 gdouble latdist = n - s;
 155
 156                 gdouble xy[3][2] = {
 157                         {(lon[0]-w)/londist, 1-(lat[0]-s)/latdist},
 158                         {(lon[1]-w)/londist, 1-(lat[1]-s)/latdist},
 159                         {(lon[2]-w)/londist, 1-(lat[2]-s)/latdist},
 160                 };
 161
 162                 //if ((lat[0] == 90 && (xy[0][0] < 0 || xy[0][0] > 1)) ||
 163                 //    (lat[1] == 90 && (xy[1][0] < 0 || xy[1][0] > 1)) ||
 164                 //    (lat[2] == 90 && (xy[2][0] < 0 || xy[2][0] > 1)))
 165                 //      g_message("w,e=%4.f,%4.f   "
 166                 //                "lat,lon,x,y="
 167                 //                "%4.1f,%4.0f,%4.2f,%4.2f   "
 168                 //                "%4.1f,%4.0f,%4.2f,%4.2f   "
 169                 //                "%4.1f,%4.0f,%4.2f,%4.2f   ",
 170                 //              w,e,
 171                 //              lat[0], lon[0], xy[0][0], xy[0][1],
 172                 //              lat[1], lon[1], xy[1][0], xy[1][1],
 173                 //              lat[2], lon[2], xy[2][0], xy[2][1]);
 174
 175                 /* Fix poles */
 176                 if (lat[0] == 90 || lat[0] == -90) xy[0][0] = 0.5;
 177                 if (lat[1] == 90 || lat[1] == -90) xy[1][0] = 0.5;
 178                 if (lat[2] == 90 || lat[2] == -90) xy[2][0] = 0.5;
 179
 180                 glEnable(GL_TEXTURE_2D);
 181                 glBindTexture(GL_TEXTURE_2D, *(guint*)tile->data);
 182                 glBegin(GL_TRIANGLES);
 183                 glNormal3dv(tri->p.r->norm); glTexCoord2dv(xy[0]); glVertex3dv((double*)tri->p.r);
 184                 glNormal3dv(tri->p.m->norm); glTexCoord2dv(xy[1]); glVertex3dv((double*)tri->p.m);
 185                 glNormal3dv(tri->p.l->norm); glTexCoord2dv(xy[2]); glVertex3dv((double*)tri->p.l);
 186                 glEnd();
 187         }
 188         g_list_free(triangles);
 189 }
 190
 191 static void _draw_tiles(GisOpenGL *opengl, GisTile *tile)
 192 {
 193         /* Only draw children if possible */
 194         gboolean has_children = TRUE;
 195         GisTile *child;
 196         gis_tile_foreach(tile, child)
 197                 if (!child || !child->data)
 198                         has_children = FALSE;
 199         if (has_children)
 200                 /* Only draw children */
 201                 gis_tile_foreach(tile, child)
 202                         _draw_tiles(opengl, child);
 203         else
 204                 /* No children, draw this tile */
 205                 _draw_tile(opengl, tile);
 206 }
 207
 208 static void _draw_marker(GisOpenGL *opengl, GisMarker *marker)
 209 {
 210         GisPoint *point = gis_object_center(marker);
 211         gdouble px, py, pz;
 212         gis_viewer_project(GIS_VIEWER(opengl),
 213                         point->lat, point->lon, point->elev,
 214                         &px, &py, &pz);
 215         if (pz > 1)
 216                 return;
 217
 218         //g_debug("GisOpenGL: draw_marker - %s pz=%f ", marker->label, pz);
 219
 220         cairo_surface_t *surface = cairo_get_target(marker->cairo);
 221         gdouble width  = cairo_image_surface_get_width(surface);
 222         gdouble height = cairo_image_surface_get_height(surface);
 223
 224         glMatrixMode(GL_PROJECTION); glLoadIdentity();
 225         glMatrixMode(GL_MODELVIEW);  glLoadIdentity();
 226         glOrtho(0, GTK_WIDGET(opengl)->allocation.width,
 227                 0, GTK_WIDGET(opengl)->allocation.height, -1, 1);
 228         glTranslated(px - marker->xoff,
 229                      py - marker->yoff, 0);
 230
 231         glDisable(GL_LIGHTING);
 232         glDisable(GL_COLOR_MATERIAL);
 233         glDisable(GL_DEPTH_TEST);
 234         glEnable(GL_TEXTURE_2D);
 235         glBindTexture(GL_TEXTURE_2D, marker->tex);
 236         glBegin(GL_QUADS);
 237         glTexCoord2f(1, 1); glVertex3f(width, 0     , 0);
 238         glTexCoord2f(1, 0); glVertex3f(width, height, 0);
 239         glTexCoord2f(0, 0); glVertex3f(0    , height, 0);
 240         glTexCoord2f(0, 1); glVertex3f(0    , 0     , 0);
 241         glEnd();
 242 }
 243
 244 static void _draw_callback(GisOpenGL *opengl, GisCallback *callback)
 245 {
 246         callback->callback(callback, callback->user_data);
 247 }
 248
 249 static void _draw_object(GisOpenGL *opengl, GisObject *object)
 250 {
 251         //g_debug("GisOpenGL: draw_object");
 252         /* Skip out of range objects */
 253         if (object->lod > 0) {
 254                 gdouble eye[3], obj[3];
 255                 gis_viewer_get_location(GIS_VIEWER(opengl), &eye[0], &eye[1], &eye[2]);
 256                 lle2xyz(eye[0], eye[1], eye[2], &eye[0], &eye[1], &eye[2]);
 257                 lle2xyz(object->center.lat, object->center.lon, object->center.elev,
 258                         &obj[0], &obj[1], &obj[2]);
 259                 gdouble dist = distd(obj, eye);
 260                 if (object->lod < dist)
 261                         return;
 262         }
 263
 264         /* Draw */
 265         glMatrixMode(GL_PROJECTION); glPushMatrix();
 266         glMatrixMode(GL_MODELVIEW);  glPushMatrix();
 267         glPushAttrib(GL_ALL_ATTRIB_BITS);
 268         if (GIS_IS_MARKER(object)) {
 269                 _draw_marker(opengl, GIS_MARKER(object));
 270         } else if (GIS_IS_CALLBACK(object)) {
 271                 _draw_callback(opengl, GIS_CALLBACK(object));
 272         } else if (GIS_IS_TILE(object)) {
 273                 _draw_tiles(opengl, GIS_TILE(object));
 274         }
 275         glPopAttrib();
 276         glMatrixMode(GL_PROJECTION); glPopMatrix();
 277         glMatrixMode(GL_MODELVIEW);  glPopMatrix();
 278 }
 279
 280 static void _load_object(GisOpenGL *opengl, GisObject *object)
 281 {
 282         g_debug("GisOpenGL: load_object");
 283         if (GIS_IS_MARKER(object)) {
 284                 GisMarker *marker = GIS_MARKER(object);
 285                 cairo_surface_t *surface = cairo_get_target(marker->cairo);
 286                 gdouble width  = cairo_image_surface_get_width(surface);
 287                 gdouble height = cairo_image_surface_get_height(surface);
 288
 289                 glEnable(GL_TEXTURE_2D);
 290                 glGenTextures(1, &marker->tex);
 291                 glBindTexture(GL_TEXTURE_2D, marker->tex);
 292
 293                 glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
 294                 glPixelStorei(GL_PACK_ALIGNMENT, 1);
 295                 glTexImage2D(GL_TEXTURE_2D, 0, 4, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE,
 296                                 cairo_image_surface_get_data(surface));
 297                 glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 298                 glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 299                 g_debug("load_texture: %d", marker->tex);
 300         }
 301 }
 302
 303 static void _unload_object(GisOpenGL *opengl, GisObject *object)
 304 {
 305         g_debug("GisOpenGL: unload_object");
 306         if (GIS_IS_MARKER(object)) {
 307                 GisMarker *marker = GIS_MARKER(object);
 308                 glDeleteTextures(1, &marker->tex);
 309         }
 310 }
 311
 312
 313 /*************
 314  * Callbacks *
 315  *************/
 316 /* The unsorted/sroted GLists are blank head nodes,
 317  * This way us we can remove objects from the level just by fixing up links
 318  * I.e. we don't need to do a lookup to remove an object if we have its GList */
 319 struct RenderLevel {
 320         GList unsorted;
 321         GList sorted;
 322 };
 323
 324 static void on_realize(GisOpenGL *opengl, gpointer _)
 325 {
 326         g_debug("GisOpenGL: on_realize");
 327
 328         GdkGLContext   *glcontext  = gtk_widget_get_gl_context(GTK_WIDGET(opengl));
 329         GdkGLDrawable  *gldrawable = gtk_widget_get_gl_drawable(GTK_WIDGET(opengl));
 330         if (!gdk_gl_drawable_gl_begin(gldrawable, glcontext))
 331                 g_assert_not_reached();
 332
 333         _set_visuals(opengl);
 334         g_mutex_lock(opengl->sphere_lock);
 335         roam_sphere_update_errors(opengl->sphere);
 336         g_mutex_unlock(opengl->sphere_lock);
 337 }
 338
 339 static gboolean on_configure(GisOpenGL *opengl, GdkEventConfigure *event, gpointer _)
 340 {
 341         g_debug("GisOpenGL: on_configure");
 342
 343         double width  = GTK_WIDGET(opengl)->allocation.width;
 344         double height = GTK_WIDGET(opengl)->allocation.height;
 345
 346         /* Setup OpenGL Window */
 347         glViewport(0, 0, width, height);
 348         glMatrixMode(GL_PROJECTION);
 349         glLoadIdentity();
 350         double ang = atan(height/FOV_DIST);
 351         gluPerspective(rad2deg(ang)*2, width/height, 1, 10*EARTH_R);
 352
 353 #ifndef ROAM_DEBUG
 354         g_mutex_lock(opengl->sphere_lock);
 355         roam_sphere_update_errors(opengl->sphere);
 356         g_mutex_unlock(opengl->sphere_lock);
 357 #endif
 358
 359         return FALSE;
 360 }
 361
 362 static gboolean _draw_level(gpointer key, gpointer value, gpointer user_data)
 363 {
 364         g_debug("GisOpenGL: _draw_level - level=%-4d", (int)key);
 365         GisOpenGL *opengl = user_data;
 366         struct RenderLevel *level = value;
 367         int nsorted = 0, nunsorted = 0;
 368         GList *cur = NULL;
 369
 370         /* Draw opaque objects without sorting */
 371         glDepthMask(TRUE);
 372         glClear(GL_DEPTH_BUFFER_BIT);
 373         for (cur = level->unsorted.next; cur; cur = cur->next, nunsorted++)
 374                 _draw_object(opengl, GIS_OBJECT(cur->data));
 375
 376         /* Freeze depth buffer and draw transparent objects sorted */
 377         /* TODO: sorting */
 378         //glDepthMask(FALSE);
 379         glAlphaFunc(GL_GREATER, 0.1);
 380         for (cur = level->sorted.next; cur; cur = cur->next, nsorted++)
 381                 _draw_object(opengl, GIS_OBJECT(cur->data));
 382
 383         /* TODO: Prune empty levels */
 384
 385         g_debug("GisOpenGL: _draw_level - drew %d,%d objects",
 386                         nunsorted, nsorted);
 387         return FALSE;
 388 }
 389
 390 static gboolean on_expose(GisOpenGL *opengl, GdkEventExpose *event, gpointer _)
 391 {
 392         g_debug("GisOpenGL: on_expose - begin");
 393
 394         glClear(GL_COLOR_BUFFER_BIT);
 395
 396         _set_visuals(opengl);
 397 #ifdef ROAM_DEBUG
 398         glColor4f(0.0, 0.0, 9.0, 0.6);
 399         glDisable(GL_TEXTURE_2D);
 400         glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
 401         roam_sphere_draw(opengl->sphere);
 402         //roam_sphere_draw_normals(opengl->sphere);
 403 #else
 404         g_tree_foreach(opengl->objects, _draw_level, opengl);
 405         if (opengl->wireframe) {
 406                 glClear(GL_DEPTH_BUFFER_BIT);
 407                 glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
 408                 roam_sphere_draw(opengl->sphere);
 409         }
 410 #endif
 411
 412         GdkGLDrawable *gldrawable = gtk_widget_get_gl_drawable(GTK_WIDGET(opengl));
 413         gdk_gl_drawable_swap_buffers(gldrawable);
 414
 415         g_debug("GisOpenGL: on_expose - end\n");
 416         return FALSE;
 417 }
 418
 419 static gboolean on_key_press(GisOpenGL *opengl, GdkEventKey *event, gpointer _)
 420 {
 421         g_debug("GisOpenGL: on_key_press - key=%x, state=%x, plus=%x",
 422                         event->keyval, event->state, GDK_plus);
 423
 424         guint kv = event->keyval;
 425         gdk_threads_leave();
 426         /* Testing */
 427         if (kv == GDK_w) {
 428                 opengl->wireframe = !opengl->wireframe;
 429                 gtk_widget_queue_draw(GTK_WIDGET(opengl));
 430         }
 431 #ifdef ROAM_DEBUG
 432         else if (kv == GDK_n) roam_sphere_split_one(opengl->sphere);
 433         else if (kv == GDK_p) roam_sphere_merge_one(opengl->sphere);
 434         else if (kv == GDK_r) roam_sphere_split_merge(opengl->sphere);
 435         else if (kv == GDK_u) roam_sphere_update_errors(opengl->sphere);
 436         gdk_threads_enter();
 437         gtk_widget_queue_draw(GTK_WIDGET(opengl));
 438 #else
 439         gdk_threads_enter();
 440 #endif
 441         return FALSE;
 442 }
 443
 444 static gboolean _update_errors_cb(gpointer sphere)
 445 {
 446         roam_sphere_update_errors(sphere);
 447         return FALSE;
 448 }
 449 static void on_view_changed(GisOpenGL *opengl,
 450                 gdouble _1, gdouble _2, gdouble _3)
 451 {
 452         g_debug("GisOpenGL: on_view_changed");
 453         _set_visuals(opengl);
 454 #ifndef ROAM_DEBUG
 455         opengl->ue_source = g_idle_add_full(G_PRIORITY_HIGH_IDLE+30,
 456                         _update_errors_cb, opengl->sphere, NULL);
 457         //roam_sphere_update_errors(opengl->sphere);
 458 #endif
 459 }
 460
 461 static gboolean on_idle(GisOpenGL *opengl)
 462 {
 463         //g_debug("GisOpenGL: on_idle");
 464         gdk_threads_enter();
 465         g_mutex_lock(opengl->sphere_lock);
 466         if (roam_sphere_split_merge(opengl->sphere))
 467                 gtk_widget_queue_draw(GTK_WIDGET(opengl));
 468         g_mutex_unlock(opengl->sphere_lock);
 469         gdk_threads_leave();
 470         return TRUE;
 471 }
 472
 473
 474 /*********************
 475  * GisViewer methods *
 476  *********************/
 477 /**
 478  * gis_opengl_new:
 479  * @plugins: the plugins store to use
 480  * @prefs:   the preferences object to use
 481  *
 482  * Create a new OpenGL renderer.
 483  *
 484  * Returns: the new #GisOpenGL
 485  */
 486 GisViewer *gis_opengl_new(GisPlugins *plugins, GisPrefs *prefs)
 487 {
 488         g_debug("GisOpenGL: new");
 489         GisViewer *opengl = g_object_new(GIS_TYPE_OPENGL, NULL);
 490         gis_viewer_setup(opengl, plugins, prefs);
 491         return opengl;
 492 }
 493
 494 static void gis_opengl_center_position(GisViewer *_opengl, gdouble lat, gdouble lon, gdouble elev)
 495 {
 496         GisOpenGL *opengl = GIS_OPENGL(_opengl);
 497         glRotatef(lon, 0, 1, 0);
 498         glRotatef(-lat, 1, 0, 0);
 499         glTranslatef(0, 0, elev2rad(elev));
 500 }
 501
 502 static void gis_opengl_project(GisViewer *_opengl,
 503                 gdouble lat, gdouble lon, gdouble elev,
 504                 gdouble *px, gdouble *py, gdouble *pz)
 505 {
 506         GisOpenGL *opengl = GIS_OPENGL(_opengl);
 507         gdouble x, y, z;
 508         lle2xyz(lat, lon, elev, &x, &y, &z);
 509         gluProject(x, y, z,
 510                 opengl->sphere->view->model,
 511                 opengl->sphere->view->proj,
 512                 opengl->sphere->view->view,
 513                 px, py, pz);
 514 }
 515
 516 static void gis_opengl_set_height_func(GisViewer *_opengl, GisTile *tile,
 517                 RoamHeightFunc height_func, gpointer user_data, gboolean update)
 518 {
 519         GisOpenGL *opengl = GIS_OPENGL(_opengl);
 520         if (!tile)
 521                 return;
 522         /* TODO: get points? */
 523         g_mutex_lock(opengl->sphere_lock);
 524         GList *triangles = roam_sphere_get_intersect(opengl->sphere, TRUE,
 525                         tile->edge.n, tile->edge.s, tile->edge.e, tile->edge.w);
 526         for (GList *cur = triangles; cur; cur = cur->next) {
 527                 RoamTriangle *tri = cur->data;
 528                 RoamPoint *points[] = {tri->p.l, tri->p.m, tri->p.r, tri->split};
 529                 for (int i = 0; i < G_N_ELEMENTS(points); i++) {
 530                         if (tile->edge.n >= points[i]->lat && points[i]->lat >= tile->edge.s &&
 531                             tile->edge.e >= points[i]->lon && points[i]->lon >= tile->edge.w) {
 532                                 points[i]->height_func = height_func;
 533                                 points[i]->height_data = user_data;
 534                                 roam_point_update_height(points[i]);
 535                         }
 536                 }
 537         }
 538         g_list_free(triangles);
 539         g_mutex_unlock(opengl->sphere_lock);
 540 }
 541
 542 static void _gis_opengl_clear_height_func_rec(RoamTriangle *root)
 543 {
 544         if (!root)
 545                 return;
 546         RoamPoint *points[] = {root->p.l, root->p.m, root->p.r, root->split};
 547         for (int i = 0; i < G_N_ELEMENTS(points); i++) {
 548                 points[i]->height_func = NULL;
 549                 points[i]->height_data = NULL;
 550                 roam_point_update_height(points[i]);
 551         }
 552         _gis_opengl_clear_height_func_rec(root->kids[0]);
 553         _gis_opengl_clear_height_func_rec(root->kids[1]);
 554 }
 555
 556 static void gis_opengl_clear_height_func(GisViewer *_opengl)
 557 {
 558         GisOpenGL *opengl = GIS_OPENGL(_opengl);
 559         for (int i = 0; i < G_N_ELEMENTS(opengl->sphere->roots); i++)
 560                 _gis_opengl_clear_height_func_rec(opengl->sphere->roots[i]);
 561 }
 562
 563 static gpointer gis_opengl_add(GisViewer *_opengl, GisObject *object,
 564                 gint key, gboolean sort)
 565 {
 566         g_assert(GIS_IS_OPENGL(_opengl));
 567         GisOpenGL *opengl = GIS_OPENGL(_opengl);
 568         _load_object(opengl, object);
 569         struct RenderLevel *level = g_tree_lookup(opengl->objects, (gpointer)key);
 570         if (!level) {
 571                 level = g_new0(struct RenderLevel, 1);
 572                 g_tree_insert(opengl->objects, (gpointer)key, level);
 573         }
 574         GList *list = sort ? &level->sorted : &level->unsorted;
 575         /* Put the link in the list */
 576         GList *next = g_new0(GList, 1);
 577         next->data = object;
 578         next->prev = list;
 579         next->next = list->next;
 580         list->next = next;
 581         return next;
 582 }
 583
 584 static GisObject *gis_opengl_remove(GisViewer *_opengl, gpointer _link)
 585 {
 586         g_assert(GIS_IS_OPENGL(_opengl));
 587         GisOpenGL *opengl = GIS_OPENGL(_opengl);
 588         GList *link = _link;
 589         GisObject *object = link->data;
 590         _unload_object(opengl, object);
 591         /* Just unlink and free it, link->prev is assured */
 592         link->prev->next = link->next;
 593         if (link->next)
 594                 link->next->prev = link->prev;
 595         g_free(link);
 596         g_object_unref(object);
 597         return object;
 598 }
 599
 600 /****************
 601  * GObject code *
 602  ****************/
 603 static int _objects_cmp(gconstpointer _a, gconstpointer _b, gpointer _)
 604 {
 605         gint a = (int)_a, b = (int)_b;
 606         return a < b ? -1 :
 607                a > b ?  1 : 0;
 608 }
 609 static void _objects_free(gpointer value)
 610 {
 611         struct RenderLevel *level = value;
 612         if (level->sorted.next)
 613                 g_list_free(level->sorted.next);
 614         if (level->unsorted.next)
 615                 g_list_free(level->unsorted.next);
 616         g_free(level);
 617 }
 618
 619 G_DEFINE_TYPE(GisOpenGL, gis_opengl, GIS_TYPE_VIEWER);
 620 static void gis_opengl_init(GisOpenGL *opengl)
 621 {
 622         g_debug("GisOpenGL: init");
 623         /* OpenGL setup */
 624         GdkGLConfig *glconfig = gdk_gl_config_new_by_mode(
 625                         GDK_GL_MODE_RGBA   | GDK_GL_MODE_DEPTH |
 626                         GDK_GL_MODE_DOUBLE | GDK_GL_MODE_ALPHA);
 627         if (!glconfig)
 628                 g_error("Failed to create glconfig");
 629         if (!gtk_widget_set_gl_capability(GTK_WIDGET(opengl),
 630                                 glconfig, NULL, TRUE, GDK_GL_RGBA_TYPE))
 631                 g_error("GL lacks required capabilities");
 632         g_object_unref(glconfig);
 633
 634         opengl->objects = g_tree_new_full(_objects_cmp, NULL, NULL, _objects_free);
 635         opengl->sphere = roam_sphere_new(opengl);
 636         opengl->sphere_lock = g_mutex_new();
 637
 638 #ifndef ROAM_DEBUG
 639         opengl->sm_source[0] = g_timeout_add_full(G_PRIORITY_HIGH_IDLE+30, 33,  (GSourceFunc)on_idle, opengl, NULL);
 640         opengl->sm_source[1] = g_timeout_add_full(G_PRIORITY_HIGH_IDLE+10, 500, (GSourceFunc)on_idle, opengl, NULL);
 641 #endif
 642
 643         gtk_widget_add_events(GTK_WIDGET(opengl), GDK_KEY_PRESS_MASK);
 644         g_signal_connect(opengl, "realize",          G_CALLBACK(on_realize),      NULL);
 645         g_signal_connect(opengl, "configure-event",  G_CALLBACK(on_configure),    NULL);
 646         g_signal_connect(opengl, "expose-event",     G_CALLBACK(on_expose),       NULL);
 647
 648         g_signal_connect(opengl, "key-press-event",  G_CALLBACK(on_key_press),    NULL);
 649
 650         g_signal_connect(opengl, "location-changed", G_CALLBACK(on_view_changed), NULL);
 651         g_signal_connect(opengl, "rotation-changed", G_CALLBACK(on_view_changed), NULL);
 652 }
 653 static void gis_opengl_dispose(GObject *_opengl)
 654 {
 655         g_debug("GisOpenGL: dispose");
 656         GisOpenGL *opengl = GIS_OPENGL(_opengl);
 657         if (opengl->sm_source[0]) {
 658                 g_source_remove(opengl->sm_source[0]);
 659                 opengl->sm_source[0] = 0;
 660         }
 661         if (opengl->sm_source[1]) {
 662                 g_source_remove(opengl->sm_source[1]);
 663                 opengl->sm_source[1] = 0;
 664         }
 665         if (opengl->ue_source) {
 666                 g_source_remove(opengl->ue_source);
 667                 opengl->ue_source = 0;
 668         }
 669         G_OBJECT_CLASS(gis_opengl_parent_class)->dispose(_opengl);
 670 }
 671 static void gis_opengl_finalize(GObject *_opengl)
 672 {
 673         g_debug("GisOpenGL: finalize");
 674         GisOpenGL *opengl = GIS_OPENGL(_opengl);
 675         roam_sphere_free(opengl->sphere);
 676         g_tree_destroy(opengl->objects);
 677         g_mutex_free(opengl->sphere_lock);
 678         G_OBJECT_CLASS(gis_opengl_parent_class)->finalize(_opengl);
 679 }
 680 static void gis_opengl_class_init(GisOpenGLClass *klass)
 681 {
 682         g_debug("GisOpenGL: class_init");
 683         GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
 684         gobject_class->finalize = gis_opengl_finalize;
 685         gobject_class->dispose = gis_opengl_dispose;
 686
 687         GisViewerClass *viewer_class = GIS_VIEWER_CLASS(klass);
 688         viewer_class->center_position   = gis_opengl_center_position;
 689         viewer_class->project           = gis_opengl_project;
 690         viewer_class->clear_height_func = gis_opengl_clear_height_func;
 691         viewer_class->set_height_func   = gis_opengl_set_height_func;
 692         viewer_class->add               = gis_opengl_add;
 693         viewer_class->remove            = gis_opengl_remove;
 694 }