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 /* Tessellation, "finding intersecting triangles" */
  19 /* http://research.microsoft.com/pubs/70307/tr-2006-81.pdf */
  20 /* http://www.opengl.org/wiki/Alpha_Blending */
  21
  22 #include <config.h>
  23 #include <math.h>
  24 #include <string.h>
  25 #include <gdk/gdkkeysyms.h>
  26 #include <gtk/gtk.h>
  27 #include <gtk/gtkgl.h>
  28 #include <GL/gl.h>
  29 #include <GL/glu.h>
  30
  31 #include "gis-opengl.h"
  32 #include "gis-util.h"
  33 #include "gis-object.h"
  34 #include "roam.h"
  35
  36 #define FOV_DIST   2000.0
  37 #define MPPX(dist) (4*dist/FOV_DIST)
  38
  39 // #define ROAM_DEBUG
  40
  41 /***********
  42  * Helpers *
  43  ***********/
  44 static void _gis_opengl_begin(GisOpenGL *self)
  45 {
  46         g_assert(GIS_IS_OPENGL(self));
  47
  48         GdkGLContext   *glcontext  = gtk_widget_get_gl_context(GTK_WIDGET(self));
  49         GdkGLDrawable  *gldrawable = gtk_widget_get_gl_drawable(GTK_WIDGET(self));
  50
  51         if (!gdk_gl_drawable_gl_begin(gldrawable, glcontext))
  52                 g_assert_not_reached();
  53 }
  54
  55 static void _gis_opengl_end(GisOpenGL *self)
  56 {
  57         g_assert(GIS_IS_OPENGL(self));
  58         GdkGLDrawable *gldrawable = gtk_widget_get_gl_drawable(GTK_WIDGET(self));
  59         gdk_gl_drawable_gl_end(gldrawable);
  60 }
  61
  62 static void _set_visuals(GisOpenGL *self)
  63 {
  64         glMatrixMode(GL_MODELVIEW);
  65         glLoadIdentity();
  66
  67         /* Camera 1 */
  68         double lat, lon, elev, rx, ry, rz;
  69         gis_viewer_get_location(GIS_VIEWER(self), &lat, &lon, &elev);
  70         gis_viewer_get_rotation(GIS_VIEWER(self), &rx, &ry, &rz);
  71         glRotatef(rx, 1, 0, 0);
  72         glRotatef(rz, 0, 0, 1);
  73
  74         /* Lighting */
  75 #ifdef ROAM_DEBUG
  76         float light_ambient[]  = {0.7f, 0.7f, 0.7f, 1.0f};
  77         float light_diffuse[]  = {2.0f, 2.0f, 2.0f, 1.0f};
  78 #else
  79         float light_ambient[]  = {0.2f, 0.2f, 0.2f, 1.0f};
  80         float light_diffuse[]  = {5.0f, 5.0f, 5.0f, 1.0f};
  81 #endif
  82         float light_position[] = {-13*EARTH_R, 1*EARTH_R, 3*EARTH_R, 1.0f};
  83         glLightfv(GL_LIGHT0, GL_AMBIENT,  light_ambient);
  84         glLightfv(GL_LIGHT0, GL_DIFFUSE,  light_diffuse);
  85         glLightfv(GL_LIGHT0, GL_POSITION, light_position);
  86         glEnable(GL_LIGHT0);
  87         glEnable(GL_LIGHTING);
  88
  89         float material_ambient[]  = {0.2, 0.2, 0.2, 1.0};
  90         float material_diffuse[]  = {0.8, 0.8, 0.8, 1.0};
  91         float material_specular[] = {0.1, 0.1, 0.1, 1.0};
  92         float material_emission[] = {0.0, 0.0, 0.0, 1.0};
  93         glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT,  material_ambient);
  94         glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE,  material_diffuse);
  95         glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, material_specular);
  96         glMaterialfv(GL_FRONT_AND_BACK, GL_EMISSION, material_emission);
  97         glDisable(GL_TEXTURE_2D);
  98         glDisable(GL_COLOR_MATERIAL);
  99
 100         /* Camera 2 */
 101         glTranslatef(0, 0, -elev2rad(elev));
 102         glRotatef(lat, 1, 0, 0);
 103         glRotatef(-lon, 0, 1, 0);
 104
 105         glDisable(GL_ALPHA_TEST);
 106
 107         glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 108         glEnable(GL_BLEND);
 109
 110 #ifndef ROAM_DEBUG
 111         glCullFace(GL_BACK);
 112         glEnable(GL_CULL_FACE);
 113 #endif
 114
 115         glClearDepth(1.0);
 116         glDepthFunc(GL_LEQUAL);
 117         glEnable(GL_DEPTH_TEST);
 118
 119         glEnable(GL_LINE_SMOOTH);
 120
 121         glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
 122         //glShadeModel(GL_FLAT);
 123
 124         roam_sphere_update_view(self->sphere);
 125 }
 126
 127
 128 /********************
 129  * Object handleing *
 130  ********************/
 131 static void _draw_marker(GisOpenGL *self, GisMarker *marker)
 132 {
 133         GisPoint *point = gis_object_center(GIS_OBJECT(marker));
 134         gdouble px, py, pz;
 135         gis_viewer_project(GIS_VIEWER(self),
 136                         point->lat, point->lon, point->elev,
 137                         &px, &py, &pz);
 138         if (pz > 1)
 139                 return;
 140
 141         //g_debug("GisOpenGL: draw_marker - %s pz=%f ", marker->label, pz);
 142
 143         cairo_surface_t *surface = cairo_get_target(marker->cairo);
 144         gdouble width  = cairo_image_surface_get_width(surface);
 145         gdouble height = cairo_image_surface_get_height(surface);
 146
 147         glMatrixMode(GL_PROJECTION); glLoadIdentity();
 148         glMatrixMode(GL_MODELVIEW);  glLoadIdentity();
 149         glOrtho(0, GTK_WIDGET(self)->allocation.width,
 150                 0, GTK_WIDGET(self)->allocation.height, -1, 1);
 151         glTranslated(px - marker->xoff,
 152                      py - marker->yoff, 0);
 153
 154         glDisable(GL_LIGHTING);
 155         glDisable(GL_COLOR_MATERIAL);
 156         glDisable(GL_DEPTH_TEST);
 157         glEnable(GL_TEXTURE_2D);
 158         glBindTexture(GL_TEXTURE_2D, marker->tex);
 159         glBegin(GL_QUADS);
 160         glTexCoord2f(1, 1); glVertex3f(width, 0     , 0);
 161         glTexCoord2f(1, 0); glVertex3f(width, height, 0);
 162         glTexCoord2f(0, 0); glVertex3f(0    , height, 0);
 163         glTexCoord2f(0, 1); glVertex3f(0    , 0     , 0);
 164         glEnd();
 165 }
 166
 167 static void _draw_callback(GisOpenGL *self, GisCallback *callback)
 168 {
 169         callback->callback(callback, callback->user_data);
 170 }
 171
 172 static void _draw_object(GisOpenGL *self, GisObject *object)
 173 {
 174         //g_debug("GisOpenGL: draw_object");
 175         /* Skip out of range objects */
 176         if (object->lod > 0) {
 177                 gdouble eye[3], obj[3];
 178                 gis_viewer_get_location(GIS_VIEWER(self), &eye[0], &eye[1], &eye[2]);
 179                 lle2xyz(eye[0], eye[1], eye[2], &eye[0], &eye[1], &eye[2]);
 180                 lle2xyz(object->center.lat, object->center.lon, object->center.elev,
 181                         &obj[0], &obj[1], &obj[2]);
 182                 gdouble dist = distd(obj, eye);
 183                 if (object->lod < dist)
 184                         return;
 185         }
 186
 187         /* Draw */
 188         glMatrixMode(GL_PROJECTION); glPushMatrix();
 189         glMatrixMode(GL_MODELVIEW);  glPushMatrix();
 190         glPushAttrib(GL_ALL_ATTRIB_BITS);
 191         switch (object->type) {
 192         case GIS_TYPE_MARKER:
 193                 _draw_marker(self, GIS_MARKER(object));
 194                 break;
 195         case GIS_TYPE_CALLBACK:
 196                 _draw_callback(self, GIS_CALLBACK(object));
 197                 break;
 198         default:
 199                 break;
 200         }
 201         glPopAttrib();
 202         glMatrixMode(GL_PROJECTION); glPopMatrix();
 203         glMatrixMode(GL_MODELVIEW);  glPopMatrix();
 204 }
 205
 206 static void _load_object(GisOpenGL *self, GisObject *object)
 207 {
 208         g_debug("GisOpenGL: load_object");
 209         switch (object->type) {
 210         case GIS_TYPE_MARKER: {
 211                 GisMarker *marker = GIS_MARKER(object);
 212                 cairo_surface_t *surface = cairo_get_target(marker->cairo);
 213                 gdouble width  = cairo_image_surface_get_width(surface);
 214                 gdouble height = cairo_image_surface_get_height(surface);
 215
 216                 _gis_opengl_begin(self);
 217                 glEnable(GL_TEXTURE_2D);
 218                 glGenTextures(1, &marker->tex);
 219                 glBindTexture(GL_TEXTURE_2D, marker->tex);
 220
 221                 glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
 222                 glPixelStorei(GL_PACK_ALIGNMENT, 1);
 223                 glTexImage2D(GL_TEXTURE_2D, 0, 4, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE,
 224                                 cairo_image_surface_get_data(surface));
 225                 glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 226                 glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 227                 g_debug("load_texture: %d", marker->tex);
 228                 _gis_opengl_end(self);
 229                 break;
 230         }
 231         default:
 232                 break;
 233         }
 234 }
 235
 236 static void _unload_object(GisOpenGL *self, GisObject *object)
 237 {
 238         g_debug("GisOpenGL: unload_object");
 239         switch (object->type) {
 240         case GIS_TYPE_MARKER: {
 241                 GisMarker *marker = GIS_MARKER(object);
 242                 g_debug("delete_texture: %d", marker->tex);
 243                 glDeleteTextures(1, &marker->tex);
 244                 break;
 245         }
 246         default:
 247                 break;
 248         }
 249 }
 250
 251
 252 /*************
 253  * Callbacks *
 254  *************/
 255 /* The unsorted/sroted GLists are blank head nodes,
 256  * This way us we can remove objects from the level just by fixing up links
 257  * I.e. we don't need to do a lookup to remove an object if we have its GList */
 258 struct RenderLevel {
 259         GList unsorted;
 260         GList sorted;
 261 };
 262
 263 static void on_realize(GisOpenGL *self, gpointer _)
 264 {
 265         g_debug("GisOpenGL: on_realize");
 266         _set_visuals(self);
 267         g_mutex_lock(self->sphere_lock);
 268         roam_sphere_update_errors(self->sphere);
 269         g_mutex_unlock(self->sphere_lock);
 270 }
 271 static gboolean on_configure(GisOpenGL *self, GdkEventConfigure *event, gpointer _)
 272 {
 273         g_debug("GisOpenGL: on_configure");
 274         _gis_opengl_begin(self);
 275
 276         double width  = GTK_WIDGET(self)->allocation.width;
 277         double height = GTK_WIDGET(self)->allocation.height;
 278
 279         /* Setup OpenGL Window */
 280         glViewport(0, 0, width, height);
 281         glMatrixMode(GL_PROJECTION);
 282         glLoadIdentity();
 283         double ang = atan(height/FOV_DIST);
 284         gluPerspective(rad2deg(ang)*2, width/height, 1, 10*EARTH_R);
 285
 286 #ifndef ROAM_DEBUG
 287         g_mutex_lock(self->sphere_lock);
 288         roam_sphere_update_errors(self->sphere);
 289         g_mutex_unlock(self->sphere_lock);
 290 #endif
 291
 292         _gis_opengl_end(self);
 293         return FALSE;
 294 }
 295
 296 static gboolean _draw_level(gpointer key, gpointer value, gpointer user_data)
 297 {
 298         g_debug("GisOpenGL: _draw_level - level=%-4d", (int)key);
 299         GisOpenGL *self = user_data;
 300         struct RenderLevel *level = value;
 301         int nsorted = 0, nunsorted = 0;
 302         GList *cur = NULL;
 303
 304         /* Draw opaque objects without sorting */
 305         glDepthMask(TRUE);
 306         glClear(GL_DEPTH_BUFFER_BIT);
 307         for (cur = level->unsorted.next; cur; cur = cur->next, nunsorted++)
 308                 _draw_object(self, GIS_OBJECT(cur->data));
 309
 310         /* Freeze depth buffer and draw transparent objects sorted */
 311         /* TODO: sorting */
 312         //glDepthMask(FALSE);
 313         glAlphaFunc(GL_GREATER, 0.1);
 314         for (cur = level->sorted.next; cur; cur = cur->next, nsorted++)
 315                 _draw_object(self, GIS_OBJECT(cur->data));
 316
 317         /* TODO: Prune empty levels */
 318
 319         g_debug("GisOpenGL: _draw_level - drew %d,%d objects",
 320                         nunsorted, nsorted);
 321         return FALSE;
 322 }
 323
 324 static gboolean on_expose(GisOpenGL *self, GdkEventExpose *event, gpointer _)
 325 {
 326         g_debug("GisOpenGL: on_expose - begin");
 327         _gis_opengl_begin(self);
 328
 329         glClear(GL_COLOR_BUFFER_BIT);
 330
 331         _set_visuals(self);
 332 #ifdef ROAM_DEBUG
 333         glColor4f(0.0, 0.0, 9.0, 0.6);
 334         glDisable(GL_TEXTURE_2D);
 335         glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
 336         roam_sphere_draw(self->sphere);
 337         //roam_sphere_draw_normals(self->sphere);
 338 #else
 339         g_tree_foreach(self->objects, _draw_level, self);
 340         if (self->wireframe) {
 341                 glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
 342                 roam_sphere_draw(self->sphere);
 343         }
 344 #endif
 345
 346         GdkGLDrawable *gldrawable = gtk_widget_get_gl_drawable(GTK_WIDGET(self));
 347         gdk_gl_drawable_swap_buffers(gldrawable);
 348
 349         _gis_opengl_end(self);
 350         g_debug("GisOpenGL: on_expose - end\n");
 351         return FALSE;
 352 }
 353
 354 static gboolean on_key_press(GisOpenGL *self, GdkEventKey *event, gpointer _)
 355 {
 356         g_debug("GisOpenGL: on_key_press - key=%x, state=%x, plus=%x",
 357                         event->keyval, event->state, GDK_plus);
 358
 359         guint kv = event->keyval;
 360         gdk_threads_leave();
 361         /* Testing */
 362         if (kv == GDK_w) {
 363                 self->wireframe = !self->wireframe;
 364                 gtk_widget_queue_draw(GTK_WIDGET(self));
 365         }
 366 #ifdef ROAM_DEBUG
 367         else if (kv == GDK_n) roam_sphere_split_one(self->sphere);
 368         else if (kv == GDK_p) roam_sphere_merge_one(self->sphere);
 369         else if (kv == GDK_r) roam_sphere_split_merge(self->sphere);
 370         else if (kv == GDK_u) roam_sphere_update_errors(self->sphere);
 371         gdk_threads_enter();
 372         gtk_widget_queue_draw(GTK_WIDGET(self));
 373 #else
 374         gdk_threads_enter();
 375 #endif
 376         return FALSE;
 377 }
 378
 379 static gboolean _update_errors_cb(gpointer sphere)
 380 {
 381         roam_sphere_update_errors(sphere);
 382         return FALSE;
 383 }
 384 static void on_view_changed(GisOpenGL *self,
 385                 gdouble _1, gdouble _2, gdouble _3)
 386 {
 387         g_debug("GisOpenGL: on_view_changed");
 388         gdk_threads_enter();
 389         _gis_opengl_begin(self);
 390         _set_visuals(self);
 391 #ifndef ROAM_DEBUG
 392         g_idle_add_full(G_PRIORITY_HIGH_IDLE+30, _update_errors_cb, self->sphere, NULL);
 393         //roam_sphere_update_errors(self->sphere);
 394 #endif
 395         _gis_opengl_end(self);
 396         gdk_threads_leave();
 397 }
 398
 399 static gboolean on_idle(GisOpenGL *self)
 400 {
 401         //g_debug("GisOpenGL: on_idle");
 402         gdk_threads_enter();
 403         _gis_opengl_begin(self);
 404         g_mutex_lock(self->sphere_lock);
 405         if (roam_sphere_split_merge(self->sphere))
 406                 gtk_widget_queue_draw(GTK_WIDGET(self));
 407         g_mutex_unlock(self->sphere_lock);
 408         _gis_opengl_end(self);
 409         gdk_threads_leave();
 410         return TRUE;
 411 }
 412
 413
 414 /*********************
 415  * GisViewer methods *
 416  *********************/
 417 GisViewer *gis_opengl_new(GisPlugins *plugins, GisPrefs *prefs)
 418 {
 419         g_debug("GisOpenGL: new");
 420         GisViewer *self = g_object_new(GIS_TYPE_OPENGL, NULL);
 421         gis_viewer_setup(self, plugins, prefs);
 422         return self;
 423 }
 424
 425 static void gis_opengl_center_position(GisViewer *_self, gdouble lat, gdouble lon, gdouble elev)
 426 {
 427         GisOpenGL *self = GIS_OPENGL(_self);
 428         glRotatef(lon, 0, 1, 0);
 429         glRotatef(-lat, 1, 0, 0);
 430         glTranslatef(0, 0, elev2rad(elev));
 431 }
 432
 433 static void gis_opengl_project(GisViewer *_self,
 434                 gdouble lat, gdouble lon, gdouble elev,
 435                 gdouble *px, gdouble *py, gdouble *pz)
 436 {
 437         GisOpenGL *self = GIS_OPENGL(_self);
 438         gdouble x, y, z;
 439         lle2xyz(lat, lon, elev, &x, &y, &z);
 440         gluProject(x, y, z,
 441                 self->sphere->view->model,
 442                 self->sphere->view->proj,
 443                 self->sphere->view->view,
 444                 px, py, pz);
 445 }
 446
 447 static void gis_opengl_render_tile(GisViewer *_self, GisTile *tile)
 448 {
 449         GisOpenGL *self = GIS_OPENGL(_self);
 450         if (!tile || !tile->data)
 451                 return;
 452         GList *triangles = roam_sphere_get_intersect(self->sphere, FALSE,
 453                         tile->edge.n, tile->edge.s, tile->edge.e, tile->edge.w);
 454         if (!triangles)
 455                 g_warning("GisOpenGL: render_tiles - No triangles to draw: edges=%f,%f,%f,%f",
 456                         tile->edge.n, tile->edge.s, tile->edge.e, tile->edge.w);
 457         //g_message("rendering %4d triangles for tile edges=%7.2f,%7.2f,%7.2f,%7.2f",
 458         //              g_list_length(triangles), tile->edge.n, tile->edge.s, tile->edge.e, tile->edge.w);
 459         for (GList *cur = triangles; cur; cur = cur->next) {
 460                 RoamTriangle *tri = cur->data;
 461
 462                 gdouble lat[3] = {tri->p.r->lat, tri->p.m->lat, tri->p.l->lat};
 463                 gdouble lon[3] = {tri->p.r->lon, tri->p.m->lon, tri->p.l->lon};
 464
 465                 if (lon[0] < -90 || lon[1] < -90 || lon[2] < -90) {
 466                         if (lon[0] > 90) lon[0] -= 360;
 467                         if (lon[1] > 90) lon[1] -= 360;
 468                         if (lon[2] > 90) lon[2] -= 360;
 469                 }
 470
 471                 gdouble n = tile->edge.n;
 472                 gdouble s = tile->edge.s;
 473                 gdouble e = tile->edge.e;
 474                 gdouble w = tile->edge.w;
 475
 476                 gdouble londist = e - w;
 477                 gdouble latdist = n - s;
 478
 479                 gdouble xy[3][2] = {
 480                         {(lon[0]-w)/londist, 1-(lat[0]-s)/latdist},
 481                         {(lon[1]-w)/londist, 1-(lat[1]-s)/latdist},
 482                         {(lon[2]-w)/londist, 1-(lat[2]-s)/latdist},
 483                 };
 484
 485                 //if ((lat[0] == 90 && (xy[0][0] < 0 || xy[0][0] > 1)) ||
 486                 //    (lat[1] == 90 && (xy[1][0] < 0 || xy[1][0] > 1)) ||
 487                 //    (lat[2] == 90 && (xy[2][0] < 0 || xy[2][0] > 1)))
 488                 //      g_message("w,e=%4.f,%4.f   "
 489                 //                "lat,lon,x,y="
 490                 //                "%4.1f,%4.0f,%4.2f,%4.2f   "
 491                 //                "%4.1f,%4.0f,%4.2f,%4.2f   "
 492                 //                "%4.1f,%4.0f,%4.2f,%4.2f   ",
 493                 //              w,e,
 494                 //              lat[0], lon[0], xy[0][0], xy[0][1],
 495                 //              lat[1], lon[1], xy[1][0], xy[1][1],
 496                 //              lat[2], lon[2], xy[2][0], xy[2][1]);
 497
 498                 /* Fix poles */
 499                 if (lat[0] == 90 || lat[0] == -90) xy[0][0] = 0.5;
 500                 if (lat[1] == 90 || lat[1] == -90) xy[1][0] = 0.5;
 501                 if (lat[2] == 90 || lat[2] == -90) xy[2][0] = 0.5;
 502
 503                 glEnable(GL_TEXTURE_2D);
 504                 glBindTexture(GL_TEXTURE_2D, *(guint*)tile->data);
 505                 glBegin(GL_TRIANGLES);
 506                 glNormal3dv(tri->p.r->norm); glTexCoord2dv(xy[0]); glVertex3dv((double*)tri->p.r);
 507                 glNormal3dv(tri->p.m->norm); glTexCoord2dv(xy[1]); glVertex3dv((double*)tri->p.m);
 508                 glNormal3dv(tri->p.l->norm); glTexCoord2dv(xy[2]); glVertex3dv((double*)tri->p.l);
 509                 glEnd();
 510         }
 511         g_list_free(triangles);
 512 }
 513
 514 static void gis_opengl_render_tiles(GisViewer *_self, GisTile *tile)
 515 {
 516         GisOpenGL *self = GIS_OPENGL(_self);
 517         /* Only render children if possible */
 518         gboolean has_children = TRUE;
 519         GisTile *child;
 520         gis_tile_foreach(tile, child)
 521                 if (!child || !child->data)
 522                         has_children = FALSE;
 523         if (has_children)
 524                 /* Only render children */
 525                 gis_tile_foreach(tile, child)
 526                         gis_opengl_render_tiles(_self, child);
 527         else
 528                 /* No children, render this tile */
 529                 gis_opengl_render_tile(_self, tile);
 530 }
 531
 532 static void gis_opengl_set_height_func(GisViewer *_self, GisTile *tile,
 533                 RoamHeightFunc height_func, gpointer user_data, gboolean update)
 534 {
 535         GisOpenGL *self = GIS_OPENGL(_self);
 536         if (!tile)
 537                 return;
 538         /* TODO: get points? */
 539         g_mutex_lock(self->sphere_lock);
 540         GList *triangles = roam_sphere_get_intersect(self->sphere, TRUE,
 541                         tile->edge.n, tile->edge.s, tile->edge.e, tile->edge.w);
 542         for (GList *cur = triangles; cur; cur = cur->next) {
 543                 RoamTriangle *tri = cur->data;
 544                 RoamPoint *points[] = {tri->p.l, tri->p.m, tri->p.r, tri->split};
 545                 for (int i = 0; i < G_N_ELEMENTS(points); i++) {
 546                         if (tile->edge.n >= points[i]->lat && points[i]->lat >= tile->edge.s &&
 547                             tile->edge.e >= points[i]->lon && points[i]->lon >= tile->edge.w) {
 548                                 points[i]->height_func = height_func;
 549                                 points[i]->height_data = user_data;
 550                                 roam_point_update_height(points[i]);
 551                         }
 552                 }
 553         }
 554         g_list_free(triangles);
 555         g_mutex_unlock(self->sphere_lock);
 556 }
 557
 558 static void _gis_opengl_clear_height_func_rec(RoamTriangle *root)
 559 {
 560         if (!root)
 561                 return;
 562         RoamPoint *points[] = {root->p.l, root->p.m, root->p.r, root->split};
 563         for (int i = 0; i < G_N_ELEMENTS(points); i++) {
 564                 points[i]->height_func = NULL;
 565                 points[i]->height_data = NULL;
 566                 roam_point_update_height(points[i]);
 567         }
 568         _gis_opengl_clear_height_func_rec(root->kids[0]);
 569         _gis_opengl_clear_height_func_rec(root->kids[1]);
 570 }
 571
 572 static void gis_opengl_clear_height_func(GisViewer *_self)
 573 {
 574         GisOpenGL *self = GIS_OPENGL(_self);
 575         for (int i = 0; i < G_N_ELEMENTS(self->sphere->roots); i++)
 576                 _gis_opengl_clear_height_func_rec(self->sphere->roots[i]);
 577 }
 578
 579 static void gis_opengl_begin(GisViewer *_self)
 580 {
 581         g_assert(GIS_IS_OPENGL(_self));
 582         _gis_opengl_begin(GIS_OPENGL(_self));
 583 }
 584
 585 static void gis_opengl_end(GisViewer *_self)
 586 {
 587         g_assert(GIS_IS_OPENGL(_self));
 588         _gis_opengl_end(GIS_OPENGL(_self));
 589 }
 590
 591 static gpointer gis_opengl_add(GisViewer *_self, GisObject *object,
 592                 gint key, gboolean sort)
 593 {
 594         g_assert(GIS_IS_OPENGL(_self));
 595         GisOpenGL *self = GIS_OPENGL(_self);
 596         _load_object(self, object);
 597         struct RenderLevel *level = g_tree_lookup(self->objects, (gpointer)key);
 598         if (!level) {
 599                 level = g_new0(struct RenderLevel, 1);
 600                 g_tree_insert(self->objects, (gpointer)key, level);
 601         }
 602         GList *list = sort ? &level->sorted : &level->unsorted;
 603         list->next = g_list_prepend(list->next, object);
 604         return list->next;
 605 }
 606
 607 static void gis_opengl_remove(GisViewer *_self, gpointer _link)
 608 {
 609         g_assert(GIS_IS_OPENGL(_self));
 610         GList *link = _link;
 611         GisOpenGL *self = GIS_OPENGL(_self);
 612         _unload_object(self, link->data);
 613         /* Just unlink and free it (blowup link to avoid warnings) */
 614         link = g_list_delete_link(NULL, link);
 615 }
 616
 617 /****************
 618  * GObject code *
 619  ****************/
 620 static int _objects_cmp(gconstpointer _a, gconstpointer _b)
 621 {
 622         gint a = (int)_a, b = (int)_b;
 623         return a < b ? -1 :
 624                a > b ?  1 : 0;
 625 }
 626
 627 G_DEFINE_TYPE(GisOpenGL, gis_opengl, GIS_TYPE_VIEWER);
 628 static void gis_opengl_init(GisOpenGL *self)
 629 {
 630         g_debug("GisOpenGL: init");
 631         /* OpenGL setup */
 632         GdkGLConfig *glconfig = gdk_gl_config_new_by_mode(
 633                         GDK_GL_MODE_RGBA   | GDK_GL_MODE_DEPTH |
 634                         GDK_GL_MODE_DOUBLE | GDK_GL_MODE_ALPHA);
 635         if (!glconfig)
 636                 g_error("Failed to create glconfig");
 637         if (!gtk_widget_set_gl_capability(GTK_WIDGET(self),
 638                                 glconfig, NULL, TRUE, GDK_GL_RGBA_TYPE))
 639                 g_error("GL lacks required capabilities");
 640         g_object_unref(glconfig);
 641
 642         gtk_widget_set_size_request(GTK_WIDGET(self), 600, 550);
 643         gtk_widget_set_events(GTK_WIDGET(self),
 644                         GDK_BUTTON_PRESS_MASK |
 645                         GDK_ENTER_NOTIFY_MASK |
 646                         GDK_KEY_PRESS_MASK);
 647         g_object_set(self, "can-focus", TRUE, NULL);
 648
 649         self->objects = g_tree_new(_objects_cmp);
 650         self->sphere = roam_sphere_new(self);
 651         self->sphere_lock = g_mutex_new();
 652
 653 #ifndef ROAM_DEBUG
 654         self->sm_source[0] = g_timeout_add_full(G_PRIORITY_HIGH_IDLE+30, 33,  (GSourceFunc)on_idle, self, NULL);
 655         self->sm_source[1] = g_timeout_add_full(G_PRIORITY_HIGH_IDLE+10, 500, (GSourceFunc)on_idle, self, NULL);
 656 #endif
 657
 658         g_signal_connect(self, "realize",          G_CALLBACK(on_realize),      NULL);
 659         g_signal_connect(self, "configure-event",  G_CALLBACK(on_configure),    NULL);
 660         g_signal_connect(self, "expose-event",     G_CALLBACK(on_expose),       NULL);
 661
 662         g_signal_connect(self, "key-press-event",  G_CALLBACK(on_key_press),    NULL);
 663
 664         g_signal_connect(self, "location-changed", G_CALLBACK(on_view_changed), NULL);
 665         g_signal_connect(self, "rotation-changed", G_CALLBACK(on_view_changed), NULL);
 666 }
 667 static void gis_opengl_dispose(GObject *_self)
 668 {
 669         g_debug("GisOpenGL: dispose");
 670         GisOpenGL *self = GIS_OPENGL(_self);
 671         if (self->sm_source[0]) {
 672                 g_source_remove(self->sm_source[0]);
 673                 self->sm_source[0] = 0;
 674         }
 675         if (self->sm_source[1]) {
 676                 g_source_remove(self->sm_source[1]);
 677                 self->sm_source[1] = 0;
 678         }
 679         /* TODO: Cleanup/free objects tree */
 680         G_OBJECT_CLASS(gis_opengl_parent_class)->dispose(_self);
 681 }
 682 static void gis_opengl_finalize(GObject *_self)
 683 {
 684         g_debug("GisViewer: finalize");
 685         GisOpenGL *self = GIS_OPENGL(_self);
 686         roam_sphere_free(self->sphere);
 687         g_mutex_free(self->sphere_lock);
 688         G_OBJECT_CLASS(gis_opengl_parent_class)->finalize(_self);
 689 }
 690 static void gis_opengl_class_init(GisOpenGLClass *klass)
 691 {
 692         g_debug("GisOpenGL: class_init");
 693         GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
 694         gobject_class->dispose = gis_opengl_dispose;
 695
 696         GisViewerClass *viewer_class = GIS_VIEWER_CLASS(klass);
 697         viewer_class->center_position   = gis_opengl_center_position;
 698         viewer_class->project           = gis_opengl_project;
 699         viewer_class->clear_height_func = gis_opengl_clear_height_func;
 700         viewer_class->set_height_func   = gis_opengl_set_height_func;
 701         viewer_class->render_tile       = gis_opengl_render_tile;
 702         viewer_class->render_tiles      = gis_opengl_render_tiles;
 703         viewer_class->begin             = gis_opengl_begin;
 704         viewer_class->end               = gis_opengl_end;
 705         viewer_class->add               = gis_opengl_add;
 706         viewer_class->remove            = gis_opengl_remove;
 707 }