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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, GList *triangles)
126 {
127         if (!tile || !tile->data)
128                 return;
129         if (!triangles)
130                 g_warning("GisOpenGL: _draw_tiles - No triangles to draw: edges=%f,%f,%f,%f",
131                         tile->edge.n, tile->edge.s, tile->edge.e, tile->edge.w);
132         //g_message("drawing %4d triangles for tile edges=%7.2f,%7.2f,%7.2f,%7.2f",
133         //              g_list_length(triangles), tile->edge.n, tile->edge.s, tile->edge.e, tile->edge.w);
134         for (GList *cur = triangles; cur; cur = cur->next) {
135                 RoamTriangle *tri = cur->data;
136
137                 gdouble lat[3] = {tri->p.r->lat, tri->p.m->lat, tri->p.l->lat};
138                 gdouble lon[3] = {tri->p.r->lon, tri->p.m->lon, tri->p.l->lon};
139
140                 if (lon[0] < -90 || lon[1] < -90 || lon[2] < -90) {
141                         if (lon[0] > 90) lon[0] -= 360;
142                         if (lon[1] > 90) lon[1] -= 360;
143                         if (lon[2] > 90) lon[2] -= 360;
144                 }
145
146                 gdouble n = tile->edge.n;
147                 gdouble s = tile->edge.s;
148                 gdouble e = tile->edge.e;
149                 gdouble w = tile->edge.w;
150
151                 gdouble londist = e - w;
152                 gdouble latdist = n - s;
153
154                 gdouble xy[3][2] = {
155                         {(lon[0]-w)/londist, 1-(lat[0]-s)/latdist},
156                         {(lon[1]-w)/londist, 1-(lat[1]-s)/latdist},
157                         {(lon[2]-w)/londist, 1-(lat[2]-s)/latdist},
158                 };
159
160                 //if ((lat[0] == 90 && (xy[0][0] < 0 || xy[0][0] > 1)) ||
161                 //    (lat[1] == 90 && (xy[1][0] < 0 || xy[1][0] > 1)) ||
162                 //    (lat[2] == 90 && (xy[2][0] < 0 || xy[2][0] > 1)))
163                 //      g_message("w,e=%4.f,%4.f   "
164                 //                "lat,lon,x,y="
165                 //                "%4.1f,%4.0f,%4.2f,%4.2f   "
166                 //                "%4.1f,%4.0f,%4.2f,%4.2f   "
167                 //                "%4.1f,%4.0f,%4.2f,%4.2f   ",
168                 //              w,e,
169                 //              lat[0], lon[0], xy[0][0], xy[0][1],
170                 //              lat[1], lon[1], xy[1][0], xy[1][1],
171                 //              lat[2], lon[2], xy[2][0], xy[2][1]);
172
173                 /* Fix poles */
174                 if (lat[0] == 90 || lat[0] == -90) xy[0][0] = 0.5;
175                 if (lat[1] == 90 || lat[1] == -90) xy[1][0] = 0.5;
176                 if (lat[2] == 90 || lat[2] == -90) xy[2][0] = 0.5;
177
178                 glEnable(GL_TEXTURE_2D);
179                 glBindTexture(GL_TEXTURE_2D, *(guint*)tile->data);
180                 glBegin(GL_TRIANGLES);
181                 glNormal3dv(tri->p.r->norm); glTexCoord2dv(xy[0]); glVertex3dv((double*)tri->p.r);
182                 glNormal3dv(tri->p.m->norm); glTexCoord2dv(xy[1]); glVertex3dv((double*)tri->p.m);
183                 glNormal3dv(tri->p.l->norm); glTexCoord2dv(xy[2]); glVertex3dv((double*)tri->p.l);
184                 glEnd();
185         }
186         g_list_free(triangles);
187 }
188
189 static void _draw_tiles(GisOpenGL *opengl, GisTile *tile)
190 {
191         /* Only draw children if possible */
192         gboolean has_children = FALSE;
193         GisTile *child;
194         gis_tile_foreach(tile, child)
195                 if (child && child->data)
196                         has_children = TRUE;
197
198         GList *triangles = NULL;
199         if (has_children) {
200                 /* TODO: simplify this */
201                 const gdouble rows = G_N_ELEMENTS(tile->children);
202                 const gdouble cols = G_N_ELEMENTS(tile->children[0]);
203                 const gdouble lat_dist = tile->edge.n - tile->edge.s;
204                 const gdouble lon_dist = tile->edge.e - tile->edge.w;
205                 const gdouble lat_step = lat_dist / rows;
206                 const gdouble lon_step = lon_dist / cols;
207                 int row, col;
208                 gis_tile_foreach_index(tile, row, col) {
209                         GisTile *child = tile->children[row][col];
210                         if (child && child->data) {
211                                 _draw_tiles(opengl, child);
212                         } else {
213                                 const gdouble n = tile->edge.n-(lat_step*(row+0));
214                                 const gdouble s = tile->edge.n-(lat_step*(row+1));
215                                 const gdouble e = tile->edge.w+(lon_step*(col+1));
216                                 const gdouble w = tile->edge.w+(lon_step*(col+0));
217                                 GList *these = roam_sphere_get_intersect(opengl->sphere, FALSE, n, s, e, w);
218                                 triangles = g_list_concat(triangles, these);
219                         }
220                 }
221         } else {
222                 triangles = roam_sphere_get_intersect(opengl->sphere, FALSE,
223                                 tile->edge.n, tile->edge.s, tile->edge.e, tile->edge.w);
224         }
225         if (triangles)
226                 _draw_tile(opengl, tile, triangles);
227 }
228
229 static void _draw_marker(GisOpenGL *opengl, GisMarker *marker)
230 {
231         GisPoint *point = gis_object_center(marker);
232         gdouble px, py, pz;
233         gis_viewer_project(GIS_VIEWER(opengl),
234                         point->lat, point->lon, point->elev,
235                         &px, &py, &pz);
236         gint win_width  = GTK_WIDGET(opengl)->allocation.width;
237         gint win_height = GTK_WIDGET(opengl)->allocation.height;
238         py = win_height - py;
239         if (pz > 1)
240                 return;
241
242         //g_debug("GisOpenGL: draw_marker - %s pz=%f ", marker->label, pz);
243
244         cairo_surface_t *surface = cairo_get_target(marker->cairo);
245         gdouble width  = cairo_image_surface_get_width(surface);
246         gdouble height = cairo_image_surface_get_height(surface);
247
248         glMatrixMode(GL_PROJECTION); glLoadIdentity();
249         glMatrixMode(GL_MODELVIEW);  glLoadIdentity();
250         glOrtho(0, win_width, win_height, 0, -1, 1);
251         glTranslated(px - marker->xoff,
252                      py - marker->yoff, 0);
253
254         glDisable(GL_LIGHTING);
255         glDisable(GL_COLOR_MATERIAL);
256         glDisable(GL_DEPTH_TEST);
257         glEnable(GL_TEXTURE_2D);
258         glBindTexture(GL_TEXTURE_2D, marker->tex);
259         glDisable(GL_CULL_FACE);
260         glBegin(GL_QUADS);
261         glTexCoord2f(1, 0); glVertex3f(width, 0     , 0);
262         glTexCoord2f(1, 1); glVertex3f(width, height, 0);
263         glTexCoord2f(0, 1); glVertex3f(0    , height, 0);
264         glTexCoord2f(0, 0); glVertex3f(0    , 0     , 0);
265         glEnd();
266 }
267
268 static void _draw_callback(GisOpenGL *opengl, GisCallback *callback)
269 {
270         callback->callback(callback, callback->user_data);
271 }
272
273 static void _draw_object(GisOpenGL *opengl, GisObject *object)
274 {
275         //g_debug("GisOpenGL: draw_object");
276         /* Skip out of range objects */
277         if (object->lod > 0) {
278                 gdouble eye[3], obj[3];
279                 gis_viewer_get_location(GIS_VIEWER(opengl), &eye[0], &eye[1], &eye[2]);
280                 lle2xyz(eye[0], eye[1], eye[2], &eye[0], &eye[1], &eye[2]);
281                 lle2xyz(object->center.lat, object->center.lon, object->center.elev,
282                         &obj[0], &obj[1], &obj[2]);
283                 gdouble dist = distd(obj, eye);
284                 if (object->lod < dist)
285                         return;
286         }
287
288         /* Draw */
289         glMatrixMode(GL_PROJECTION); glPushMatrix();
290         glMatrixMode(GL_MODELVIEW);  glPushMatrix();
291         glPushAttrib(GL_ALL_ATTRIB_BITS);
292         if (GIS_IS_MARKER(object)) {
293                 _draw_marker(opengl, GIS_MARKER(object));
294         } else if (GIS_IS_CALLBACK(object)) {
295                 _draw_callback(opengl, GIS_CALLBACK(object));
296         } else if (GIS_IS_TILE(object)) {
297                 glEnable(GL_DEPTH_TEST);
298                 glDepthFunc(GL_LESS);
299                 _draw_tiles(opengl, GIS_TILE(object));
300         }
301         glPopAttrib();
302         glMatrixMode(GL_PROJECTION); glPopMatrix();
303         glMatrixMode(GL_MODELVIEW);  glPopMatrix();
304 }
305
306 static void _load_object(GisOpenGL *opengl, GisObject *object)
307 {
308         g_debug("GisOpenGL: load_object");
309         if (GIS_IS_MARKER(object)) {
310                 GisMarker *marker = GIS_MARKER(object);
311                 cairo_surface_t *surface = cairo_get_target(marker->cairo);
312                 gdouble width  = cairo_image_surface_get_width(surface);
313                 gdouble height = cairo_image_surface_get_height(surface);
314
315                 glEnable(GL_TEXTURE_2D);
316                 glGenTextures(1, &marker->tex);
317                 glBindTexture(GL_TEXTURE_2D, marker->tex);
318
319                 glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
320                 glPixelStorei(GL_PACK_ALIGNMENT, 1);
321                 glTexImage2D(GL_TEXTURE_2D, 0, 4, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE,
322                                 cairo_image_surface_get_data(surface));
323                 glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
324                 glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
325                 g_debug("load_texture: %d", marker->tex);
326         }
327 }
328
329 static void _unload_object(GisOpenGL *opengl, GisObject *object)
330 {
331         g_debug("GisOpenGL: unload_object");
332         if (GIS_IS_MARKER(object)) {
333                 GisMarker *marker = GIS_MARKER(object);
334                 glDeleteTextures(1, &marker->tex);
335         }
336 }
337
338
339 /*************
340  * Callbacks *
341  *************/
342 /* The unsorted/sroted GLists are blank head nodes,
343  * This way us we can remove objects from the level just by fixing up links
344  * I.e. we don't need to do a lookup to remove an object if we have its GList */
345 struct RenderLevel {
346         GList unsorted;
347         GList sorted;
348 };
349
350 static gboolean on_configure(GisOpenGL *opengl, GdkEventConfigure *event, gpointer _)
351 {
352         g_debug("GisOpenGL: on_configure");
353
354         double width  = GTK_WIDGET(opengl)->allocation.width;
355         double height = GTK_WIDGET(opengl)->allocation.height;
356
357         /* Setup OpenGL Window */
358         glViewport(0, 0, width, height);
359         glMatrixMode(GL_PROJECTION);
360         glLoadIdentity();
361         double ang = atan(height/FOV_DIST);
362         gluPerspective(rad2deg(ang)*2, width/height, 1, 10*EARTH_R);
363
364 #ifndef ROAM_DEBUG
365         g_mutex_lock(opengl->sphere_lock);
366         roam_sphere_update_errors(opengl->sphere);
367         g_mutex_unlock(opengl->sphere_lock);
368 #endif
369
370         return FALSE;
371 }
372
373 static void on_realize(GisOpenGL *opengl, gpointer _)
374 {
375         g_debug("GisOpenGL: on_realize");
376
377         GdkGLContext   *glcontext  = gtk_widget_get_gl_context(GTK_WIDGET(opengl));
378         GdkGLDrawable  *gldrawable = gtk_widget_get_gl_drawable(GTK_WIDGET(opengl));
379         if (!gdk_gl_drawable_gl_begin(gldrawable, glcontext))
380                 g_assert_not_reached();
381
382         _set_visuals(opengl);
383         on_configure(opengl, NULL, NULL);
384 }
385
386 static gboolean _draw_level(gpointer key, gpointer value, gpointer user_data)
387 {
388         g_debug("GisOpenGL: _draw_level - level=%-4d", (int)key);
389         GisOpenGL *opengl = user_data;
390         struct RenderLevel *level = value;
391         int nsorted = 0, nunsorted = 0;
392         GList *cur = NULL;
393
394         /* Draw opaque objects without sorting */
395         glDepthMask(TRUE);
396         glClear(GL_DEPTH_BUFFER_BIT);
397         for (cur = level->unsorted.next; cur; cur = cur->next, nunsorted++)
398                 _draw_object(opengl, GIS_OBJECT(cur->data));
399
400         /* Freeze depth buffer and draw transparent objects sorted */
401         /* TODO: sorting */
402         //glDepthMask(FALSE);
403         glAlphaFunc(GL_GREATER, 0.1);
404         for (cur = level->sorted.next; cur; cur = cur->next, nsorted++)
405                 _draw_object(opengl, GIS_OBJECT(cur->data));
406
407         /* TODO: Prune empty levels */
408
409         g_debug("GisOpenGL: _draw_level - drew %d,%d objects",
410                         nunsorted, nsorted);
411         return FALSE;
412 }
413
414 static gboolean on_expose(GisOpenGL *opengl, GdkEventExpose *event, gpointer _)
415 {
416         g_debug("GisOpenGL: on_expose - begin");
417
418         glClear(GL_COLOR_BUFFER_BIT);
419
420         _set_visuals(opengl);
421 #ifdef ROAM_DEBUG
422         glColor4f(0.0, 0.0, 9.0, 0.6);
423         glDisable(GL_TEXTURE_2D);
424         glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
425         roam_sphere_draw(opengl->sphere);
426         //roam_sphere_draw_normals(opengl->sphere);
427 #else
428         g_tree_foreach(opengl->objects, _draw_level, opengl);
429         if (opengl->wireframe) {
430                 glClear(GL_DEPTH_BUFFER_BIT);
431                 glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
432                 roam_sphere_draw(opengl->sphere);
433         }
434 #endif
435
436         GdkGLDrawable *gldrawable = gtk_widget_get_gl_drawable(GTK_WIDGET(opengl));
437         gdk_gl_drawable_swap_buffers(gldrawable);
438
439         g_debug("GisOpenGL: on_expose - end\n");
440         return FALSE;
441 }
442
443 static gboolean on_key_press(GisOpenGL *opengl, GdkEventKey *event, gpointer _)
444 {
445         g_debug("GisOpenGL: on_key_press - key=%x, state=%x, plus=%x",
446                         event->keyval, event->state, GDK_plus);
447
448         guint kv = event->keyval;
449         gdk_threads_leave();
450         /* Testing */
451         if (kv == GDK_w) {
452                 opengl->wireframe = !opengl->wireframe;
453                 gtk_widget_queue_draw(GTK_WIDGET(opengl));
454         }
455 #ifdef ROAM_DEBUG
456         else if (kv == GDK_n) roam_sphere_split_one(opengl->sphere);
457         else if (kv == GDK_p) roam_sphere_merge_one(opengl->sphere);
458         else if (kv == GDK_r) roam_sphere_split_merge(opengl->sphere);
459         else if (kv == GDK_u) roam_sphere_update_errors(opengl->sphere);
460         gdk_threads_enter();
461         gtk_widget_queue_draw(GTK_WIDGET(opengl));
462 #else
463         gdk_threads_enter();
464 #endif
465         return FALSE;
466 }
467
468 static gboolean _update_errors_cb(gpointer _opengl)
469 {
470         GisOpenGL *opengl = _opengl;
471         roam_sphere_update_errors(opengl->sphere);
472         opengl->ue_source = 0;
473         return FALSE;
474 }
475 static void on_view_changed(GisOpenGL *opengl,
476                 gdouble _1, gdouble _2, gdouble _3)
477 {
478         g_debug("GisOpenGL: on_view_changed");
479         _set_visuals(opengl);
480 #ifndef ROAM_DEBUG
481         if (!opengl->ue_source)
482                 opengl->ue_source = g_idle_add_full(G_PRIORITY_HIGH_IDLE+30,
483                                 _update_errors_cb, opengl, NULL);
484         //roam_sphere_update_errors(opengl->sphere);
485 #endif
486 }
487
488 static gboolean on_idle(GisOpenGL *opengl)
489 {
490         //g_debug("GisOpenGL: on_idle");
491         gdk_threads_enter();
492         g_mutex_lock(opengl->sphere_lock);
493         if (roam_sphere_split_merge(opengl->sphere))
494                 gtk_widget_queue_draw(GTK_WIDGET(opengl));
495         g_mutex_unlock(opengl->sphere_lock);
496         gdk_threads_leave();
497         return TRUE;
498 }
499
500
501 /*********************
502  * GisViewer methods *
503  *********************/
504 /**
505  * gis_opengl_new:
506  * @plugins: the plugins store to use
507  * @prefs:   the preferences object to use
508  *
509  * Create a new OpenGL renderer.
510  *
511  * Returns: the new #GisOpenGL
512  */
513 GisViewer *gis_opengl_new(GisPlugins *plugins, GisPrefs *prefs)
514 {
515         g_debug("GisOpenGL: new");
516         GisViewer *opengl = g_object_new(GIS_TYPE_OPENGL, NULL);
517         gis_viewer_setup(opengl, plugins, prefs);
518         return opengl;
519 }
520
521 static void gis_opengl_center_position(GisViewer *_opengl, gdouble lat, gdouble lon, gdouble elev)
522 {
523         GisOpenGL *opengl = GIS_OPENGL(_opengl);
524         glRotatef(lon, 0, 1, 0);
525         glRotatef(-lat, 1, 0, 0);
526         glTranslatef(0, 0, elev2rad(elev));
527 }
528
529 static void gis_opengl_project(GisViewer *_opengl,
530                 gdouble lat, gdouble lon, gdouble elev,
531                 gdouble *px, gdouble *py, gdouble *pz)
532 {
533         GisOpenGL *opengl = GIS_OPENGL(_opengl);
534         gdouble x, y, z;
535         lle2xyz(lat, lon, elev, &x, &y, &z);
536         gluProject(x, y, z,
537                 opengl->sphere->view->model,
538                 opengl->sphere->view->proj,
539                 opengl->sphere->view->view,
540                 px, py, pz);
541 }
542
543 static void gis_opengl_set_height_func(GisViewer *_opengl, GisTile *tile,
544                 RoamHeightFunc height_func, gpointer user_data, gboolean update)
545 {
546         GisOpenGL *opengl = GIS_OPENGL(_opengl);
547         if (!tile)
548                 return;
549         /* TODO: get points? */
550         g_mutex_lock(opengl->sphere_lock);
551         GList *triangles = roam_sphere_get_intersect(opengl->sphere, TRUE,
552                         tile->edge.n, tile->edge.s, tile->edge.e, tile->edge.w);
553         for (GList *cur = triangles; cur; cur = cur->next) {
554                 RoamTriangle *tri = cur->data;
555                 RoamPoint *points[] = {tri->p.l, tri->p.m, tri->p.r, tri->split};
556                 for (int i = 0; i < G_N_ELEMENTS(points); i++) {
557                         if (tile->edge.n >= points[i]->lat && points[i]->lat >= tile->edge.s &&
558                             tile->edge.e >= points[i]->lon && points[i]->lon >= tile->edge.w) {
559                                 points[i]->height_func = height_func;
560                                 points[i]->height_data = user_data;
561                                 roam_point_update_height(points[i]);
562                         }
563                 }
564         }
565         g_list_free(triangles);
566         g_mutex_unlock(opengl->sphere_lock);
567 }
568
569 static void _gis_opengl_clear_height_func_rec(RoamTriangle *root)
570 {
571         if (!root)
572                 return;
573         RoamPoint *points[] = {root->p.l, root->p.m, root->p.r, root->split};
574         for (int i = 0; i < G_N_ELEMENTS(points); i++) {
575                 points[i]->height_func = NULL;
576                 points[i]->height_data = NULL;
577                 roam_point_update_height(points[i]);
578         }
579         _gis_opengl_clear_height_func_rec(root->kids[0]);
580         _gis_opengl_clear_height_func_rec(root->kids[1]);
581 }
582
583 static void gis_opengl_clear_height_func(GisViewer *_opengl)
584 {
585         GisOpenGL *opengl = GIS_OPENGL(_opengl);
586         for (int i = 0; i < G_N_ELEMENTS(opengl->sphere->roots); i++)
587                 _gis_opengl_clear_height_func_rec(opengl->sphere->roots[i]);
588 }
589
590 static gpointer gis_opengl_add(GisViewer *_opengl, GisObject *object,
591                 gint key, gboolean sort)
592 {
593         g_assert(GIS_IS_OPENGL(_opengl));
594         GisOpenGL *opengl = GIS_OPENGL(_opengl);
595         _load_object(opengl, object);
596         struct RenderLevel *level = g_tree_lookup(opengl->objects, (gpointer)key);
597         if (!level) {
598                 level = g_new0(struct RenderLevel, 1);
599                 g_tree_insert(opengl->objects, (gpointer)key, level);
600         }
601         GList *list = sort ? &level->sorted : &level->unsorted;
602         /* Put the link in the list */
603         GList *next = g_new0(GList, 1);
604         next->data = object;
605         next->prev = list;
606         next->next = list->next;
607         list->next = next;
608         return next;
609 }
610
611 static GisObject *gis_opengl_remove(GisViewer *_opengl, gpointer _link)
612 {
613         g_assert(GIS_IS_OPENGL(_opengl));
614         GisOpenGL *opengl = GIS_OPENGL(_opengl);
615         GList *link = _link;
616         GisObject *object = link->data;
617         _unload_object(opengl, object);
618         /* Just unlink and free it, link->prev is assured */
619         link->prev->next = link->next;
620         if (link->next)
621                 link->next->prev = link->prev;
622         g_free(link);
623         g_object_unref(object);
624         return object;
625 }
626
627 /****************
628  * GObject code *
629  ****************/
630 static int _objects_cmp(gconstpointer _a, gconstpointer _b, gpointer _)
631 {
632         gint a = (int)_a, b = (int)_b;
633         return a < b ? -1 :
634                a > b ?  1 : 0;
635 }
636 static void _objects_free(gpointer value)
637 {
638         struct RenderLevel *level = value;
639         if (level->sorted.next)
640                 g_list_free(level->sorted.next);
641         if (level->unsorted.next)
642                 g_list_free(level->unsorted.next);
643         g_free(level);
644 }
645
646 G_DEFINE_TYPE(GisOpenGL, gis_opengl, GIS_TYPE_VIEWER);
647 static void gis_opengl_init(GisOpenGL *opengl)
648 {
649         g_debug("GisOpenGL: init");
650         /* OpenGL setup */
651         GdkGLConfig *glconfig = gdk_gl_config_new_by_mode(
652                         GDK_GL_MODE_RGBA   | GDK_GL_MODE_DEPTH |
653                         GDK_GL_MODE_DOUBLE | GDK_GL_MODE_ALPHA);
654         if (!glconfig)
655                 g_error("Failed to create glconfig");
656         if (!gtk_widget_set_gl_capability(GTK_WIDGET(opengl),
657                                 glconfig, NULL, TRUE, GDK_GL_RGBA_TYPE))
658                 g_error("GL lacks required capabilities");
659         g_object_unref(glconfig);
660
661         opengl->objects = g_tree_new_full(_objects_cmp, NULL, NULL, _objects_free);
662         opengl->sphere = roam_sphere_new(opengl);
663         opengl->sphere_lock = g_mutex_new();
664
665 #ifndef ROAM_DEBUG
666         opengl->sm_source[0] = g_timeout_add_full(G_PRIORITY_HIGH_IDLE+30, 33,  (GSourceFunc)on_idle, opengl, NULL);
667         opengl->sm_source[1] = g_timeout_add_full(G_PRIORITY_HIGH_IDLE+10, 500, (GSourceFunc)on_idle, opengl, NULL);
668 #endif
669
670         gtk_widget_add_events(GTK_WIDGET(opengl), GDK_KEY_PRESS_MASK);
671         g_signal_connect(opengl, "realize",          G_CALLBACK(on_realize),      NULL);
672         g_signal_connect(opengl, "configure-event",  G_CALLBACK(on_configure),    NULL);
673         g_signal_connect(opengl, "expose-event",     G_CALLBACK(on_expose),       NULL);
674
675         g_signal_connect(opengl, "key-press-event",  G_CALLBACK(on_key_press),    NULL);
676
677         g_signal_connect(opengl, "location-changed", G_CALLBACK(on_view_changed), NULL);
678         g_signal_connect(opengl, "rotation-changed", G_CALLBACK(on_view_changed), NULL);
679 }
680 static void gis_opengl_dispose(GObject *_opengl)
681 {
682         g_debug("GisOpenGL: dispose");
683         GisOpenGL *opengl = GIS_OPENGL(_opengl);
684         if (opengl->sm_source[0]) {
685                 g_source_remove(opengl->sm_source[0]);
686                 opengl->sm_source[0] = 0;
687         }
688         if (opengl->sm_source[1]) {
689                 g_source_remove(opengl->sm_source[1]);
690                 opengl->sm_source[1] = 0;
691         }
692         if (opengl->ue_source) {
693                 g_source_remove(opengl->ue_source);
694                 opengl->ue_source = 0;
695         }
696         G_OBJECT_CLASS(gis_opengl_parent_class)->dispose(_opengl);
697 }
698 static void gis_opengl_finalize(GObject *_opengl)
699 {
700         g_debug("GisOpenGL: finalize");
701         GisOpenGL *opengl = GIS_OPENGL(_opengl);
702         roam_sphere_free(opengl->sphere);
703         g_tree_destroy(opengl->objects);
704         g_mutex_free(opengl->sphere_lock);
705         G_OBJECT_CLASS(gis_opengl_parent_class)->finalize(_opengl);
706 }
707 static void gis_opengl_class_init(GisOpenGLClass *klass)
708 {
709         g_debug("GisOpenGL: class_init");
710         GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
711         gobject_class->finalize = gis_opengl_finalize;
712         gobject_class->dispose = gis_opengl_dispose;
713
714         GisViewerClass *viewer_class = GIS_VIEWER_CLASS(klass);
715         viewer_class->center_position   = gis_opengl_center_position;
716         viewer_class->project           = gis_opengl_project;
717         viewer_class->clear_height_func = gis_opengl_clear_height_func;
718         viewer_class->set_height_func   = gis_opengl_set_height_func;
719         viewer_class->add               = gis_opengl_add;
720         viewer_class->remove            = gis_opengl_remove;
721 }