]> Pileus Git - grits/blob - src/gis-opengl.c
Misc OpenGL refactoring and minor updates
[grits] / src / gis-opengl.c
1 /*
2  * Copyright (C) 2009 Andy Spencer <spenceal@rose-hulman.edu>
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[] = {0.0, 0.0, 0.0, 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         /* Misc */
106         gdouble rg   = MAX(0, 1-(elev/20000));
107         gdouble blue = MAX(0, 1-(elev/50000));
108         glClearColor(MIN(0.65,rg), MIN(0.65,rg), MIN(1,blue), 1.0f);
109         glColor4f(1, 1, 1, 1);
110
111         glDisable(GL_ALPHA_TEST);
112
113         glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
114         glEnable(GL_BLEND);
115
116 #ifndef ROAM_DEBUG
117         glCullFace(GL_BACK);
118         glEnable(GL_CULL_FACE);
119 #endif
120
121         glClearDepth(1.0);
122         glDepthFunc(GL_LEQUAL);
123         glEnable(GL_DEPTH_TEST);
124
125         glEnable(GL_LINE_SMOOTH);
126
127         glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
128         //glShadeModel(GL_FLAT);
129
130         roam_sphere_update_view(self->sphere);
131 }
132
133
134 /********************
135  * Object handleing *
136  ********************/
137 static void _draw_marker(GisOpenGL *self, GisMarker *marker)
138 {
139         GisPoint *point = gis_object_center(GIS_OBJECT(marker));
140         gdouble px, py, pz;
141         gis_viewer_project(GIS_VIEWER(self),
142                         point->lat, point->lon, point->elev,
143                         &px, &py, &pz);
144         if (pz > 1)
145                 return;
146
147         //g_debug("GisOpenGL: draw_marker - %s pz=%f ", marker->label, pz);
148
149         cairo_surface_t *surface = cairo_get_target(marker->cairo);
150         gdouble width  = cairo_image_surface_get_width(surface);
151         gdouble height = cairo_image_surface_get_height(surface);
152
153         glMatrixMode(GL_PROJECTION); glLoadIdentity();
154         glMatrixMode(GL_MODELVIEW);  glLoadIdentity();
155         glOrtho(0, GTK_WIDGET(self)->allocation.width,
156                 0, GTK_WIDGET(self)->allocation.height, -1, 1);
157         glTranslated(px - marker->xoff,
158                      py - marker->yoff, 0);
159
160         glDisable(GL_LIGHTING);
161         glDisable(GL_COLOR_MATERIAL);
162         glDisable(GL_DEPTH_TEST);
163         glEnable(GL_TEXTURE_2D);
164         glBindTexture(GL_TEXTURE_2D, marker->tex);
165         glBegin(GL_QUADS);
166         glTexCoord2f(1, 1); glVertex3f(width, 0     , 0);
167         glTexCoord2f(1, 0); glVertex3f(width, height, 0);
168         glTexCoord2f(0, 0); glVertex3f(0    , height, 0);
169         glTexCoord2f(0, 1); glVertex3f(0    , 0     , 0);
170         glEnd();
171 }
172
173 static void _draw_callback(GisOpenGL *self, GisCallback *callback)
174 {
175         callback->callback(callback, callback->user_data);
176 }
177
178 static void _draw_object(GisOpenGL *self, GisObject *object)
179 {
180         //g_debug("GisOpenGL: draw_object");
181         /* Skip out of range objects */
182         if (object->lod > 0) {
183                 gdouble eye[3], obj[3];
184                 gis_viewer_get_location(GIS_VIEWER(self), &eye[0], &eye[1], &eye[2]);
185                 lle2xyz(eye[0], eye[1], eye[2], &eye[0], &eye[1], &eye[2]);
186                 lle2xyz(object->center.lat, object->center.lon, object->center.elev,
187                         &obj[0], &obj[1], &obj[2]);
188                 gdouble dist = distd(obj, eye);
189                 if (object->lod < dist)
190                         return;
191         }
192
193         /* Draw */
194         glMatrixMode(GL_PROJECTION); glPushMatrix();
195         glMatrixMode(GL_MODELVIEW);  glPushMatrix();
196         glPushAttrib(GL_ALL_ATTRIB_BITS);
197         switch (object->type) {
198         case GIS_TYPE_MARKER:
199                 _draw_marker(self, GIS_MARKER(object));
200                 break;
201         case GIS_TYPE_CALLBACK:
202                 _draw_callback(self, GIS_CALLBACK(object));
203                 break;
204         default:
205                 break;
206         }
207         glPopAttrib();
208         glMatrixMode(GL_PROJECTION); glPopMatrix();
209         glMatrixMode(GL_MODELVIEW);  glPopMatrix();
210 }
211
212 static void _load_object(GisOpenGL *self, GisObject *object)
213 {
214         g_debug("GisOpenGL: load_object");
215         switch (object->type) {
216         case GIS_TYPE_MARKER: {
217                 GisMarker *marker = GIS_MARKER(object);
218                 cairo_surface_t *surface = cairo_get_target(marker->cairo);
219                 gdouble width  = cairo_image_surface_get_width(surface);
220                 gdouble height = cairo_image_surface_get_height(surface);
221
222                 _gis_opengl_begin(self);
223                 glEnable(GL_TEXTURE_2D);
224                 glGenTextures(1, &marker->tex);
225                 glBindTexture(GL_TEXTURE_2D, marker->tex);
226
227                 glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
228                 glPixelStorei(GL_PACK_ALIGNMENT, 1);
229                 glTexImage2D(GL_TEXTURE_2D, 0, 4, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE,
230                                 cairo_image_surface_get_data(surface));
231                 glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
232                 glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
233                 g_debug("load_texture: %d", marker->tex);
234                 _gis_opengl_end(self);
235                 break;
236         }
237         default:
238                 break;
239         }
240 }
241
242 static void _unload_object(GisOpenGL *self, GisObject *object)
243 {
244         g_debug("GisOpenGL: unload_object");
245         switch (object->type) {
246         case GIS_TYPE_MARKER: {
247                 GisMarker *marker = GIS_MARKER(object);
248                 g_debug("delete_texture: %d", marker->tex);
249                 glDeleteTextures(1, &marker->tex);
250                 break;
251         }
252         default:
253                 break;
254         }
255 }
256
257
258 /*************
259  * Callbacks *
260  *************/
261 /* The unsorted/sroted GLists are blank head nodes,
262  * This way us we can remove objects from the level just by fixing up links
263  * I.e. we don't need to do a lookup to remove an object if we have its GList */
264 struct RenderLevel {
265         GList unsorted;
266         GList sorted;
267 };
268
269 static void on_realize(GisOpenGL *self, gpointer _)
270 {
271         g_debug("GisOpenGL: on_realize");
272         _set_visuals(self);
273         roam_sphere_update_errors(self->sphere);
274 }
275 static gboolean on_configure(GisOpenGL *self, GdkEventConfigure *event, gpointer _)
276 {
277         g_debug("GisOpenGL: on_configure");
278         _gis_opengl_begin(self);
279
280         double width  = GTK_WIDGET(self)->allocation.width;
281         double height = GTK_WIDGET(self)->allocation.height;
282
283         /* Setup OpenGL Window */
284         glViewport(0, 0, width, height);
285         glMatrixMode(GL_PROJECTION);
286         glLoadIdentity();
287         double ang = atan(height/FOV_DIST);
288         gluPerspective(rad2deg(ang)*2, width/height, 1, 10*EARTH_R);
289
290 #ifndef ROAM_DEBUG
291         roam_sphere_update_errors(self->sphere);
292 #endif
293
294         _gis_opengl_end(self);
295         return FALSE;
296 }
297
298 static gboolean _draw_level(gpointer key, gpointer value, gpointer user_data)
299 {
300         g_debug("GisOpenGL: _draw_level - level=%-4d", (int)key);
301         GisOpenGL *self = user_data;
302         struct RenderLevel *level = value;
303         int nsorted = 0, nunsorted = 0;
304         GList *cur = NULL;
305
306         /* Draw opaque objects without sorting */
307         glDepthMask(TRUE);
308         glClear(GL_DEPTH_BUFFER_BIT);
309         for (cur = level->unsorted.next; cur; cur = cur->next, nunsorted++)
310                 _draw_object(self, GIS_OBJECT(cur->data));
311
312         /* Freeze depth buffer and draw transparent objects sorted */
313         /* TODO: sorting */
314         glDepthMask(FALSE);
315         for (cur = level->sorted.next; cur; cur = cur->next, nsorted++)
316                 _draw_object(self, GIS_OBJECT(cur->data));
317
318         /* TODO: Prune empty levels */
319
320         g_debug("GisOpenGL: _draw_level - drew %d,%d objects",
321                         nunsorted, nsorted);
322         return FALSE;
323 }
324
325 static gboolean on_expose(GisOpenGL *self, GdkEventExpose *event, gpointer _)
326 {
327         g_debug("GisOpenGL: on_expose - begin");
328         _gis_opengl_begin(self);
329
330         glClear(GL_COLOR_BUFFER_BIT);
331
332 #ifdef ROAM_DEBUG
333         _set_visuals(self);
334         glColor4f(0.0, 0.0, 9.0, 0.6);
335         glDisable(GL_TEXTURE_2D);
336         glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
337         roam_sphere_draw(self->sphere);
338         //roam_sphere_draw_normals(self->sphere);
339 #else
340         g_tree_foreach(self->objects, _draw_level, self);
341         if (self->wireframe) {
342                 _set_visuals(self);
343                 glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
344                 roam_sphere_draw(self->sphere);
345         }
346 #endif
347
348         GdkGLDrawable *gldrawable = gtk_widget_get_gl_drawable(GTK_WIDGET(self));
349         gdk_gl_drawable_swap_buffers(gldrawable);
350
351         _gis_opengl_end(self);
352         g_debug("GisOpenGL: on_expose - end\n");
353         return FALSE;
354 }
355
356 static gboolean on_key_press(GisOpenGL *self, GdkEventKey *event, gpointer _)
357 {
358         g_debug("GisOpenGL: on_key_press - key=%x, state=%x, plus=%x",
359                         event->keyval, event->state, GDK_plus);
360
361         guint kv = event->keyval;
362         gdk_threads_leave();
363         /* Testing */
364         if (kv == GDK_w) {
365                 self->wireframe = !self->wireframe;
366                 gtk_widget_queue_draw(GTK_WIDGET(self));
367         }
368 #ifdef ROAM_DEBUG
369         else if (kv == GDK_n) roam_sphere_split_one(self->sphere);
370         else if (kv == GDK_p) roam_sphere_merge_one(self->sphere);
371         else if (kv == GDK_r) roam_sphere_split_merge(self->sphere);
372         else if (kv == GDK_u) roam_sphere_update_errors(self->sphere);
373         gdk_threads_enter();
374         gtk_widget_queue_draw(GTK_WIDGET(self));
375 #else
376         gdk_threads_enter();
377 #endif
378         return FALSE;
379 }
380
381 static gboolean _update_errors_cb(gpointer sphere)
382 {
383         roam_sphere_update_errors(sphere);
384         return FALSE;
385 }
386 static void on_view_changed(GisOpenGL *self,
387                 gdouble _1, gdouble _2, gdouble _3)
388 {
389         g_debug("GisOpenGL: on_view_changed");
390         gdk_threads_enter();
391         _gis_opengl_begin(self);
392         _set_visuals(self);
393 #ifndef ROAM_DEBUG
394         g_idle_add_full(G_PRIORITY_HIGH_IDLE+30, _update_errors_cb, self->sphere, NULL);
395         //roam_sphere_update_errors(self->sphere);
396 #endif
397         _gis_opengl_end(self);
398         gdk_threads_leave();
399 }
400
401 static gboolean on_idle(GisOpenGL *self)
402 {
403         //g_debug("GisOpenGL: on_idle");
404         gdk_threads_enter();
405         _gis_opengl_begin(self);
406         if (roam_sphere_split_merge(self->sphere))
407                 gtk_widget_queue_draw(GTK_WIDGET(self));
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)
418 {
419         g_debug("GisOpenGL: new");
420         GisViewer *self = g_object_new(GIS_TYPE_OPENGL, NULL);
421         self->plugins = plugins;
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,
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] = {
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                 glEnable(GL_TEXTURE_2D);
486                 glBindTexture(GL_TEXTURE_2D, *(guint*)tile->data);
487                 glBegin(GL_TRIANGLES);
488                 glNormal3dv(tri->p.r->norm); glTexCoord2dv(xy[0]); glVertex3dv((double*)tri->p.r);
489                 glNormal3dv(tri->p.m->norm); glTexCoord2dv(xy[1]); glVertex3dv((double*)tri->p.m);
490                 glNormal3dv(tri->p.l->norm); glTexCoord2dv(xy[2]); glVertex3dv((double*)tri->p.l);
491                 glEnd();
492         }
493         g_list_free(triangles);
494 }
495
496 static void gis_opengl_render_tiles(GisViewer *_self, GisTile *tile)
497 {
498         GisOpenGL *self = GIS_OPENGL(_self);
499         /* Only render children if possible */
500         gboolean has_children = TRUE;
501         GisTile *child;
502         gis_tile_foreach(tile, child)
503                 if (!child || !child->data)
504                         has_children = FALSE;
505         if (has_children)
506                 /* Only render children */
507                 gis_tile_foreach(tile, child)
508                         gis_opengl_render_tiles(_self, child);
509         else
510                 /* No children, render this tile */
511                 gis_opengl_render_tile(_self, tile);
512 }
513
514 static void gis_opengl_set_height_func(GisViewer *_self, GisTile *tile,
515                 RoamHeightFunc height_func, gpointer user_data, gboolean update)
516 {
517         GisOpenGL *self = GIS_OPENGL(_self);
518         if (!tile)
519                 return;
520         /* TODO: get points? */
521         GList *triangles = roam_sphere_get_intersect(self->sphere,
522                         tile->edge.n, tile->edge.s, tile->edge.e, tile->edge.w);
523         for (GList *cur = triangles; cur; cur = cur->next) {
524                 RoamTriangle *tri = cur->data;
525                 RoamPoint *points[] = {tri->p.l, tri->p.m, tri->p.r, tri->split};
526                 for (int i = 0; i < G_N_ELEMENTS(points); i++) {
527                         points[i]->height_func = height_func;
528                         points[i]->height_data = user_data;
529                         roam_point_update_height(points[i]);
530                 }
531         }
532         g_list_free(triangles);
533 }
534
535 static void _gis_opengl_clear_height_func_rec(RoamTriangle *root)
536 {
537         if (!root)
538                 return;
539         RoamPoint *points[] = {root->p.l, root->p.m, root->p.r, root->split};
540         for (int i = 0; i < G_N_ELEMENTS(points); i++) {
541                 points[i]->height_func = NULL;
542                 points[i]->height_data = NULL;
543                 roam_point_update_height(points[i]);
544         }
545         _gis_opengl_clear_height_func_rec(root->kids[0]);
546         _gis_opengl_clear_height_func_rec(root->kids[1]);
547 }
548
549 static void gis_opengl_clear_height_func(GisViewer *_self)
550 {
551         GisOpenGL *self = GIS_OPENGL(_self);
552         for (int i = 0; i < G_N_ELEMENTS(self->sphere->roots); i++)
553                 _gis_opengl_clear_height_func_rec(self->sphere->roots[i]);
554 }
555
556 static void gis_opengl_begin(GisViewer *_self)
557 {
558         g_assert(GIS_IS_OPENGL(_self));
559         _gis_opengl_begin(GIS_OPENGL(_self));
560 }
561
562 static void gis_opengl_end(GisViewer *_self)
563 {
564         g_assert(GIS_IS_OPENGL(_self));
565         _gis_opengl_end(GIS_OPENGL(_self));
566 }
567
568 static gpointer gis_opengl_add(GisViewer *_self, GisObject *object,
569                 gint key, gboolean sort)
570 {
571         g_assert(GIS_IS_OPENGL(_self));
572         GisOpenGL *self = GIS_OPENGL(_self);
573         _load_object(self, object);
574         struct RenderLevel *level = g_tree_lookup(self->objects, (gpointer)key);
575         if (!level) {
576                 level = g_new0(struct RenderLevel, 1);
577                 g_tree_insert(self->objects, (gpointer)key, level);
578         }
579         GList *list = sort ? &level->sorted : &level->unsorted;
580         list->next = g_list_prepend(list->next, object);
581         return list->next;
582 }
583
584 static void gis_opengl_remove(GisViewer *_self, gpointer _link)
585 {
586         g_assert(GIS_IS_OPENGL(_self));
587         GList *link = _link;
588         GisOpenGL *self = GIS_OPENGL(_self);
589         _unload_object(self, link->data);
590         /* Just unlink and free it (blowup link to avoid warnings) */
591         link = g_list_delete_link(NULL, link);
592 }
593
594 /****************
595  * GObject code *
596  ****************/
597 static int _objects_cmp(gconstpointer _a, gconstpointer _b)
598 {
599         gint a = (int)_a, b = (int)_b;
600         return a < b ? -1 :
601                a > b ?  1 : 0;
602 }
603
604 G_DEFINE_TYPE(GisOpenGL, gis_opengl, GIS_TYPE_VIEWER);
605 static void gis_opengl_init(GisOpenGL *self)
606 {
607         g_debug("GisOpenGL: init");
608         /* OpenGL setup */
609         GdkGLConfig *glconfig = gdk_gl_config_new_by_mode(
610                         GDK_GL_MODE_RGBA   | GDK_GL_MODE_DEPTH |
611                         GDK_GL_MODE_DOUBLE | GDK_GL_MODE_ALPHA);
612         if (!glconfig)
613                 g_error("Failed to create glconfig");
614         if (!gtk_widget_set_gl_capability(GTK_WIDGET(self),
615                                 glconfig, NULL, TRUE, GDK_GL_RGBA_TYPE))
616                 g_error("GL lacks required capabilities");
617         g_object_unref(glconfig);
618
619         gtk_widget_set_size_request(GTK_WIDGET(self), 600, 550);
620         gtk_widget_set_events(GTK_WIDGET(self),
621                         GDK_BUTTON_PRESS_MASK |
622                         GDK_ENTER_NOTIFY_MASK |
623                         GDK_KEY_PRESS_MASK);
624         g_object_set(self, "can-focus", TRUE, NULL);
625
626         self->objects = g_tree_new(_objects_cmp);
627         self->sphere = roam_sphere_new(self);
628
629 #ifndef ROAM_DEBUG
630         self->sm_source[0] = g_timeout_add_full(G_PRIORITY_HIGH_IDLE+30, 33,  (GSourceFunc)on_idle, self, NULL);
631         self->sm_source[1] = g_timeout_add_full(G_PRIORITY_HIGH_IDLE+10, 500, (GSourceFunc)on_idle, self, NULL);
632 #endif
633
634         g_signal_connect(self, "realize",          G_CALLBACK(on_realize),      NULL);
635         g_signal_connect(self, "configure-event",  G_CALLBACK(on_configure),    NULL);
636         g_signal_connect(self, "expose-event",     G_CALLBACK(on_expose),       NULL);
637
638         g_signal_connect(self, "key-press-event",  G_CALLBACK(on_key_press),    NULL);
639
640         g_signal_connect(self, "location-changed", G_CALLBACK(on_view_changed), NULL);
641         g_signal_connect(self, "rotation-changed", G_CALLBACK(on_view_changed), NULL);
642 }
643 static void gis_opengl_dispose(GObject *_self)
644 {
645         g_debug("GisOpenGL: dispose");
646         GisOpenGL *self = GIS_OPENGL(_self);
647         if (self->sm_source[0]) {
648                 g_source_remove(self->sm_source[0]);
649                 self->sm_source[0] = 0;
650         }
651         if (self->sm_source[1]) {
652                 g_source_remove(self->sm_source[1]);
653                 self->sm_source[1] = 0;
654         }
655         if (self->sphere) {
656                 roam_sphere_free(self->sphere);
657                 self->sphere = NULL;
658         }
659         /* TODO: Cleanup/free objects tree */
660         G_OBJECT_CLASS(gis_opengl_parent_class)->dispose(_self);
661 }
662 static void gis_opengl_finalize(GObject *_self)
663 {
664         g_debug("GisViewer: finalize");
665         GisOpenGL *self = GIS_OPENGL(_self);
666         G_OBJECT_CLASS(gis_opengl_parent_class)->finalize(_self);
667 }
668 static void gis_opengl_class_init(GisOpenGLClass *klass)
669 {
670         g_debug("GisOpenGL: class_init");
671         GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
672         gobject_class->dispose     = gis_opengl_dispose;
673
674         GisViewerClass *viewer_class = GIS_VIEWER_CLASS(klass);
675         viewer_class->center_position   = gis_opengl_center_position;
676         viewer_class->project           = gis_opengl_project;
677         viewer_class->clear_height_func = gis_opengl_clear_height_func;
678         viewer_class->set_height_func   = gis_opengl_set_height_func;
679         viewer_class->render_tile       = gis_opengl_render_tile;
680         viewer_class->render_tiles      = gis_opengl_render_tiles;
681         viewer_class->begin             = gis_opengl_begin;
682         viewer_class->end               = gis_opengl_end;
683         viewer_class->add               = gis_opengl_add;
684         viewer_class->remove            = gis_opengl_remove;
685 }