2 * Copyright (C) 2009-2011 Andy Spencer <andy753421@gmail.com>
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.
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.
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/>.
19 * SECTION:grits-opengl
20 * @short_description: OpenGL based virtual globe
22 * #GritsOpenGL is the core rendering engine used by grits. Theoretically other
23 * renderers could be writte, but they have not been. GritsOpenGL uses the ROAM
24 * algorithm for updating surface mesh the planet. The only thing GritsOpenGL
25 * can actually render on it's own is a wireframe of a sphere.
27 * GritsOpenGL requires (at least) OpenGL 2.0.
33 #include <gdk/gdkkeysyms.h>
36 #include "grits-opengl.h"
37 #include "grits-util.h"
43 /* Tessellation, "finding intersecting triangles" */
44 /* http://research.microsoft.com/pubs/70307/tr-2006-81.pdf */
45 /* http://www.opengl.org/wiki/Alpha_Blending */
47 /* The unsorted/sroted GLists are blank head nodes,
48 * This way us we can remove objects from the level just by fixing up links
49 * I.e. we don't need to do a lookup to remove an object if we have its GList */
58 static void _set_visuals(GritsOpenGL *opengl)
60 glMatrixMode(GL_MODELVIEW);
64 double lat, lon, elev, rx, ry, rz;
65 grits_viewer_get_location(GRITS_VIEWER(opengl), &lat, &lon, &elev);
66 grits_viewer_get_rotation(GRITS_VIEWER(opengl), &rx, &ry, &rz);
67 glRotatef(rx, 1, 0, 0);
68 glRotatef(rz, 0, 0, 1);
72 float light_ambient[] = {0.7f, 0.7f, 0.7f, 1.0f};
73 float light_diffuse[] = {2.0f, 2.0f, 2.0f, 1.0f};
75 float light_ambient[] = {0.2f, 0.2f, 0.2f, 1.0f};
76 float light_diffuse[] = {0.8f, 0.8f, 0.8f, 1.0f};
78 float light_position[] = {-13*EARTH_R, 1*EARTH_R, 3*EARTH_R, 1.0f};
79 glLightfv(GL_LIGHT0, GL_AMBIENT, light_ambient);
80 glLightfv(GL_LIGHT0, GL_DIFFUSE, light_diffuse);
81 glLightfv(GL_LIGHT0, GL_POSITION, light_position);
83 glEnable(GL_LIGHTING);
85 float material_ambient[] = {1.0, 1.0, 1.0, 1.0};
86 float material_diffuse[] = {1.0, 1.0, 1.0, 1.0};
87 float material_specular[] = {0.0, 0.0, 0.0, 1.0};
88 float material_emission[] = {0.0, 0.0, 0.0, 1.0};
89 glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT, material_ambient);
90 glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE, material_diffuse);
91 glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, material_specular);
92 glMaterialfv(GL_FRONT_AND_BACK, GL_EMISSION, material_emission);
93 glDisable(GL_TEXTURE_2D);
94 glDisable(GL_COLOR_MATERIAL);
97 glTranslatef(0, 0, -elev2rad(elev));
98 glRotatef(lat, 1, 0, 0);
99 glRotatef(-lon, 0, 1, 0);
101 glDisable(GL_ALPHA_TEST);
103 glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
108 glEnable(GL_CULL_FACE);
111 glDepthFunc(GL_LEQUAL);
112 glEnable(GL_DEPTH_TEST);
115 glEnable(GL_LINE_SMOOTH);
117 glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
118 //glShadeModel(GL_FLAT);
120 g_mutex_lock(opengl->sphere_lock);
121 roam_sphere_update_view(opengl->sphere);
122 g_mutex_unlock(opengl->sphere_lock);
125 static gboolean _foreach_object_cb(gpointer key, gpointer value, gpointer pointers)
127 struct RenderLevel *level = value;
128 GFunc user_func = ((gpointer*)pointers)[0];
129 gpointer user_data = ((gpointer*)pointers)[1];
130 for (GList *cur = level->unsorted.next; cur; cur = cur->next)
131 user_func(cur->data, user_data);
132 for (GList *cur = level->sorted.next; cur; cur = cur->next)
133 user_func(cur->data, user_data);
137 static void _foreach_object(GritsOpenGL *opengl, GFunc func, gpointer user_data)
139 gpointer pointers[2] = {func, user_data};
140 g_tree_foreach(opengl->objects, _foreach_object_cb, pointers);
143 static void _add_object(GritsObject *object, GPtrArray *array)
145 g_ptr_array_add(array, object);
148 static GPtrArray *_objects_to_array(GritsOpenGL *opengl)
150 GPtrArray *array = g_ptr_array_new();
151 _foreach_object(opengl, (GFunc)_add_object, array);
158 static gboolean on_configure(GritsOpenGL *opengl, GdkEventConfigure *event, gpointer _)
160 g_debug("GritsOpenGL: on_configure");
162 double width = GTK_WIDGET(opengl)->allocation.width;
163 double height = GTK_WIDGET(opengl)->allocation.height;
165 /* Setup OpenGL Window */
166 glViewport(0, 0, width, height);
167 glMatrixMode(GL_PROJECTION);
169 double ang = atan(height/FOV_DIST);
170 gluPerspective(rad2deg(ang)*2, width/height, 10, 100*EARTH_R);
173 g_mutex_lock(opengl->sphere_lock);
174 roam_sphere_update_errors(opengl->sphere);
175 g_mutex_unlock(opengl->sphere_lock);
181 static gboolean _draw_level(gpointer key, gpointer value, gpointer user_data)
183 g_debug("GritsOpenGL: _draw_level - level=%-4ld", (glong)key);
184 GritsOpenGL *opengl = user_data;
185 struct RenderLevel *level = value;
186 int nsorted = 0, nunsorted = 0;
189 /* Draw opaque objects without sorting */
191 glClear(GL_DEPTH_BUFFER_BIT);
192 for (cur = level->unsorted.next; cur; cur = cur->next, nunsorted++)
193 grits_object_draw(GRITS_OBJECT(cur->data), opengl);
195 /* Freeze depth buffer and draw transparent objects sorted */
197 //glDepthMask(FALSE);
198 glAlphaFunc(GL_GREATER, 0.1);
199 for (cur = level->sorted.next; cur; cur = cur->next, nsorted++)
200 grits_object_draw(GRITS_OBJECT(cur->data), opengl);
202 /* TODO: Prune empty levels */
204 g_debug("GritsOpenGL: _draw_level - drew %d,%d objects",
209 static gboolean on_expose(GritsOpenGL *opengl, GdkEventExpose *event, gpointer _)
211 g_debug("GritsOpenGL: on_expose - begin");
213 glClear(GL_COLOR_BUFFER_BIT);
215 _set_visuals(opengl);
217 glColor4f(1.0, 1.0, 1.0, 1.0);
219 glDisable(GL_TEXTURE_2D);
220 glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
221 roam_sphere_draw(opengl->sphere);
223 //roam_sphere_draw_normals(opengl->sphere);
225 g_mutex_lock(opengl->objects_lock);
226 g_tree_foreach(opengl->objects, _draw_level, opengl);
227 if (opengl->wireframe) {
228 glClear(GL_DEPTH_BUFFER_BIT);
229 glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
230 roam_sphere_draw(opengl->sphere);
231 g_tree_foreach(opengl->objects, _draw_level, opengl);
233 g_mutex_unlock(opengl->objects_lock);
236 gtk_gl_end(GTK_WIDGET(opengl));
238 g_debug("GritsOpenGL: on_expose - end\n");
242 static gboolean on_motion_notify(GritsOpenGL *opengl, GdkEventMotion *event, gpointer _)
244 gdouble height = GTK_WIDGET(opengl)->allocation.height;
245 gdouble gl_x = event->x;
246 gdouble gl_y = height - event->y;
250 gdouble projection[16];
251 glGetIntegerv(GL_VIEWPORT, viewport);
252 glGetDoublev(GL_PROJECTION_MATRIX, projection);
254 glMatrixMode(GL_PROJECTION);
257 gluPickMatrix(gl_x, gl_y, 2, 2, viewport);
258 glMultMatrixd(projection);
260 /* Prepare for picking */
261 guint buffer[100][4] = {};
262 glSelectBuffer(G_N_ELEMENTS(buffer), (guint*)buffer);
263 glRenderMode(GL_SELECT);
267 g_mutex_lock(opengl->objects_lock);
268 GPtrArray *objects = _objects_to_array(opengl);
269 for (guint i = 0; i < objects->len; i++) {
271 GritsObject *object = objects->pdata[i];
272 object->state.picked = FALSE;
273 grits_object_pick(object, opengl);
276 int hits = glRenderMode(GL_RENDER);
277 g_debug("GritsOpenGL: on_motion_notify - hits=%d ev=%.0lf,%.0lf",
279 for (int i = 0; i < hits; i++) {
280 //g_debug("\tHit: %d", i);
281 //g_debug("\t\tcount: %d", buffer[i][0]);
282 //g_debug("\t\tz1: %f", (float)buffer[i][1]/0x7fffffff);
283 //g_debug("\t\tz2: %f", (float)buffer[i][2]/0x7fffffff);
284 //g_debug("\t\tname: %p", (gpointer)buffer[i][3]);
285 guint index = buffer[i][3];
286 GritsObject *object = objects->pdata[index];
287 object->state.picked = TRUE;
289 for (guint i = 0; i < objects->len; i++) {
290 GritsObject *object = objects->pdata[i];
291 grits_object_set_pointer(object, object->state.picked);
293 g_ptr_array_free(objects, TRUE);
294 g_mutex_unlock(opengl->objects_lock);
297 glMatrixMode(GL_PROJECTION);
303 static gboolean on_key_press(GritsOpenGL *opengl, GdkEventKey *event, gpointer _)
305 g_debug("GritsOpenGL: on_key_press - key=%x, state=%x, plus=%x",
306 event->keyval, event->state, GDK_plus);
308 guint kv = event->keyval;
311 opengl->wireframe = !opengl->wireframe;
312 gtk_widget_queue_draw(GTK_WIDGET(opengl));
315 else if (kv == GDK_n) roam_sphere_split_one(opengl->sphere);
316 else if (kv == GDK_p) roam_sphere_merge_one(opengl->sphere);
317 else if (kv == GDK_r) roam_sphere_split_merge(opengl->sphere);
318 else if (kv == GDK_u) roam_sphere_update_errors(opengl->sphere);
319 gtk_widget_queue_draw(GTK_WIDGET(opengl));
324 static gboolean on_chained_event(GritsOpenGL *opengl, GdkEvent *event, gpointer _)
326 _foreach_object(opengl, (GFunc)grits_object_event, event);
330 static gboolean _update_errors_cb(gpointer _opengl)
332 GritsOpenGL *opengl = _opengl;
333 g_mutex_lock(opengl->sphere_lock);
334 roam_sphere_update_errors(opengl->sphere);
335 g_mutex_unlock(opengl->sphere_lock);
336 opengl->ue_source = 0;
339 static void on_view_changed(GritsOpenGL *opengl,
340 gdouble _1, gdouble _2, gdouble _3)
342 g_debug("GritsOpenGL: on_view_changed");
343 _set_visuals(opengl);
345 if (!opengl->ue_source)
346 opengl->ue_source = g_idle_add_full(G_PRIORITY_HIGH_IDLE+30,
347 _update_errors_cb, opengl, NULL);
348 //roam_sphere_update_errors(opengl->sphere);
350 (void)_update_errors_cb;
354 static gboolean on_idle(GritsOpenGL *opengl)
356 //g_debug("GritsOpenGL: on_idle");
357 g_mutex_lock(opengl->sphere_lock);
358 if (roam_sphere_split_merge(opengl->sphere))
359 gtk_widget_queue_draw(GTK_WIDGET(opengl));
360 g_mutex_unlock(opengl->sphere_lock);
364 static void on_realize(GritsOpenGL *opengl, gpointer _)
366 g_debug("GritsOpenGL: on_realize");
367 gtk_gl_begin(GTK_WIDGET(opengl));
369 /* Connect signals and idle functions now that opengl is fully initialized */
370 gtk_widget_add_events(GTK_WIDGET(opengl), GDK_KEY_PRESS_MASK);
371 g_signal_connect(opengl, "configure-event", G_CALLBACK(on_configure), NULL);
372 g_signal_connect(opengl, "expose-event", G_CALLBACK(on_expose), NULL);
374 g_signal_connect(opengl, "key-press-event", G_CALLBACK(on_key_press), NULL);
376 g_signal_connect(opengl, "location-changed", G_CALLBACK(on_view_changed), NULL);
377 g_signal_connect(opengl, "rotation-changed", G_CALLBACK(on_view_changed), NULL);
379 g_signal_connect(opengl, "motion-notify-event", G_CALLBACK(on_motion_notify), NULL);
380 g_signal_connect_after(opengl, "key-press-event", G_CALLBACK(on_chained_event), NULL);
381 g_signal_connect_after(opengl, "key-release-event", G_CALLBACK(on_chained_event), NULL);
382 g_signal_connect_after(opengl, "button-press-event", G_CALLBACK(on_chained_event), NULL);
383 g_signal_connect_after(opengl, "button-release-event", G_CALLBACK(on_chained_event), NULL);
384 g_signal_connect_after(opengl, "motion-notify-event", G_CALLBACK(on_chained_event), NULL);
387 opengl->sm_source[0] = g_timeout_add_full(G_PRIORITY_HIGH_IDLE+30, 33, (GSourceFunc)on_idle, opengl, NULL);
388 opengl->sm_source[1] = g_timeout_add_full(G_PRIORITY_HIGH_IDLE+10, 500, (GSourceFunc)on_idle, opengl, NULL);
391 (void)_update_errors_cb;
394 /* Re-queue resize incase configure was triggered before realize */
395 gtk_widget_queue_resize(GTK_WIDGET(opengl));
398 /*********************
399 * GritsViewer methods *
400 *********************/
403 * @plugins: the plugins store to use
404 * @prefs: the preferences object to use
406 * Create a new OpenGL renderer.
408 * Returns: the new #GritsOpenGL
410 GritsViewer *grits_opengl_new(GritsPlugins *plugins, GritsPrefs *prefs)
412 g_debug("GritsOpenGL: new");
413 GritsViewer *opengl = g_object_new(GRITS_TYPE_OPENGL, NULL);
414 grits_viewer_setup(opengl, plugins, prefs);
418 static void grits_opengl_center_position(GritsViewer *_opengl, gdouble lat, gdouble lon, gdouble elev)
420 glRotatef(lon, 0, 1, 0);
421 glRotatef(-lat, 1, 0, 0);
422 glTranslatef(0, 0, elev2rad(elev));
425 static void grits_opengl_project(GritsViewer *_opengl,
426 gdouble lat, gdouble lon, gdouble elev,
427 gdouble *px, gdouble *py, gdouble *pz)
429 GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
431 lle2xyz(lat, lon, elev, &x, &y, &z);
433 opengl->sphere->view->model,
434 opengl->sphere->view->proj,
435 opengl->sphere->view->view,
439 static void grits_opengl_set_height_func(GritsViewer *_opengl, GritsBounds *bounds,
440 RoamHeightFunc height_func, gpointer user_data, gboolean update)
442 GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
443 /* TODO: get points? */
444 g_mutex_lock(opengl->sphere_lock);
445 GList *triangles = roam_sphere_get_intersect(opengl->sphere, TRUE,
446 bounds->n, bounds->s, bounds->e, bounds->w);
447 for (GList *cur = triangles; cur; cur = cur->next) {
448 RoamTriangle *tri = cur->data;
449 RoamPoint *points[] = {tri->p.l, tri->p.m, tri->p.r, tri->split};
450 for (int i = 0; i < G_N_ELEMENTS(points); i++) {
451 if (bounds->n >= points[i]->lat && points[i]->lat >= bounds->s &&
452 bounds->e >= points[i]->lon && points[i]->lon >= bounds->w) {
453 points[i]->height_func = height_func;
454 points[i]->height_data = user_data;
455 roam_point_update_height(points[i]);
459 g_list_free(triangles);
460 g_mutex_unlock(opengl->sphere_lock);
463 static void _grits_opengl_clear_height_func_rec(RoamTriangle *root)
467 RoamPoint *points[] = {root->p.l, root->p.m, root->p.r, root->split};
468 for (int i = 0; i < G_N_ELEMENTS(points); i++) {
469 points[i]->height_func = NULL;
470 points[i]->height_data = NULL;
471 roam_point_update_height(points[i]);
473 _grits_opengl_clear_height_func_rec(root->kids[0]);
474 _grits_opengl_clear_height_func_rec(root->kids[1]);
477 static void grits_opengl_clear_height_func(GritsViewer *_opengl)
479 GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
480 for (int i = 0; i < G_N_ELEMENTS(opengl->sphere->roots); i++)
481 _grits_opengl_clear_height_func_rec(opengl->sphere->roots[i]);
484 static gpointer grits_opengl_add(GritsViewer *_opengl, GritsObject *object,
485 gint key, gboolean sort)
487 g_assert(GRITS_IS_OPENGL(_opengl));
488 GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
489 g_mutex_lock(opengl->objects_lock);
490 struct RenderLevel *level = g_tree_lookup(opengl->objects, (gpointer)(gintptr)key);
492 level = g_new0(struct RenderLevel, 1);
493 g_tree_insert(opengl->objects, (gpointer)(gintptr)key, level);
495 GList *list = sort ? &level->sorted : &level->unsorted;
496 /* Put the link in the list */
497 GList *link = g_new0(GList, 1);
500 link->next = list->next;
502 list->next->prev = link;
504 g_mutex_unlock(opengl->objects_lock);
508 static GritsObject *grits_opengl_remove(GritsViewer *_opengl, GritsObject *object)
510 g_assert(GRITS_IS_OPENGL(_opengl));
511 GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
512 GList *link = object->ref;
513 g_mutex_lock(opengl->objects_lock);
514 /* Just unlink and free it, link->prev is assured */
515 link->prev->next = link->next;
517 link->next->prev = link->prev;
518 g_mutex_unlock(opengl->objects_lock);
520 object->viewer = NULL;
522 g_object_unref(object);
529 static int _objects_cmp(gconstpointer _a, gconstpointer _b, gpointer _)
531 gintptr a = (gintptr)_a, b = (gintptr)_b;
535 static void _objects_free(gpointer value)
537 struct RenderLevel *level = value;
538 if (level->sorted.next)
539 g_list_free(level->sorted.next);
540 if (level->unsorted.next)
541 g_list_free(level->unsorted.next);
545 G_DEFINE_TYPE(GritsOpenGL, grits_opengl, GRITS_TYPE_VIEWER);
546 static void grits_opengl_init(GritsOpenGL *opengl)
548 g_debug("GritsOpenGL: init");
549 opengl->objects = g_tree_new_full(_objects_cmp, NULL, NULL, _objects_free);
550 opengl->objects_lock = g_mutex_new();
551 opengl->sphere = roam_sphere_new(opengl);
552 opengl->sphere_lock = g_mutex_new();
553 gtk_gl_enable(GTK_WIDGET(opengl));
554 g_signal_connect(opengl, "realize", G_CALLBACK(on_realize), NULL);
556 static void grits_opengl_dispose(GObject *_opengl)
558 g_debug("GritsOpenGL: dispose");
559 GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
560 if (opengl->sm_source[0]) {
561 g_source_remove(opengl->sm_source[0]);
562 opengl->sm_source[0] = 0;
564 if (opengl->sm_source[1]) {
565 g_source_remove(opengl->sm_source[1]);
566 opengl->sm_source[1] = 0;
568 if (opengl->ue_source) {
569 g_source_remove(opengl->ue_source);
570 opengl->ue_source = 0;
572 G_OBJECT_CLASS(grits_opengl_parent_class)->dispose(_opengl);
574 static void grits_opengl_finalize(GObject *_opengl)
576 g_debug("GritsOpenGL: finalize");
577 GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
578 roam_sphere_free(opengl->sphere);
579 g_tree_destroy(opengl->objects);
580 g_mutex_free(opengl->objects_lock);
581 g_mutex_free(opengl->sphere_lock);
582 G_OBJECT_CLASS(grits_opengl_parent_class)->finalize(_opengl);
584 static void grits_opengl_class_init(GritsOpenGLClass *klass)
586 g_debug("GritsOpenGL: class_init");
587 GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
588 gobject_class->finalize = grits_opengl_finalize;
589 gobject_class->dispose = grits_opengl_dispose;
591 GritsViewerClass *viewer_class = GRITS_VIEWER_CLASS(klass);
592 viewer_class->center_position = grits_opengl_center_position;
593 viewer_class->project = grits_opengl_project;
594 viewer_class->clear_height_func = grits_opengl_clear_height_func;
595 viewer_class->set_height_func = grits_opengl_set_height_func;
596 viewer_class->add = grits_opengl_add;
597 viewer_class->remove = grits_opengl_remove;