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

   1 /*
   2  * Copyright (C) 2009-2011 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:grits-opengl
  20  * @short_description: OpenGL based virtual globe
  21  *
  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.
  26  *
  27  * GritsOpenGL 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
  36 #include "grits-opengl.h"
  37 #include "grits-util.h"
  38 #include "gtkgl.h"
  39 #include "roam.h"
  40
  41 // #define ROAM_DEBUG
  42
  43 /* Tessellation, "finding intersecting triangles" */
  44 /* http://research.microsoft.com/pubs/70307/tr-2006-81.pdf */
  45 /* http://www.opengl.org/wiki/Alpha_Blending */
  46
  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 */
  50 struct RenderLevel {
  51         GList unsorted;
  52         GList sorted;
  53 };
  54
  55 /***********
  56  * Helpers *
  57  ***********/
  58 static void _set_visuals(GritsOpenGL *opengl)
  59 {
  60         double lat, lon, elev, rx, ry, rz;
  61         grits_viewer_get_location(GRITS_VIEWER(opengl), &lat, &lon, &elev);
  62         grits_viewer_get_rotation(GRITS_VIEWER(opengl), &rx, &ry, &rz);
  63
  64         /* Set projection and clipping planes */
  65         glMatrixMode(GL_PROJECTION);
  66         glLoadIdentity();
  67
  68         double width  = GTK_WIDGET(opengl)->allocation.width;
  69         double height = GTK_WIDGET(opengl)->allocation.height;
  70         double ang    = atan((height/2)/FOV_DIST)*2;
  71         double atmos  = 100000;
  72         double near   = MAX(elev*0.75 - atmos, 50); // View 100km of atmosphere
  73         double far    = elev + 2*EARTH_R + atmos;   // on both sides of the earth
  74
  75         grits_viewer_get_location(GRITS_VIEWER(opengl), &lat, &lon, &elev);
  76         glViewport(0, 0, width, height);
  77         gluPerspective(rad2deg(ang), width/height, near, far);
  78
  79         /* Setup camera and lighting */
  80         glMatrixMode(GL_MODELVIEW);
  81         glLoadIdentity();
  82
  83         /* Camera 1 */
  84         glRotatef(rx, 1, 0, 0);
  85         glRotatef(rz, 0, 0, 1);
  86
  87         /* Lighting */
  88 #ifdef ROAM_DEBUG
  89         float light_ambient[]  = {0.7f, 0.7f, 0.7f, 1.0f};
  90         float light_diffuse[]  = {2.0f, 2.0f, 2.0f, 1.0f};
  91 #else
  92         float light_ambient[]  = {0.2f, 0.2f, 0.2f, 1.0f};
  93         float light_diffuse[]  = {0.8f, 0.8f, 0.8f, 1.0f};
  94 #endif
  95         float light_position[] = {-13*EARTH_R, 1*EARTH_R, 3*EARTH_R, 1.0f};
  96         glLightfv(GL_LIGHT0, GL_AMBIENT,  light_ambient);
  97         glLightfv(GL_LIGHT0, GL_DIFFUSE,  light_diffuse);
  98         glLightfv(GL_LIGHT0, GL_POSITION, light_position);
  99         glEnable(GL_LIGHT0);
 100         glEnable(GL_LIGHTING);
 101
 102         float material_ambient[]  = {1.0, 1.0, 1.0, 1.0};
 103         float material_diffuse[]  = {1.0, 1.0, 1.0, 1.0};
 104         float material_specular[] = {0.0, 0.0, 0.0, 1.0};
 105         float material_emission[] = {0.0, 0.0, 0.0, 1.0};
 106         glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT,  material_ambient);
 107         glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE,  material_diffuse);
 108         glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, material_specular);
 109         glMaterialfv(GL_FRONT_AND_BACK, GL_EMISSION, material_emission);
 110         glDisable(GL_TEXTURE_2D);
 111         glDisable(GL_COLOR_MATERIAL);
 112
 113         /* Camera 2 */
 114         glTranslatef(0, 0, -elev2rad(elev));
 115         glRotatef(lat, 1, 0, 0);
 116         glRotatef(-lon, 0, 1, 0);
 117
 118         glDisable(GL_ALPHA_TEST);
 119
 120         glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 121         glEnable(GL_BLEND);
 122
 123 #ifndef ROAM_DEBUG
 124         glCullFace(GL_BACK);
 125         glEnable(GL_CULL_FACE);
 126
 127         glClearDepth(1.0);
 128         glDepthFunc(GL_LEQUAL);
 129         glEnable(GL_DEPTH_TEST);
 130 #endif
 131
 132         glEnable(GL_LINE_SMOOTH);
 133
 134         glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
 135         //glShadeModel(GL_FLAT);
 136
 137         g_mutex_lock(opengl->sphere_lock);
 138         roam_sphere_update_view(opengl->sphere);
 139         g_mutex_unlock(opengl->sphere_lock);
 140 }
 141
 142 typedef void (*GritsLevelFunc)(GritsObject *obj, gpointer user_data, gint level, gboolean sorted);
 143
 144 static gboolean _foreach_object_cb(gpointer key, gpointer value, gpointer pointers)
 145 {
 146         struct RenderLevel *level = value;
 147         GritsLevelFunc user_func = ((gpointer*)pointers)[0];
 148         gpointer       user_data = ((gpointer*)pointers)[1];
 149         for (GList *cur = level->unsorted.next; cur; cur = cur->next)
 150                 user_func(cur->data, user_data, (gint)key, FALSE);
 151         for (GList *cur = level->sorted.next;   cur; cur = cur->next)
 152                 user_func(cur->data, user_data, (gint)key, TRUE);
 153         return FALSE;
 154 }
 155
 156 static void _foreach_object(GritsOpenGL *opengl, GritsLevelFunc func, gpointer user_data)
 157 {
 158         gpointer pointers[2] = {func, user_data};
 159         g_tree_foreach(opengl->objects, _foreach_object_cb, pointers);
 160 }
 161
 162 static void _add_object_world(GritsObject *object, GPtrArray *array, gint level, gboolean sorted)
 163 {
 164         if (level < GRITS_LEVEL_HUD)
 165                 g_ptr_array_add(array, object);
 166 }
 167
 168 static void _add_object_ortho(GritsObject *object, GPtrArray *array, gint level, gboolean sorted)
 169 {
 170         if (level >= GRITS_LEVEL_HUD)
 171                 g_ptr_array_add(array, object);
 172 }
 173
 174 static GPtrArray *_objects_to_array(GritsOpenGL *opengl, gboolean ortho)
 175 {
 176         GPtrArray *array = g_ptr_array_new();
 177         GritsLevelFunc func = (GritsLevelFunc)(ortho ? _add_object_ortho : _add_object_world);
 178         _foreach_object(opengl, func, array);
 179         return array;
 180 }
 181
 182 /*************
 183  * Callbacks *
 184  *************/
 185 static gboolean on_configure(GritsOpenGL *opengl, GdkEventConfigure *event, gpointer _)
 186 {
 187         g_debug("GritsOpenGL: on_configure");
 188
 189         _set_visuals(opengl);
 190 #ifndef ROAM_DEBUG
 191         g_mutex_lock(opengl->sphere_lock);
 192         roam_sphere_update_errors(opengl->sphere);
 193         g_mutex_unlock(opengl->sphere_lock);
 194 #endif
 195
 196         return FALSE;
 197 }
 198
 199 static gint run_picking(GritsOpenGL *opengl, GPtrArray *objects)
 200 {
 201         /* Setup picking buffers */
 202         guint buffer[100][4] = {};
 203         glSelectBuffer(G_N_ELEMENTS(buffer), (guint*)buffer);
 204         if (!opengl->pickmode)
 205                 glRenderMode(GL_SELECT);
 206         glInitNames();
 207
 208         /* Render/pick objects */
 209         for (guint i = 0; i < objects->len; i++) {
 210                 glPushName(i);
 211                 GritsObject *object = objects->pdata[i];
 212                 object->state.picked = FALSE;
 213                 grits_object_pick(object, opengl);
 214                 glPopName();
 215         }
 216
 217         int hits = glRenderMode(GL_RENDER);
 218
 219         /* Process hits */
 220         for (int i = 0; i < hits; i++) {
 221                 //g_debug("\tHit: %d",     i);
 222                 //g_debug("\t\tcount: %d", buffer[i][0]);
 223                 //g_debug("\t\tz1:    %f", (float)buffer[i][1]/0x7fffffff);
 224                 //g_debug("\t\tz2:    %f", (float)buffer[i][2]/0x7fffffff);
 225                 //g_debug("\t\tname:  %p", (gpointer)buffer[i][3]);
 226                 guint        index  = buffer[i][3];
 227                 GritsObject *object = objects->pdata[index];
 228                 object->state.picked = TRUE;
 229         }
 230
 231         /* Notify objects of pointer movements */
 232         for (guint i = 0; i < objects->len; i++) {
 233                 GritsObject *object = objects->pdata[i];
 234                 grits_object_set_pointer(object, object->state.picked);
 235         }
 236
 237         return hits;
 238 }
 239
 240 static gboolean on_motion_notify(GritsOpenGL *opengl, GdkEventMotion *event, gpointer _)
 241 {
 242         gdouble height = GTK_WIDGET(opengl)->allocation.height;
 243         gdouble gl_x   = event->x;
 244         gdouble gl_y   = height - event->y;
 245         gdouble delta  = opengl->pickmode ? 200 : 2;
 246
 247         if (opengl->pickmode) {
 248                 gtk_gl_begin(GTK_WIDGET(opengl));
 249                 glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 250         }
 251
 252         /* Save matricies */
 253         gdouble projection[16];
 254         gint    viewport[4]; // x=0,y=0,w,h
 255         glGetDoublev(GL_PROJECTION_MATRIX, projection);
 256         glGetIntegerv(GL_VIEWPORT, viewport);
 257         glMatrixMode(GL_MODELVIEW);  glPushMatrix();
 258         glMatrixMode(GL_PROJECTION); glPushMatrix();
 259
 260         g_mutex_lock(opengl->objects_lock);
 261
 262         GPtrArray *ortho = _objects_to_array(opengl, TRUE);
 263         GPtrArray *world = _objects_to_array(opengl, FALSE);
 264
 265         /* Run perspective picking */
 266         glMatrixMode(GL_PROJECTION); glLoadIdentity();
 267         gluPickMatrix(gl_x, gl_y, delta, delta, viewport);
 268         glMultMatrixd(projection);
 269         gint world_hits = run_picking(opengl, world);
 270
 271         /* Run ortho picking */
 272         glMatrixMode(GL_PROJECTION); glLoadIdentity();
 273         gluPickMatrix(gl_x, gl_y, delta, delta, viewport);
 274         glMatrixMode(GL_MODELVIEW);  glLoadIdentity();
 275         glOrtho(0, viewport[2], viewport[3], 0, 1000, -1000);
 276         gint ortho_hits = run_picking(opengl, ortho);
 277
 278         g_debug("GritsOpenGL: on_motion_notify - hits=%d/%d,%d/%d ev=%.0lf,%.0lf",
 279                         world_hits, world->len, ortho_hits, ortho->len, gl_x, gl_y);
 280
 281         g_ptr_array_free(world, TRUE);
 282         g_ptr_array_free(ortho, TRUE);
 283
 284         g_mutex_unlock(opengl->objects_lock);
 285
 286
 287         /* Test unproject */
 288         //gdouble lat, lon, elev;
 289         //grits_viewer_unproject(GRITS_VIEWER(opengl),
 290         //              gl_x, gl_y, -1, &lat, &lon, &elev);
 291
 292         /* Cleanup */
 293         glMatrixMode(GL_PROJECTION); glPopMatrix();
 294         glMatrixMode(GL_MODELVIEW);  glPopMatrix();
 295
 296         if (opengl->pickmode)
 297                 gtk_gl_end(GTK_WIDGET(opengl));
 298
 299         return FALSE;
 300 }
 301
 302 static gboolean _draw_level(gpointer key, gpointer value, gpointer user_data)
 303 {
 304         GritsOpenGL *opengl = user_data;
 305         glong lnum = (glong)key;
 306         struct RenderLevel *level = value;
 307
 308         g_debug("GritsOpenGL: _draw_level - level=%-4ld", lnum);
 309         int nsorted = 0, nunsorted = 0;
 310         GList *cur = NULL;
 311
 312         /* Configure individual levels */
 313         if (lnum < GRITS_LEVEL_WORLD) {
 314                 /* Disable depth for background levels */
 315                 glDepthMask(FALSE);
 316                 glDisable(GL_ALPHA_TEST);
 317         } else if (lnum < GRITS_LEVEL_OVERLAY) {
 318                 /* Enable depth and alpha for world levels */
 319                 glEnable(GL_ALPHA_TEST);
 320                 glAlphaFunc(GL_GREATER, 0.1);
 321                 glDepthMask(TRUE);
 322         } else {
 323                 /* Disable depth for Overlay/HUD levels */
 324                 // This causes rendering glitches not sure why..
 325                 //glDepthMask(FALSE);
 326         }
 327
 328         /* Start ortho */
 329         if (lnum >= GRITS_LEVEL_HUD) {
 330                 glMatrixMode(GL_PROJECTION); glPushMatrix(); glLoadIdentity();
 331                 glMatrixMode(GL_MODELVIEW);  glPushMatrix(); glLoadIdentity();
 332                 gint win_width  = GTK_WIDGET(opengl)->allocation.width;
 333                 gint win_height = GTK_WIDGET(opengl)->allocation.height;
 334                 glOrtho(0, win_width, win_height, 0, 1000, -1000);
 335         }
 336
 337         /* Draw unsorted objects without depth testing,
 338          * these are polygons, etc, rather than physical objects */
 339         glDisable(GL_DEPTH_TEST);
 340         for (cur = level->unsorted.next; cur; cur = cur->next, nunsorted++)
 341                 grits_object_draw(GRITS_OBJECT(cur->data), opengl);
 342
 343         /* Draw sorted objects using depth testing
 344          * These are things that are actually part of the world */
 345         glEnable(GL_DEPTH_TEST);
 346         for (cur = level->sorted.next; cur; cur = cur->next, nsorted++)
 347                 grits_object_draw(GRITS_OBJECT(cur->data), opengl);
 348
 349         /* End ortho */
 350         if (lnum >= GRITS_LEVEL_HUD) {
 351                 glMatrixMode(GL_PROJECTION); glPopMatrix();
 352                 glMatrixMode(GL_MODELVIEW);  glPopMatrix();
 353         }
 354
 355         /* TODO: Prune empty levels */
 356
 357         g_debug("GritsOpenGL: _draw_level - drew %d,%d objects",
 358                         nunsorted, nsorted);
 359         return FALSE;
 360 }
 361
 362 static gboolean on_expose(GritsOpenGL *opengl, GdkEventExpose *event, gpointer _)
 363 {
 364         g_debug("GritsOpenGL: on_expose - begin");
 365
 366         if (opengl->pickmode)
 367                 return on_motion_notify(opengl, (GdkEventMotion*)event, NULL);
 368
 369         gtk_gl_begin(GTK_WIDGET(opengl));
 370
 371         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 372
 373         _set_visuals(opengl);
 374 #ifdef ROAM_DEBUG
 375         glColor4f(1.0, 1.0, 1.0, 1.0);
 376         glLineWidth(2);
 377         glDisable(GL_TEXTURE_2D);
 378         glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
 379         roam_sphere_draw(opengl->sphere);
 380         (void)_draw_level;
 381         //roam_sphere_draw_normals(opengl->sphere);
 382 #else
 383         g_mutex_lock(opengl->objects_lock);
 384         if (opengl->wireframe)
 385                 glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
 386         g_tree_foreach(opengl->objects, _draw_level, opengl);
 387         g_mutex_unlock(opengl->objects_lock);
 388 #endif
 389
 390         gtk_gl_end(GTK_WIDGET(opengl));
 391
 392         g_debug("GritsOpenGL: on_expose - end\n");
 393         return FALSE;
 394 }
 395
 396 static gboolean on_key_press(GritsOpenGL *opengl, GdkEventKey *event, gpointer _)
 397 {
 398         g_debug("GritsOpenGL: on_key_press - key=%x, state=%x, plus=%x",
 399                         event->keyval, event->state, GDK_plus);
 400
 401         guint kv = event->keyval;
 402         /* Testing */
 403         if (kv == GDK_w) {
 404                 opengl->wireframe = !opengl->wireframe;
 405                 gtk_widget_queue_draw(GTK_WIDGET(opengl));
 406         }
 407         if (kv == GDK_p) {
 408                 opengl->pickmode = !opengl->pickmode;
 409                 gtk_widget_queue_draw(GTK_WIDGET(opengl));
 410         }
 411 #ifdef ROAM_DEBUG
 412         else if (kv == GDK_n) roam_sphere_split_one(opengl->sphere);
 413         else if (kv == GDK_p) roam_sphere_merge_one(opengl->sphere);
 414         else if (kv == GDK_r) roam_sphere_split_merge(opengl->sphere);
 415         else if (kv == GDK_u) roam_sphere_update_errors(opengl->sphere);
 416         gtk_widget_queue_draw(GTK_WIDGET(opengl));
 417 #endif
 418         return FALSE;
 419 }
 420
 421 static gboolean on_chained_event(GritsOpenGL *opengl, GdkEvent *event, gpointer _)
 422 {
 423         _foreach_object(opengl, (GritsLevelFunc)grits_object_event, event);
 424         return FALSE;
 425 }
 426
 427 static gboolean _update_errors_cb(gpointer _opengl)
 428 {
 429         GritsOpenGL *opengl = _opengl;
 430         g_mutex_lock(opengl->sphere_lock);
 431         roam_sphere_update_errors(opengl->sphere);
 432         g_mutex_unlock(opengl->sphere_lock);
 433         opengl->ue_source = 0;
 434         return FALSE;
 435 }
 436 static void on_view_changed(GritsOpenGL *opengl,
 437                 gdouble _1, gdouble _2, gdouble _3)
 438 {
 439         g_debug("GritsOpenGL: on_view_changed");
 440         _set_visuals(opengl);
 441 #ifndef ROAM_DEBUG
 442         if (!opengl->ue_source)
 443                 opengl->ue_source = g_idle_add_full(G_PRIORITY_HIGH_IDLE+30,
 444                                 _update_errors_cb, opengl, NULL);
 445         //roam_sphere_update_errors(opengl->sphere);
 446 #else
 447         (void)_update_errors_cb;
 448 #endif
 449 }
 450
 451 static gboolean on_idle(GritsOpenGL *opengl)
 452 {
 453         //g_debug("GritsOpenGL: on_idle");
 454         g_mutex_lock(opengl->sphere_lock);
 455         if (roam_sphere_split_merge(opengl->sphere))
 456                 gtk_widget_queue_draw(GTK_WIDGET(opengl));
 457         g_mutex_unlock(opengl->sphere_lock);
 458         return TRUE;
 459 }
 460
 461 static void on_realize(GritsOpenGL *opengl, gpointer _)
 462 {
 463         g_debug("GritsOpenGL: on_realize");
 464         gtk_gl_begin(GTK_WIDGET(opengl));
 465
 466         /* Connect signals and idle functions now that opengl is fully initialized */
 467         gtk_widget_add_events(GTK_WIDGET(opengl), GDK_KEY_PRESS_MASK);
 468         g_signal_connect(opengl, "configure-event",  G_CALLBACK(on_configure),    NULL);
 469         g_signal_connect(opengl, "expose-event",     G_CALLBACK(on_expose),       NULL);
 470
 471         g_signal_connect(opengl, "key-press-event",  G_CALLBACK(on_key_press),    NULL);
 472
 473         g_signal_connect(opengl, "location-changed", G_CALLBACK(on_view_changed), NULL);
 474         g_signal_connect(opengl, "rotation-changed", G_CALLBACK(on_view_changed), NULL);
 475
 476         g_signal_connect(opengl, "motion-notify-event", G_CALLBACK(on_motion_notify), NULL);
 477         g_signal_connect_after(opengl, "key-press-event",      G_CALLBACK(on_chained_event), NULL);
 478         g_signal_connect_after(opengl, "key-release-event",    G_CALLBACK(on_chained_event), NULL);
 479         g_signal_connect_after(opengl, "button-press-event",   G_CALLBACK(on_chained_event), NULL);
 480         g_signal_connect_after(opengl, "button-release-event", G_CALLBACK(on_chained_event), NULL);
 481         g_signal_connect_after(opengl, "motion-notify-event",  G_CALLBACK(on_chained_event), NULL);
 482
 483 #ifndef ROAM_DEBUG
 484         opengl->sm_source[0] = g_timeout_add_full(G_PRIORITY_HIGH_IDLE+30, 33,  (GSourceFunc)on_idle, opengl, NULL);
 485         opengl->sm_source[1] = g_timeout_add_full(G_PRIORITY_HIGH_IDLE+10, 500, (GSourceFunc)on_idle, opengl, NULL);
 486 #else
 487         (void)on_idle;
 488         (void)_update_errors_cb;
 489 #endif
 490
 491         /* Re-queue resize incase configure was triggered before realize */
 492         gtk_widget_queue_resize(GTK_WIDGET(opengl));
 493 }
 494
 495 /*********************
 496  * GritsViewer methods *
 497  *********************/
 498 /**
 499  * grits_opengl_new:
 500  * @plugins: the plugins store to use
 501  * @prefs:   the preferences object to use
 502  *
 503  * Create a new OpenGL renderer.
 504  *
 505  * Returns: the new #GritsOpenGL
 506  */
 507 GritsViewer *grits_opengl_new(GritsPlugins *plugins, GritsPrefs *prefs)
 508 {
 509         g_debug("GritsOpenGL: new");
 510         GritsViewer *opengl = g_object_new(GRITS_TYPE_OPENGL, NULL);
 511         grits_viewer_setup(opengl, plugins, prefs);
 512         return opengl;
 513 }
 514
 515 static void grits_opengl_center_position(GritsViewer *_opengl, gdouble lat, gdouble lon, gdouble elev)
 516 {
 517         glRotatef(lon, 0, 1, 0);
 518         glRotatef(-lat, 1, 0, 0);
 519         glTranslatef(0, 0, elev2rad(elev));
 520 }
 521
 522 static void grits_opengl_project(GritsViewer *_opengl,
 523                 gdouble lat, gdouble lon, gdouble elev,
 524                 gdouble *px, gdouble *py, gdouble *pz)
 525 {
 526         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 527         gdouble x, y, z;
 528         lle2xyz(lat, lon, elev, &x, &y, &z);
 529         gluProject(x, y, z,
 530                 opengl->sphere->view->model,
 531                 opengl->sphere->view->proj,
 532                 opengl->sphere->view->view,
 533                 px, py, pz);
 534 }
 535
 536 static void grits_opengl_unproject(GritsViewer *_opengl,
 537                 gdouble px, gdouble py, gdouble pz,
 538                 gdouble *lat, gdouble *lon, gdouble *elev)
 539 {
 540         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 541         if (!opengl->sphere->view)
 542                 return;
 543         gdouble x, y, z;
 544         if (pz < 0) {
 545                 gfloat tmp = 0;
 546                 glReadPixels(px, py, 1, 1, GL_DEPTH_COMPONENT, GL_FLOAT, &tmp);
 547                 pz = tmp;
 548         }
 549         gluUnProject(px, py, pz,
 550                 opengl->sphere->view->model,
 551                 opengl->sphere->view->proj,
 552                 opengl->sphere->view->view,
 553                 &x, &y, &z);
 554         xyz2lle(x, y, z, lat, lon, elev);
 555         //g_message("GritsOpenGL: unproject - "
 556         //              "%4.0lf,%4.0lf,(%5.3lf) -> "
 557         //              "%8.0lf,%8.0lf,%8.0lf -> "
 558         //              "%6.2lf,%7.2lf,%4.0lf",
 559         //      px, py, pz, x, y, z, *lat, *lon, *elev);
 560 }
 561
 562 static void grits_opengl_set_height_func(GritsViewer *_opengl, GritsBounds *bounds,
 563                 RoamHeightFunc height_func, gpointer user_data, gboolean update)
 564 {
 565         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 566         /* TODO: get points? */
 567         g_mutex_lock(opengl->sphere_lock);
 568         GList *triangles = roam_sphere_get_intersect(opengl->sphere, TRUE,
 569                         bounds->n, bounds->s, bounds->e, bounds->w);
 570         for (GList *cur = triangles; cur; cur = cur->next) {
 571                 RoamTriangle *tri = cur->data;
 572                 RoamPoint *points[] = {tri->p.l, tri->p.m, tri->p.r, tri->split};
 573                 for (int i = 0; i < G_N_ELEMENTS(points); i++) {
 574                         if (bounds->n >= points[i]->lat && points[i]->lat >= bounds->s &&
 575                             bounds->e >= points[i]->lon && points[i]->lon >= bounds->w) {
 576                                 points[i]->height_func = height_func;
 577                                 points[i]->height_data = user_data;
 578                                 roam_point_update_height(points[i]);
 579                         }
 580                 }
 581         }
 582         g_list_free(triangles);
 583         g_mutex_unlock(opengl->sphere_lock);
 584 }
 585
 586 static void _grits_opengl_clear_height_func_rec(RoamTriangle *root)
 587 {
 588         if (!root)
 589                 return;
 590         RoamPoint *points[] = {root->p.l, root->p.m, root->p.r, root->split};
 591         for (int i = 0; i < G_N_ELEMENTS(points); i++) {
 592                 points[i]->height_func = NULL;
 593                 points[i]->height_data = NULL;
 594                 roam_point_update_height(points[i]);
 595         }
 596         _grits_opengl_clear_height_func_rec(root->kids[0]);
 597         _grits_opengl_clear_height_func_rec(root->kids[1]);
 598 }
 599
 600 static void grits_opengl_clear_height_func(GritsViewer *_opengl)
 601 {
 602         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 603         for (int i = 0; i < G_N_ELEMENTS(opengl->sphere->roots); i++)
 604                 _grits_opengl_clear_height_func_rec(opengl->sphere->roots[i]);
 605 }
 606
 607 static gpointer grits_opengl_add(GritsViewer *_opengl, GritsObject *object,
 608                 gint key, gboolean sort)
 609 {
 610         g_assert(GRITS_IS_OPENGL(_opengl));
 611         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 612         g_mutex_lock(opengl->objects_lock);
 613         struct RenderLevel *level = g_tree_lookup(opengl->objects, (gpointer)(gintptr)key);
 614         if (!level) {
 615                 level = g_new0(struct RenderLevel, 1);
 616                 g_tree_insert(opengl->objects, (gpointer)(gintptr)key, level);
 617         }
 618         GList *list = sort ? &level->sorted : &level->unsorted;
 619         /* Put the link in the list */
 620         GList *link = g_new0(GList, 1);
 621         link->data = object;
 622         link->prev = list;
 623         link->next = list->next;
 624         if (list->next)
 625                 list->next->prev = link;
 626         list->next = link;
 627         g_mutex_unlock(opengl->objects_lock);
 628         return link;
 629 }
 630
 631 static GritsObject *grits_opengl_remove(GritsViewer *_opengl, GritsObject *object)
 632 {
 633         g_assert(GRITS_IS_OPENGL(_opengl));
 634         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 635         GList *link = object->ref;
 636         g_mutex_lock(opengl->objects_lock);
 637         /* Just unlink and free it, link->prev is assured */
 638         link->prev->next = link->next;
 639         if (link->next)
 640                 link->next->prev = link->prev;
 641         g_mutex_unlock(opengl->objects_lock);
 642         object->ref    = NULL;
 643         object->viewer = NULL;
 644         g_free(link);
 645         g_object_unref(object);
 646         return object;
 647 }
 648
 649 /****************
 650  * GObject code *
 651  ****************/
 652 static int _objects_cmp(gconstpointer _a, gconstpointer _b, gpointer _)
 653 {
 654         gintptr a = (gintptr)_a, b = (gintptr)_b;
 655         return a < b ? -1 :
 656                a > b ?  1 : 0;
 657 }
 658 static void _objects_free(gpointer value)
 659 {
 660         struct RenderLevel *level = value;
 661         if (level->sorted.next)
 662                 g_list_free(level->sorted.next);
 663         if (level->unsorted.next)
 664                 g_list_free(level->unsorted.next);
 665         g_free(level);
 666 }
 667
 668 G_DEFINE_TYPE(GritsOpenGL, grits_opengl, GRITS_TYPE_VIEWER);
 669 static void grits_opengl_init(GritsOpenGL *opengl)
 670 {
 671         g_debug("GritsOpenGL: init");
 672         opengl->objects      = g_tree_new_full(_objects_cmp, NULL, NULL, _objects_free);
 673         opengl->objects_lock = g_mutex_new();
 674         opengl->sphere       = roam_sphere_new(opengl);
 675         opengl->sphere_lock  = g_mutex_new();
 676         gtk_gl_enable(GTK_WIDGET(opengl));
 677         gtk_widget_add_events(GTK_WIDGET(opengl), GDK_KEY_PRESS_MASK);
 678         g_signal_connect(opengl, "map", G_CALLBACK(on_realize), NULL);
 679 }
 680 static void grits_opengl_dispose(GObject *_opengl)
 681 {
 682         g_debug("GritsOpenGL: dispose");
 683         GritsOpenGL *opengl = GRITS_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(grits_opengl_parent_class)->dispose(_opengl);
 697 }
 698 static void grits_opengl_finalize(GObject *_opengl)
 699 {
 700         g_debug("GritsOpenGL: finalize");
 701         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 702         roam_sphere_free(opengl->sphere);
 703         g_tree_destroy(opengl->objects);
 704         g_mutex_free(opengl->objects_lock);
 705         g_mutex_free(opengl->sphere_lock);
 706         G_OBJECT_CLASS(grits_opengl_parent_class)->finalize(_opengl);
 707 }
 708 static void grits_opengl_class_init(GritsOpenGLClass *klass)
 709 {
 710         g_debug("GritsOpenGL: class_init");
 711         GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
 712         gobject_class->finalize = grits_opengl_finalize;
 713         gobject_class->dispose = grits_opengl_dispose;
 714
 715         GritsViewerClass *viewer_class = GRITS_VIEWER_CLASS(klass);
 716         viewer_class->center_position   = grits_opengl_center_position;
 717         viewer_class->project           = grits_opengl_project;
 718         viewer_class->unproject         = grits_opengl_unproject;
 719         viewer_class->clear_height_func = grits_opengl_clear_height_func;
 720         viewer_class->set_height_func   = grits_opengl_set_height_func;
 721         viewer_class->add               = grits_opengl_add;
 722         viewer_class->remove            = grits_opengl_remove;
 723 }