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 gboolean (*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                 if (user_func(cur->data, user_data, (gint)key, FALSE))
 151                         return TRUE;
 152         for (GList *cur = level->sorted.next;   cur; cur = cur->next)
 153                 if (user_func(cur->data, user_data, (gint)key, TRUE))
 154                         return TRUE;
 155         return FALSE;
 156 }
 157
 158 static void _foreach_object(GritsOpenGL *opengl, GritsLevelFunc func, gpointer user_data)
 159 {
 160         gpointer pointers[2] = {func, user_data};
 161         g_tree_foreach(opengl->objects, _foreach_object_cb, pointers);
 162 }
 163
 164 static gboolean _add_object_world(GritsObject *object, GPtrArray *array, gint level, gboolean sorted)
 165 {
 166         if (level < GRITS_LEVEL_HUD)
 167                 g_ptr_array_add(array, object);
 168         return FALSE;
 169 }
 170
 171 static gboolean _add_object_ortho(GritsObject *object, GPtrArray *array, gint level, gboolean sorted)
 172 {
 173         if (level >= GRITS_LEVEL_HUD)
 174                 g_ptr_array_add(array, object);
 175         return FALSE;
 176 }
 177
 178 static GPtrArray *_objects_to_array(GritsOpenGL *opengl, gboolean ortho)
 179 {
 180         GPtrArray *array = g_ptr_array_new();
 181         GritsLevelFunc func = (GritsLevelFunc)(ortho ? _add_object_ortho : _add_object_world);
 182         _foreach_object(opengl, func, array);
 183         return array;
 184 }
 185
 186 /*************
 187  * Callbacks *
 188  *************/
 189 static gboolean on_configure(GritsOpenGL *opengl, GdkEventConfigure *event, gpointer _)
 190 {
 191         g_debug("GritsOpenGL: on_configure");
 192
 193         _set_visuals(opengl);
 194 #ifndef ROAM_DEBUG
 195         g_mutex_lock(opengl->sphere_lock);
 196         roam_sphere_update_errors(opengl->sphere);
 197         g_mutex_unlock(opengl->sphere_lock);
 198 #endif
 199
 200         return FALSE;
 201 }
 202
 203 static gint run_picking(GritsOpenGL *opengl, GdkEvent *event, GPtrArray *objects)
 204 {
 205         /* Setup picking buffers */
 206         guint buffer[100][4] = {};
 207         glSelectBuffer(G_N_ELEMENTS(buffer), (guint*)buffer);
 208         if (!opengl->pickmode)
 209                 glRenderMode(GL_SELECT);
 210         glInitNames();
 211
 212         /* Render/pick objects */
 213         for (guint i = 0; i < objects->len; i++) {
 214                 glPushName(i);
 215                 GritsObject *object = objects->pdata[i];
 216                 object->state.picked = FALSE;
 217                 grits_object_pick(object, opengl);
 218                 glPopName();
 219         }
 220
 221         int hits = glRenderMode(GL_RENDER);
 222
 223         /* Process hits */
 224         for (int i = 0; i < hits; i++) {
 225                 //g_debug("\tHit: %d",     i);
 226                 //g_debug("\t\tcount: %d", buffer[i][0]);
 227                 //g_debug("\t\tz1:    %f", (float)buffer[i][1]/0x7fffffff);
 228                 //g_debug("\t\tz2:    %f", (float)buffer[i][2]/0x7fffffff);
 229                 //g_debug("\t\tname:  %p", (gpointer)buffer[i][3]);
 230                 guint        index  = buffer[i][3];
 231                 GritsObject *object = objects->pdata[index];
 232                 object->state.picked = TRUE;
 233         }
 234
 235         /* Notify objects of pointer movements */
 236         for (guint i = 0; i < objects->len; i++) {
 237                 GritsObject *object = objects->pdata[i];
 238                 grits_object_set_pointer(object, event, object->state.picked);
 239         }
 240
 241         return hits;
 242 }
 243
 244 static gboolean on_motion_notify(GritsOpenGL *opengl, GdkEventMotion *event, gpointer _)
 245 {
 246         gdouble height = GTK_WIDGET(opengl)->allocation.height;
 247         gdouble gl_x   = event->x;
 248         gdouble gl_y   = height - event->y;
 249         gdouble delta  = opengl->pickmode ? 200 : 2;
 250
 251         if (opengl->pickmode) {
 252                 gtk_gl_begin(GTK_WIDGET(opengl));
 253                 glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 254         }
 255
 256         /* Save matricies */
 257         gdouble projection[16];
 258         gint    viewport[4]; // x=0,y=0,w,h
 259         glGetDoublev(GL_PROJECTION_MATRIX, projection);
 260         glGetIntegerv(GL_VIEWPORT, viewport);
 261         glMatrixMode(GL_MODELVIEW);  glPushMatrix();
 262         glMatrixMode(GL_PROJECTION); glPushMatrix();
 263
 264         g_mutex_lock(opengl->objects_lock);
 265
 266         GPtrArray *ortho = _objects_to_array(opengl, TRUE);
 267         GPtrArray *world = _objects_to_array(opengl, FALSE);
 268
 269         /* Run perspective picking */
 270         glMatrixMode(GL_PROJECTION); glLoadIdentity();
 271         gluPickMatrix(gl_x, gl_y, delta, delta, viewport);
 272         glMultMatrixd(projection);
 273         gint world_hits = run_picking(opengl, (GdkEvent*)event, world);
 274
 275         /* Run ortho picking */
 276         glMatrixMode(GL_PROJECTION); glLoadIdentity();
 277         gluPickMatrix(gl_x, gl_y, delta, delta, viewport);
 278         glMatrixMode(GL_MODELVIEW);  glLoadIdentity();
 279         glOrtho(0, viewport[2], viewport[3], 0, 1000, -1000);
 280         gint ortho_hits = run_picking(opengl, (GdkEvent*)event, ortho);
 281
 282         g_debug("GritsOpenGL: on_motion_notify - hits=%d/%d,%d/%d ev=%.0lf,%.0lf",
 283                         world_hits, world->len, ortho_hits, ortho->len, gl_x, gl_y);
 284
 285         g_ptr_array_free(world, TRUE);
 286         g_ptr_array_free(ortho, TRUE);
 287
 288         g_mutex_unlock(opengl->objects_lock);
 289
 290
 291         /* Test unproject */
 292         //gdouble lat, lon, elev;
 293         //grits_viewer_unproject(GRITS_VIEWER(opengl),
 294         //              gl_x, gl_y, -1, &lat, &lon, &elev);
 295
 296         /* Cleanup */
 297         glMatrixMode(GL_PROJECTION); glPopMatrix();
 298         glMatrixMode(GL_MODELVIEW);  glPopMatrix();
 299
 300         if (opengl->pickmode)
 301                 gtk_gl_end(GTK_WIDGET(opengl));
 302
 303         return FALSE;
 304 }
 305
 306 static gboolean _draw_level(gpointer key, gpointer value, gpointer user_data)
 307 {
 308         GritsOpenGL *opengl = user_data;
 309         glong lnum = (glong)key;
 310         struct RenderLevel *level = value;
 311
 312         g_debug("GritsOpenGL: _draw_level - level=%-4ld", lnum);
 313         int nsorted = 0, nunsorted = 0;
 314         GList *cur = NULL;
 315
 316         /* Configure individual levels */
 317         if (lnum < GRITS_LEVEL_WORLD) {
 318                 /* Disable depth for background levels */
 319                 glDepthMask(FALSE);
 320                 glDisable(GL_ALPHA_TEST);
 321         } else if (lnum < GRITS_LEVEL_OVERLAY) {
 322                 /* Enable depth and alpha for world levels */
 323                 glEnable(GL_ALPHA_TEST);
 324                 glAlphaFunc(GL_GREATER, 0.1);
 325                 glDepthMask(TRUE);
 326         } else {
 327                 /* Disable depth for Overlay/HUD levels */
 328                 // This causes rendering glitches not sure why..
 329                 //glDepthMask(FALSE);
 330         }
 331
 332         /* Start ortho */
 333         if (lnum >= GRITS_LEVEL_HUD) {
 334                 glMatrixMode(GL_PROJECTION); glPushMatrix(); glLoadIdentity();
 335                 glMatrixMode(GL_MODELVIEW);  glPushMatrix(); glLoadIdentity();
 336                 gint win_width  = GTK_WIDGET(opengl)->allocation.width;
 337                 gint win_height = GTK_WIDGET(opengl)->allocation.height;
 338                 glOrtho(0, win_width, win_height, 0, 1000, -1000);
 339         }
 340
 341         /* Draw unsorted objects without depth testing,
 342          * these are polygons, etc, rather than physical objects */
 343         glDisable(GL_DEPTH_TEST);
 344         for (cur = level->unsorted.next; cur; cur = cur->next, nunsorted++)
 345                 grits_object_draw(GRITS_OBJECT(cur->data), opengl);
 346
 347         /* Draw sorted objects using depth testing
 348          * These are things that are actually part of the world */
 349         glEnable(GL_DEPTH_TEST);
 350         for (cur = level->sorted.next; cur; cur = cur->next, nsorted++)
 351                 grits_object_draw(GRITS_OBJECT(cur->data), opengl);
 352
 353         /* End ortho */
 354         if (lnum >= GRITS_LEVEL_HUD) {
 355                 glMatrixMode(GL_PROJECTION); glPopMatrix();
 356                 glMatrixMode(GL_MODELVIEW);  glPopMatrix();
 357         }
 358
 359         /* TODO: Prune empty levels */
 360
 361         g_debug("GritsOpenGL: _draw_level - drew %d,%d objects",
 362                         nunsorted, nsorted);
 363         return FALSE;
 364 }
 365
 366 static gboolean on_expose(GritsOpenGL *opengl, GdkEventExpose *event, gpointer _)
 367 {
 368         g_debug("GritsOpenGL: on_expose - begin");
 369
 370         if (opengl->pickmode)
 371                 return on_motion_notify(opengl, (GdkEventMotion*)event, NULL);
 372
 373         gtk_gl_begin(GTK_WIDGET(opengl));
 374
 375         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 376
 377         _set_visuals(opengl);
 378 #ifdef ROAM_DEBUG
 379         glColor4f(1.0, 1.0, 1.0, 1.0);
 380         glLineWidth(2);
 381         glDisable(GL_TEXTURE_2D);
 382         glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
 383         roam_sphere_draw(opengl->sphere);
 384         (void)_draw_level;
 385         //roam_sphere_draw_normals(opengl->sphere);
 386 #else
 387         g_mutex_lock(opengl->objects_lock);
 388         if (opengl->wireframe)
 389                 glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
 390         g_tree_foreach(opengl->objects, _draw_level, opengl);
 391         g_mutex_unlock(opengl->objects_lock);
 392 #endif
 393
 394         gtk_gl_end(GTK_WIDGET(opengl));
 395
 396         g_debug("GritsOpenGL: on_expose - end\n");
 397         return FALSE;
 398 }
 399
 400 static gboolean on_key_press(GritsOpenGL *opengl, GdkEventKey *event, gpointer _)
 401 {
 402         g_debug("GritsOpenGL: on_key_press - key=%x, state=%x, plus=%x",
 403                         event->keyval, event->state, GDK_plus);
 404
 405         guint kv = event->keyval;
 406         /* Testing */
 407         if (kv == GDK_w) {
 408                 opengl->wireframe = !opengl->wireframe;
 409                 gtk_widget_queue_draw(GTK_WIDGET(opengl));
 410         }
 411         if (kv == GDK_p) {
 412                 opengl->pickmode = !opengl->pickmode;
 413                 gtk_widget_queue_draw(GTK_WIDGET(opengl));
 414         }
 415 #ifdef ROAM_DEBUG
 416         else if (kv == GDK_n) roam_sphere_split_one(opengl->sphere);
 417         else if (kv == GDK_p) roam_sphere_merge_one(opengl->sphere);
 418         else if (kv == GDK_r) roam_sphere_split_merge(opengl->sphere);
 419         else if (kv == GDK_u) roam_sphere_update_errors(opengl->sphere);
 420         gtk_widget_queue_draw(GTK_WIDGET(opengl));
 421 #endif
 422         return FALSE;
 423 }
 424
 425 static gboolean on_chained_event(GritsOpenGL *opengl, GdkEvent *event, gpointer _)
 426 {
 427         _foreach_object(opengl, (GritsLevelFunc)grits_object_event, event);
 428         return FALSE;
 429 }
 430
 431 static gboolean _update_errors_cb(gpointer _opengl)
 432 {
 433         GritsOpenGL *opengl = _opengl;
 434         g_mutex_lock(opengl->sphere_lock);
 435         roam_sphere_update_errors(opengl->sphere);
 436         g_mutex_unlock(opengl->sphere_lock);
 437         opengl->ue_source = 0;
 438         return FALSE;
 439 }
 440 static void on_view_changed(GritsOpenGL *opengl,
 441                 gdouble _1, gdouble _2, gdouble _3)
 442 {
 443         g_debug("GritsOpenGL: on_view_changed");
 444         _set_visuals(opengl);
 445 #ifndef ROAM_DEBUG
 446         if (!opengl->ue_source)
 447                 opengl->ue_source = g_idle_add_full(G_PRIORITY_HIGH_IDLE+30,
 448                                 _update_errors_cb, opengl, NULL);
 449         //roam_sphere_update_errors(opengl->sphere);
 450 #else
 451         (void)_update_errors_cb;
 452 #endif
 453 }
 454
 455 static gboolean on_idle(GritsOpenGL *opengl)
 456 {
 457         //g_debug("GritsOpenGL: on_idle");
 458         g_mutex_lock(opengl->sphere_lock);
 459         if (roam_sphere_split_merge(opengl->sphere))
 460                 gtk_widget_queue_draw(GTK_WIDGET(opengl));
 461         g_mutex_unlock(opengl->sphere_lock);
 462         return TRUE;
 463 }
 464
 465 static void on_realize(GritsOpenGL *opengl, gpointer _)
 466 {
 467         g_debug("GritsOpenGL: on_realize");
 468         gtk_gl_begin(GTK_WIDGET(opengl));
 469
 470         /* Connect signals and idle functions now that opengl is fully initialized */
 471         gtk_widget_add_events(GTK_WIDGET(opengl), GDK_KEY_PRESS_MASK);
 472         g_signal_connect(opengl, "configure-event",  G_CALLBACK(on_configure),    NULL);
 473         g_signal_connect(opengl, "expose-event",     G_CALLBACK(on_expose),       NULL);
 474
 475         g_signal_connect(opengl, "key-press-event",  G_CALLBACK(on_key_press),    NULL);
 476
 477         g_signal_connect(opengl, "location-changed", G_CALLBACK(on_view_changed), NULL);
 478         g_signal_connect(opengl, "rotation-changed", G_CALLBACK(on_view_changed), NULL);
 479
 480         g_signal_connect(opengl, "motion-notify-event", G_CALLBACK(on_motion_notify), NULL);
 481         g_signal_connect_after(opengl, "key-press-event",      G_CALLBACK(on_chained_event), NULL);
 482         g_signal_connect_after(opengl, "key-release-event",    G_CALLBACK(on_chained_event), NULL);
 483         g_signal_connect_after(opengl, "button-press-event",   G_CALLBACK(on_chained_event), NULL);
 484         g_signal_connect_after(opengl, "button-release-event", G_CALLBACK(on_chained_event), NULL);
 485         g_signal_connect_after(opengl, "motion-notify-event",  G_CALLBACK(on_chained_event), NULL);
 486
 487 #ifndef ROAM_DEBUG
 488         opengl->sm_source[0] = g_timeout_add_full(G_PRIORITY_HIGH_IDLE+30, 33,  (GSourceFunc)on_idle, opengl, NULL);
 489         opengl->sm_source[1] = g_timeout_add_full(G_PRIORITY_HIGH_IDLE+10, 500, (GSourceFunc)on_idle, opengl, NULL);
 490 #else
 491         (void)on_idle;
 492         (void)_update_errors_cb;
 493 #endif
 494
 495         /* Re-queue resize incase configure was triggered before realize */
 496         gtk_widget_queue_resize(GTK_WIDGET(opengl));
 497 }
 498
 499 /*********************
 500  * GritsViewer methods *
 501  *********************/
 502 /**
 503  * grits_opengl_new:
 504  * @plugins: the plugins store to use
 505  * @prefs:   the preferences object to use
 506  *
 507  * Create a new OpenGL renderer.
 508  *
 509  * Returns: the new #GritsOpenGL
 510  */
 511 GritsViewer *grits_opengl_new(GritsPlugins *plugins, GritsPrefs *prefs)
 512 {
 513         g_debug("GritsOpenGL: new");
 514         GritsViewer *opengl = g_object_new(GRITS_TYPE_OPENGL, NULL);
 515         grits_viewer_setup(opengl, plugins, prefs);
 516         return opengl;
 517 }
 518
 519 static void grits_opengl_center_position(GritsViewer *_opengl, gdouble lat, gdouble lon, gdouble elev)
 520 {
 521         glRotatef(lon, 0, 1, 0);
 522         glRotatef(-lat, 1, 0, 0);
 523         glTranslatef(0, 0, elev2rad(elev));
 524 }
 525
 526 static void grits_opengl_project(GritsViewer *_opengl,
 527                 gdouble lat, gdouble lon, gdouble elev,
 528                 gdouble *px, gdouble *py, gdouble *pz)
 529 {
 530         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 531         gdouble x, y, z;
 532         lle2xyz(lat, lon, elev, &x, &y, &z);
 533         gluProject(x, y, z,
 534                 opengl->sphere->view->model,
 535                 opengl->sphere->view->proj,
 536                 opengl->sphere->view->view,
 537                 px, py, pz);
 538 }
 539
 540 static void grits_opengl_unproject(GritsViewer *_opengl,
 541                 gdouble px, gdouble py, gdouble pz,
 542                 gdouble *lat, gdouble *lon, gdouble *elev)
 543 {
 544         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 545         if (!opengl->sphere->view)
 546                 return;
 547         gdouble x, y, z;
 548         if (pz < 0) {
 549                 gfloat tmp = 0;
 550                 glReadPixels(px, py, 1, 1, GL_DEPTH_COMPONENT, GL_FLOAT, &tmp);
 551                 pz = tmp;
 552         }
 553         gluUnProject(px, py, pz,
 554                 opengl->sphere->view->model,
 555                 opengl->sphere->view->proj,
 556                 opengl->sphere->view->view,
 557                 &x, &y, &z);
 558         xyz2lle(x, y, z, lat, lon, elev);
 559         //g_message("GritsOpenGL: unproject - "
 560         //              "%4.0lf,%4.0lf,(%5.3lf) -> "
 561         //              "%8.0lf,%8.0lf,%8.0lf -> "
 562         //              "%6.2lf,%7.2lf,%4.0lf",
 563         //      px, py, pz, x, y, z, *lat, *lon, *elev);
 564 }
 565
 566 static void grits_opengl_set_height_func(GritsViewer *_opengl, GritsBounds *bounds,
 567                 RoamHeightFunc height_func, gpointer user_data, gboolean update)
 568 {
 569         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 570         /* TODO: get points? */
 571         g_mutex_lock(opengl->sphere_lock);
 572         GList *triangles = roam_sphere_get_intersect(opengl->sphere, TRUE,
 573                         bounds->n, bounds->s, bounds->e, bounds->w);
 574         for (GList *cur = triangles; cur; cur = cur->next) {
 575                 RoamTriangle *tri = cur->data;
 576                 RoamPoint *points[] = {tri->p.l, tri->p.m, tri->p.r, tri->split};
 577                 for (int i = 0; i < G_N_ELEMENTS(points); i++) {
 578                         if (bounds->n >= points[i]->lat && points[i]->lat >= bounds->s &&
 579                             bounds->e >= points[i]->lon && points[i]->lon >= bounds->w) {
 580                                 points[i]->height_func = height_func;
 581                                 points[i]->height_data = user_data;
 582                                 roam_point_update_height(points[i]);
 583                         }
 584                 }
 585         }
 586         g_list_free(triangles);
 587         g_mutex_unlock(opengl->sphere_lock);
 588 }
 589
 590 static void _grits_opengl_clear_height_func_rec(RoamTriangle *root)
 591 {
 592         if (!root)
 593                 return;
 594         RoamPoint *points[] = {root->p.l, root->p.m, root->p.r, root->split};
 595         for (int i = 0; i < G_N_ELEMENTS(points); i++) {
 596                 points[i]->height_func = NULL;
 597                 points[i]->height_data = NULL;
 598                 roam_point_update_height(points[i]);
 599         }
 600         _grits_opengl_clear_height_func_rec(root->kids[0]);
 601         _grits_opengl_clear_height_func_rec(root->kids[1]);
 602 }
 603
 604 static void grits_opengl_clear_height_func(GritsViewer *_opengl)
 605 {
 606         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 607         for (int i = 0; i < G_N_ELEMENTS(opengl->sphere->roots); i++)
 608                 _grits_opengl_clear_height_func_rec(opengl->sphere->roots[i]);
 609 }
 610
 611 static gpointer grits_opengl_add(GritsViewer *_opengl, GritsObject *object,
 612                 gint key, gboolean sort)
 613 {
 614         g_assert(GRITS_IS_OPENGL(_opengl));
 615         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 616         g_mutex_lock(opengl->objects_lock);
 617         struct RenderLevel *level = g_tree_lookup(opengl->objects, (gpointer)(gintptr)key);
 618         if (!level) {
 619                 level = g_new0(struct RenderLevel, 1);
 620                 g_tree_insert(opengl->objects, (gpointer)(gintptr)key, level);
 621         }
 622         GList *list = sort ? &level->sorted : &level->unsorted;
 623         /* Put the link in the list */
 624         GList *link = g_new0(GList, 1);
 625         link->data = object;
 626         link->prev = list;
 627         link->next = list->next;
 628         if (list->next)
 629                 list->next->prev = link;
 630         list->next = link;
 631         g_mutex_unlock(opengl->objects_lock);
 632         return link;
 633 }
 634
 635 static GritsObject *grits_opengl_remove(GritsViewer *_opengl, GritsObject *object)
 636 {
 637         g_assert(GRITS_IS_OPENGL(_opengl));
 638         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 639         GList *link = object->ref;
 640         g_mutex_lock(opengl->objects_lock);
 641         /* Just unlink and free it, link->prev is assured */
 642         link->prev->next = link->next;
 643         if (link->next)
 644                 link->next->prev = link->prev;
 645         g_mutex_unlock(opengl->objects_lock);
 646         object->ref    = NULL;
 647         object->viewer = NULL;
 648         g_free(link);
 649         g_object_unref(object);
 650         return object;
 651 }
 652
 653 /****************
 654  * GObject code *
 655  ****************/
 656 static int _objects_cmp(gconstpointer _a, gconstpointer _b, gpointer _)
 657 {
 658         gintptr a = (gintptr)_a, b = (gintptr)_b;
 659         return a < b ? -1 :
 660                a > b ?  1 : 0;
 661 }
 662 static void _objects_free(gpointer value)
 663 {
 664         struct RenderLevel *level = value;
 665         if (level->sorted.next)
 666                 g_list_free(level->sorted.next);
 667         if (level->unsorted.next)
 668                 g_list_free(level->unsorted.next);
 669         g_free(level);
 670 }
 671
 672 G_DEFINE_TYPE(GritsOpenGL, grits_opengl, GRITS_TYPE_VIEWER);
 673 static void grits_opengl_init(GritsOpenGL *opengl)
 674 {
 675         g_debug("GritsOpenGL: init");
 676         opengl->objects      = g_tree_new_full(_objects_cmp, NULL, NULL, _objects_free);
 677         opengl->objects_lock = g_mutex_new();
 678         opengl->sphere       = roam_sphere_new(opengl);
 679         opengl->sphere_lock  = g_mutex_new();
 680         gtk_gl_enable(GTK_WIDGET(opengl));
 681         gtk_widget_add_events(GTK_WIDGET(opengl), GDK_KEY_PRESS_MASK);
 682         g_signal_connect(opengl, "map", G_CALLBACK(on_realize), NULL);
 683 }
 684 static void grits_opengl_dispose(GObject *_opengl)
 685 {
 686         g_debug("GritsOpenGL: dispose");
 687         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 688         if (opengl->sm_source[0]) {
 689                 g_source_remove(opengl->sm_source[0]);
 690                 opengl->sm_source[0] = 0;
 691         }
 692         if (opengl->sm_source[1]) {
 693                 g_source_remove(opengl->sm_source[1]);
 694                 opengl->sm_source[1] = 0;
 695         }
 696         if (opengl->ue_source) {
 697                 g_source_remove(opengl->ue_source);
 698                 opengl->ue_source = 0;
 699         }
 700         G_OBJECT_CLASS(grits_opengl_parent_class)->dispose(_opengl);
 701 }
 702 static void grits_opengl_finalize(GObject *_opengl)
 703 {
 704         g_debug("GritsOpenGL: finalize");
 705         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 706         roam_sphere_free(opengl->sphere);
 707         g_tree_destroy(opengl->objects);
 708         g_mutex_free(opengl->objects_lock);
 709         g_mutex_free(opengl->sphere_lock);
 710         G_OBJECT_CLASS(grits_opengl_parent_class)->finalize(_opengl);
 711 }
 712 static void grits_opengl_class_init(GritsOpenGLClass *klass)
 713 {
 714         g_debug("GritsOpenGL: class_init");
 715         GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
 716         gobject_class->finalize = grits_opengl_finalize;
 717         gobject_class->dispose = grits_opengl_dispose;
 718
 719         GritsViewerClass *viewer_class = GRITS_VIEWER_CLASS(klass);
 720         viewer_class->center_position   = grits_opengl_center_position;
 721         viewer_class->project           = grits_opengl_project;
 722         viewer_class->unproject         = grits_opengl_unproject;
 723         viewer_class->clear_height_func = grits_opengl_clear_height_func;
 724         viewer_class->set_height_func   = grits_opengl_set_height_func;
 725         viewer_class->add               = grits_opengl_add;
 726         viewer_class->remove            = grits_opengl_remove;
 727 }