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,
 204                 GPtrArray *objects, GritsObject **top)
 205 {
 206         /* Setup picking buffers */
 207         guint buffer[100][4] = {};
 208         glSelectBuffer(G_N_ELEMENTS(buffer), (guint*)buffer);
 209         if (!opengl->pickmode)
 210                 glRenderMode(GL_SELECT);
 211         glInitNames();
 212
 213         /* Render/pick objects */
 214         for (guint i = 0; i < objects->len; i++) {
 215                 glPushName(i);
 216                 GritsObject *object = objects->pdata[i];
 217                 object->state.picked = FALSE;
 218                 grits_object_pick(object, opengl);
 219                 glPopName();
 220         }
 221
 222         int hits = glRenderMode(GL_RENDER);
 223
 224         /* Process hits */
 225         for (int i = 0; i < hits; i++) {
 226                 //g_debug("\tHit: %d",     i);
 227                 //g_debug("\t\tcount: %d", buffer[i][0]);
 228                 //g_debug("\t\tz1:    %f", (float)buffer[i][1]/0x7fffffff);
 229                 //g_debug("\t\tz2:    %f", (float)buffer[i][2]/0x7fffffff);
 230                 //g_debug("\t\tname:  %p", (gpointer)buffer[i][3]);
 231                 guint        index  = buffer[i][3];
 232                 GritsObject *object = objects->pdata[index];
 233                 object->state.picked = TRUE;
 234                 *top = object;
 235         }
 236
 237         /* Notify objects of pointer movements */
 238         for (guint i = 0; i < objects->len; i++) {
 239                 GritsObject *object = objects->pdata[i];
 240                 grits_object_set_pointer(object, event, object->state.picked);
 241         }
 242
 243         return hits;
 244 }
 245
 246 static gboolean on_motion_notify(GritsOpenGL *opengl, GdkEventMotion *event, gpointer _)
 247 {
 248         gdouble height = GTK_WIDGET(opengl)->allocation.height;
 249         gdouble gl_x   = event->x;
 250         gdouble gl_y   = height - event->y;
 251         gdouble delta  = opengl->pickmode ? 200 : 2;
 252
 253         if (opengl->pickmode) {
 254                 gtk_gl_begin(GTK_WIDGET(opengl));
 255                 glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 256         }
 257
 258         /* Save matricies */
 259         gdouble projection[16];
 260         gint    viewport[4]; // x=0,y=0,w,h
 261         glGetDoublev(GL_PROJECTION_MATRIX, projection);
 262         glGetIntegerv(GL_VIEWPORT, viewport);
 263         glMatrixMode(GL_MODELVIEW);  glPushMatrix();
 264         glMatrixMode(GL_PROJECTION); glPushMatrix();
 265
 266         g_mutex_lock(opengl->objects_lock);
 267
 268         GritsObject *top = NULL;
 269         GPtrArray *ortho = _objects_to_array(opengl, TRUE);
 270         GPtrArray *world = _objects_to_array(opengl, FALSE);
 271
 272         /* Run perspective picking */
 273         glMatrixMode(GL_PROJECTION); glLoadIdentity();
 274         gluPickMatrix(gl_x, gl_y, delta, delta, viewport);
 275         glMultMatrixd(projection);
 276         gint world_hits = run_picking(opengl, (GdkEvent*)event, world, &top);
 277
 278         /* Run ortho picking */
 279         glMatrixMode(GL_PROJECTION); glLoadIdentity();
 280         gluPickMatrix(gl_x, gl_y, delta, delta, viewport);
 281         glMatrixMode(GL_MODELVIEW);  glLoadIdentity();
 282         glOrtho(0, viewport[2], viewport[3], 0, 1000, -1000);
 283         gint ortho_hits = run_picking(opengl, (GdkEvent*)event, ortho, &top);
 284
 285         /* Update cursor */
 286         static GdkCursor *cursor = NULL;
 287         static GdkWindow *window = NULL;
 288         if (!window || !cursor) {
 289                 cursor = gdk_cursor_new(GDK_FLEUR);
 290                 window = gtk_widget_get_window(GTK_WIDGET(opengl));
 291         }
 292         GdkCursor *topcursor = top && top->cursor ? top->cursor : cursor;
 293         gdk_window_set_cursor(window, topcursor);
 294
 295         g_debug("GritsOpenGL: on_motion_notify - hits=%d/%d,%d/%d ev=%.0lf,%.0lf",
 296                         world_hits, world->len, ortho_hits, ortho->len, gl_x, gl_y);
 297
 298         g_ptr_array_free(world, TRUE);
 299         g_ptr_array_free(ortho, TRUE);
 300
 301         g_mutex_unlock(opengl->objects_lock);
 302
 303
 304         /* Test unproject */
 305         //gdouble lat, lon, elev;
 306         //grits_viewer_unproject(GRITS_VIEWER(opengl),
 307         //              gl_x, gl_y, -1, &lat, &lon, &elev);
 308
 309         /* Cleanup */
 310         glMatrixMode(GL_PROJECTION); glPopMatrix();
 311         glMatrixMode(GL_MODELVIEW);  glPopMatrix();
 312
 313         if (opengl->pickmode)
 314                 gtk_gl_end(GTK_WIDGET(opengl));
 315
 316         return FALSE;
 317 }
 318
 319 static gboolean _draw_level(gpointer key, gpointer value, gpointer user_data)
 320 {
 321         GritsOpenGL *opengl = user_data;
 322         glong lnum = (glong)key;
 323         struct RenderLevel *level = value;
 324
 325         g_debug("GritsOpenGL: _draw_level - level=%-4ld", lnum);
 326         int nsorted = 0, nunsorted = 0;
 327         GList *cur = NULL;
 328
 329         /* Configure individual levels */
 330         if (lnum < GRITS_LEVEL_WORLD) {
 331                 /* Disable depth for background levels */
 332                 glDepthMask(FALSE);
 333                 glDisable(GL_ALPHA_TEST);
 334         } else if (lnum < GRITS_LEVEL_OVERLAY) {
 335                 /* Enable depth and alpha for world levels */
 336                 glEnable(GL_ALPHA_TEST);
 337                 glAlphaFunc(GL_GREATER, 0.1);
 338                 glDepthMask(TRUE);
 339         } else {
 340                 /* Disable depth for Overlay/HUD levels */
 341                 // This causes rendering glitches not sure why..
 342                 //glDepthMask(FALSE);
 343         }
 344
 345         /* Start ortho */
 346         if (lnum >= GRITS_LEVEL_HUD) {
 347                 glMatrixMode(GL_PROJECTION); glPushMatrix(); glLoadIdentity();
 348                 glMatrixMode(GL_MODELVIEW);  glPushMatrix(); glLoadIdentity();
 349                 gint win_width  = GTK_WIDGET(opengl)->allocation.width;
 350                 gint win_height = GTK_WIDGET(opengl)->allocation.height;
 351                 glOrtho(0, win_width, win_height, 0, 1000, -1000);
 352         }
 353
 354         /* Draw unsorted objects without depth testing,
 355          * these are polygons, etc, rather than physical objects */
 356         glDisable(GL_DEPTH_TEST);
 357         for (cur = level->unsorted.next; cur; cur = cur->next, nunsorted++)
 358                 grits_object_draw(GRITS_OBJECT(cur->data), opengl);
 359
 360         /* Draw sorted objects using depth testing
 361          * These are things that are actually part of the world */
 362         glEnable(GL_DEPTH_TEST);
 363         for (cur = level->sorted.next; cur; cur = cur->next, nsorted++)
 364                 grits_object_draw(GRITS_OBJECT(cur->data), opengl);
 365
 366         /* End ortho */
 367         if (lnum >= GRITS_LEVEL_HUD) {
 368                 glMatrixMode(GL_PROJECTION); glPopMatrix();
 369                 glMatrixMode(GL_MODELVIEW);  glPopMatrix();
 370         }
 371
 372         /* TODO: Prune empty levels */
 373
 374         g_debug("GritsOpenGL: _draw_level - drew %d,%d objects",
 375                         nunsorted, nsorted);
 376         return FALSE;
 377 }
 378
 379 static gboolean on_expose(GritsOpenGL *opengl, GdkEventExpose *event, gpointer _)
 380 {
 381         g_debug("GritsOpenGL: on_expose - begin");
 382
 383         if (opengl->pickmode)
 384                 return on_motion_notify(opengl, (GdkEventMotion*)event, NULL);
 385
 386         gtk_gl_begin(GTK_WIDGET(opengl));
 387
 388         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 389
 390         _set_visuals(opengl);
 391 #ifdef ROAM_DEBUG
 392         glColor4f(1.0, 1.0, 1.0, 1.0);
 393         glLineWidth(2);
 394         glDisable(GL_TEXTURE_2D);
 395         glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
 396         roam_sphere_draw(opengl->sphere);
 397         (void)_draw_level;
 398         //roam_sphere_draw_normals(opengl->sphere);
 399 #else
 400         g_mutex_lock(opengl->objects_lock);
 401         if (opengl->wireframe)
 402                 glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
 403         g_tree_foreach(opengl->objects, _draw_level, opengl);
 404         g_mutex_unlock(opengl->objects_lock);
 405 #endif
 406
 407         gtk_gl_end(GTK_WIDGET(opengl));
 408
 409         g_debug("GritsOpenGL: on_expose - end\n");
 410         return FALSE;
 411 }
 412
 413 static gboolean on_key_press(GritsOpenGL *opengl, GdkEventKey *event, gpointer _)
 414 {
 415         g_debug("GritsOpenGL: on_key_press - key=%x, state=%x, plus=%x",
 416                         event->keyval, event->state, GDK_plus);
 417
 418         guint kv = event->keyval;
 419         /* Testing */
 420         if (kv == GDK_w) {
 421                 opengl->wireframe = !opengl->wireframe;
 422                 gtk_widget_queue_draw(GTK_WIDGET(opengl));
 423         }
 424         if (kv == GDK_p) {
 425                 opengl->pickmode = !opengl->pickmode;
 426                 gtk_widget_queue_draw(GTK_WIDGET(opengl));
 427         }
 428 #ifdef ROAM_DEBUG
 429         else if (kv == GDK_n) roam_sphere_split_one(opengl->sphere);
 430         else if (kv == GDK_p) roam_sphere_merge_one(opengl->sphere);
 431         else if (kv == GDK_r) roam_sphere_split_merge(opengl->sphere);
 432         else if (kv == GDK_u) roam_sphere_update_errors(opengl->sphere);
 433         gtk_widget_queue_draw(GTK_WIDGET(opengl));
 434 #endif
 435         return FALSE;
 436 }
 437
 438 static gboolean on_chained_event(GritsOpenGL *opengl, GdkEvent *event, gpointer _)
 439 {
 440         _foreach_object(opengl, (GritsLevelFunc)grits_object_event, event);
 441         return FALSE;
 442 }
 443
 444 static gboolean _update_errors_cb(gpointer _opengl)
 445 {
 446         GritsOpenGL *opengl = _opengl;
 447         g_mutex_lock(opengl->sphere_lock);
 448         roam_sphere_update_errors(opengl->sphere);
 449         g_mutex_unlock(opengl->sphere_lock);
 450         opengl->ue_source = 0;
 451         return FALSE;
 452 }
 453 static void on_view_changed(GritsOpenGL *opengl,
 454                 gdouble _1, gdouble _2, gdouble _3)
 455 {
 456         g_debug("GritsOpenGL: on_view_changed");
 457         _set_visuals(opengl);
 458 #ifndef ROAM_DEBUG
 459         if (!opengl->ue_source)
 460                 opengl->ue_source = g_idle_add_full(G_PRIORITY_HIGH_IDLE+30,
 461                                 _update_errors_cb, opengl, NULL);
 462         //roam_sphere_update_errors(opengl->sphere);
 463 #else
 464         (void)_update_errors_cb;
 465 #endif
 466 }
 467
 468 static gboolean on_idle(GritsOpenGL *opengl)
 469 {
 470         //g_debug("GritsOpenGL: on_idle");
 471         g_mutex_lock(opengl->sphere_lock);
 472         if (roam_sphere_split_merge(opengl->sphere))
 473                 gtk_widget_queue_draw(GTK_WIDGET(opengl));
 474         g_mutex_unlock(opengl->sphere_lock);
 475         return TRUE;
 476 }
 477
 478 static void on_realize(GritsOpenGL *opengl, gpointer _)
 479 {
 480         g_debug("GritsOpenGL: on_realize");
 481         gtk_gl_begin(GTK_WIDGET(opengl));
 482
 483         /* Connect signals and idle functions now that opengl is fully initialized */
 484         gtk_widget_add_events(GTK_WIDGET(opengl), GDK_KEY_PRESS_MASK);
 485         g_signal_connect(opengl, "configure-event",  G_CALLBACK(on_configure),    NULL);
 486         g_signal_connect(opengl, "expose-event",     G_CALLBACK(on_expose),       NULL);
 487
 488         g_signal_connect(opengl, "key-press-event",  G_CALLBACK(on_key_press),    NULL);
 489
 490         g_signal_connect(opengl, "location-changed", G_CALLBACK(on_view_changed), NULL);
 491         g_signal_connect(opengl, "rotation-changed", G_CALLBACK(on_view_changed), NULL);
 492
 493         g_signal_connect(opengl, "motion-notify-event", G_CALLBACK(on_motion_notify), NULL);
 494         g_signal_connect_after(opengl, "key-press-event",      G_CALLBACK(on_chained_event), NULL);
 495         g_signal_connect_after(opengl, "key-release-event",    G_CALLBACK(on_chained_event), NULL);
 496         g_signal_connect_after(opengl, "button-press-event",   G_CALLBACK(on_chained_event), NULL);
 497         g_signal_connect_after(opengl, "button-release-event", G_CALLBACK(on_chained_event), NULL);
 498         g_signal_connect_after(opengl, "motion-notify-event",  G_CALLBACK(on_chained_event), NULL);
 499
 500 #ifndef ROAM_DEBUG
 501         opengl->sm_source[0] = g_timeout_add_full(G_PRIORITY_HIGH_IDLE+30, 33,  (GSourceFunc)on_idle, opengl, NULL);
 502         opengl->sm_source[1] = g_timeout_add_full(G_PRIORITY_HIGH_IDLE+10, 500, (GSourceFunc)on_idle, opengl, NULL);
 503 #else
 504         (void)on_idle;
 505         (void)_update_errors_cb;
 506 #endif
 507
 508         /* Re-queue resize incase configure was triggered before realize */
 509         gtk_widget_queue_resize(GTK_WIDGET(opengl));
 510 }
 511
 512 /*********************
 513  * GritsViewer methods *
 514  *********************/
 515 /**
 516  * grits_opengl_new:
 517  * @plugins: the plugins store to use
 518  * @prefs:   the preferences object to use
 519  *
 520  * Create a new OpenGL renderer.
 521  *
 522  * Returns: the new #GritsOpenGL
 523  */
 524 GritsViewer *grits_opengl_new(GritsPlugins *plugins, GritsPrefs *prefs)
 525 {
 526         g_debug("GritsOpenGL: new");
 527         GritsViewer *opengl = g_object_new(GRITS_TYPE_OPENGL, NULL);
 528         grits_viewer_setup(opengl, plugins, prefs);
 529         return opengl;
 530 }
 531
 532 static void grits_opengl_center_position(GritsViewer *_opengl, gdouble lat, gdouble lon, gdouble elev)
 533 {
 534         glRotatef(lon, 0, 1, 0);
 535         glRotatef(-lat, 1, 0, 0);
 536         glTranslatef(0, 0, elev2rad(elev));
 537 }
 538
 539 static void grits_opengl_project(GritsViewer *_opengl,
 540                 gdouble lat, gdouble lon, gdouble elev,
 541                 gdouble *px, gdouble *py, gdouble *pz)
 542 {
 543         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 544         gdouble x, y, z;
 545         lle2xyz(lat, lon, elev, &x, &y, &z);
 546         gluProject(x, y, z,
 547                 opengl->sphere->view->model,
 548                 opengl->sphere->view->proj,
 549                 opengl->sphere->view->view,
 550                 px, py, pz);
 551 }
 552
 553 static void grits_opengl_unproject(GritsViewer *_opengl,
 554                 gdouble px, gdouble py, gdouble pz,
 555                 gdouble *lat, gdouble *lon, gdouble *elev)
 556 {
 557         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 558         if (!opengl->sphere->view)
 559                 return;
 560         gdouble x, y, z;
 561         if (pz < 0) {
 562                 gfloat tmp = 0;
 563                 glReadPixels(px, py, 1, 1, GL_DEPTH_COMPONENT, GL_FLOAT, &tmp);
 564                 pz = tmp;
 565         }
 566         gluUnProject(px, py, pz,
 567                 opengl->sphere->view->model,
 568                 opengl->sphere->view->proj,
 569                 opengl->sphere->view->view,
 570                 &x, &y, &z);
 571         xyz2lle(x, y, z, lat, lon, elev);
 572         //g_message("GritsOpenGL: unproject - "
 573         //              "%4.0lf,%4.0lf,(%5.3lf) -> "
 574         //              "%8.0lf,%8.0lf,%8.0lf -> "
 575         //              "%6.2lf,%7.2lf,%4.0lf",
 576         //      px, py, pz, x, y, z, *lat, *lon, *elev);
 577 }
 578
 579 static void grits_opengl_set_height_func(GritsViewer *_opengl, GritsBounds *bounds,
 580                 RoamHeightFunc height_func, gpointer user_data, gboolean update)
 581 {
 582         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 583         /* TODO: get points? */
 584         g_mutex_lock(opengl->sphere_lock);
 585         GList *triangles = roam_sphere_get_intersect(opengl->sphere, TRUE,
 586                         bounds->n, bounds->s, bounds->e, bounds->w);
 587         for (GList *cur = triangles; cur; cur = cur->next) {
 588                 RoamTriangle *tri = cur->data;
 589                 RoamPoint *points[] = {tri->p.l, tri->p.m, tri->p.r, tri->split};
 590                 for (int i = 0; i < G_N_ELEMENTS(points); i++) {
 591                         if (bounds->n >= points[i]->lat && points[i]->lat >= bounds->s &&
 592                             bounds->e >= points[i]->lon && points[i]->lon >= bounds->w) {
 593                                 points[i]->height_func = height_func;
 594                                 points[i]->height_data = user_data;
 595                                 roam_point_update_height(points[i]);
 596                         }
 597                 }
 598         }
 599         g_list_free(triangles);
 600         g_mutex_unlock(opengl->sphere_lock);
 601 }
 602
 603 static void _grits_opengl_clear_height_func_rec(RoamTriangle *root)
 604 {
 605         if (!root)
 606                 return;
 607         RoamPoint *points[] = {root->p.l, root->p.m, root->p.r, root->split};
 608         for (int i = 0; i < G_N_ELEMENTS(points); i++) {
 609                 points[i]->height_func = NULL;
 610                 points[i]->height_data = NULL;
 611                 roam_point_update_height(points[i]);
 612         }
 613         _grits_opengl_clear_height_func_rec(root->kids[0]);
 614         _grits_opengl_clear_height_func_rec(root->kids[1]);
 615 }
 616
 617 static void grits_opengl_clear_height_func(GritsViewer *_opengl)
 618 {
 619         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 620         for (int i = 0; i < G_N_ELEMENTS(opengl->sphere->roots); i++)
 621                 _grits_opengl_clear_height_func_rec(opengl->sphere->roots[i]);
 622 }
 623
 624 static gpointer grits_opengl_add(GritsViewer *_opengl, GritsObject *object,
 625                 gint key, gboolean sort)
 626 {
 627         g_assert(GRITS_IS_OPENGL(_opengl));
 628         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 629         g_mutex_lock(opengl->objects_lock);
 630         struct RenderLevel *level = g_tree_lookup(opengl->objects, (gpointer)(gintptr)key);
 631         if (!level) {
 632                 level = g_new0(struct RenderLevel, 1);
 633                 g_tree_insert(opengl->objects, (gpointer)(gintptr)key, level);
 634         }
 635         GList *list = sort ? &level->sorted : &level->unsorted;
 636         /* Put the link in the list */
 637         GList *link = g_new0(GList, 1);
 638         link->data = object;
 639         link->prev = list;
 640         link->next = list->next;
 641         if (list->next)
 642                 list->next->prev = link;
 643         list->next = link;
 644         g_mutex_unlock(opengl->objects_lock);
 645         return link;
 646 }
 647
 648 static GritsObject *grits_opengl_remove(GritsViewer *_opengl, GritsObject *object)
 649 {
 650         g_assert(GRITS_IS_OPENGL(_opengl));
 651         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 652         GList *link = object->ref;
 653         g_mutex_lock(opengl->objects_lock);
 654         /* Just unlink and free it, link->prev is assured */
 655         link->prev->next = link->next;
 656         if (link->next)
 657                 link->next->prev = link->prev;
 658         g_mutex_unlock(opengl->objects_lock);
 659         object->ref    = NULL;
 660         object->viewer = NULL;
 661         g_free(link);
 662         g_object_unref(object);
 663         return object;
 664 }
 665
 666 /****************
 667  * GObject code *
 668  ****************/
 669 static int _objects_cmp(gconstpointer _a, gconstpointer _b, gpointer _)
 670 {
 671         gintptr a = (gintptr)_a, b = (gintptr)_b;
 672         return a < b ? -1 :
 673                a > b ?  1 : 0;
 674 }
 675 static void _objects_free(gpointer value)
 676 {
 677         struct RenderLevel *level = value;
 678         if (level->sorted.next)
 679                 g_list_free(level->sorted.next);
 680         if (level->unsorted.next)
 681                 g_list_free(level->unsorted.next);
 682         g_free(level);
 683 }
 684
 685 G_DEFINE_TYPE(GritsOpenGL, grits_opengl, GRITS_TYPE_VIEWER);
 686 static void grits_opengl_init(GritsOpenGL *opengl)
 687 {
 688         g_debug("GritsOpenGL: init");
 689         opengl->objects      = g_tree_new_full(_objects_cmp, NULL, NULL, _objects_free);
 690         opengl->objects_lock = g_mutex_new();
 691         opengl->sphere       = roam_sphere_new(opengl);
 692         opengl->sphere_lock  = g_mutex_new();
 693         gtk_gl_enable(GTK_WIDGET(opengl));
 694         gtk_widget_add_events(GTK_WIDGET(opengl), GDK_KEY_PRESS_MASK);
 695         g_signal_connect(opengl, "map", G_CALLBACK(on_realize), NULL);
 696 }
 697 static void grits_opengl_dispose(GObject *_opengl)
 698 {
 699         g_debug("GritsOpenGL: dispose");
 700         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 701         if (opengl->sm_source[0]) {
 702                 g_source_remove(opengl->sm_source[0]);
 703                 opengl->sm_source[0] = 0;
 704         }
 705         if (opengl->sm_source[1]) {
 706                 g_source_remove(opengl->sm_source[1]);
 707                 opengl->sm_source[1] = 0;
 708         }
 709         if (opengl->ue_source) {
 710                 g_source_remove(opengl->ue_source);
 711                 opengl->ue_source = 0;
 712         }
 713         G_OBJECT_CLASS(grits_opengl_parent_class)->dispose(_opengl);
 714 }
 715 static void grits_opengl_finalize(GObject *_opengl)
 716 {
 717         g_debug("GritsOpenGL: finalize");
 718         GritsOpenGL *opengl = GRITS_OPENGL(_opengl);
 719         roam_sphere_free(opengl->sphere);
 720         g_tree_destroy(opengl->objects);
 721         g_mutex_free(opengl->objects_lock);
 722         g_mutex_free(opengl->sphere_lock);
 723         G_OBJECT_CLASS(grits_opengl_parent_class)->finalize(_opengl);
 724 }
 725 static void grits_opengl_class_init(GritsOpenGLClass *klass)
 726 {
 727         g_debug("GritsOpenGL: class_init");
 728         GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
 729         gobject_class->finalize = grits_opengl_finalize;
 730         gobject_class->dispose = grits_opengl_dispose;
 731
 732         GritsViewerClass *viewer_class = GRITS_VIEWER_CLASS(klass);
 733         viewer_class->center_position   = grits_opengl_center_position;
 734         viewer_class->project           = grits_opengl_project;
 735         viewer_class->unproject         = grits_opengl_unproject;
 736         viewer_class->clear_height_func = grits_opengl_clear_height_func;
 737         viewer_class->set_height_func   = grits_opengl_set_height_func;
 738         viewer_class->add               = grits_opengl_add;
 739         viewer_class->remove            = grits_opengl_remove;
 740 }