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

   1 /*
   2  * Copyright (C) 2009 Andy Spencer <spenceal@rose-hulman.edu>
   3  *
   4  * This program is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 3 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 /* Tessellation, "finding intersecting triangles" */
  19 /* http://research.microsoft.com/pubs/70307/tr-2006-81.pdf */
  20 /* http://www.opengl.org/wiki/Alpha_Blending */
  21
  22 #include <config.h>
  23 #include <math.h>
  24 #include <gdk/gdkkeysyms.h>
  25 #include <gtk/gtk.h>
  26 #include <gtk/gtkgl.h>
  27 #include <GL/gl.h>
  28 #include <GL/glu.h>
  29
  30 #include "gis-opengl.h"
  31 #include "gis-util.h"
  32 #include "roam.h"
  33
  34 #define FOV_DIST   2000.0
  35 #define MPPX(dist) (4*dist/FOV_DIST)
  36
  37 // #define ROAM_DEBUG
  38
  39 /***********
  40  * Helpers *
  41  ***********/
  42 static void _gis_opengl_begin(GisOpenGL *self)
  43 {
  44         g_assert(GIS_IS_OPENGL(self));
  45
  46         GdkGLContext   *glcontext  = gtk_widget_get_gl_context(GTK_WIDGET(self));
  47         GdkGLDrawable  *gldrawable = gtk_widget_get_gl_drawable(GTK_WIDGET(self));
  48
  49         if (!gdk_gl_drawable_gl_begin(gldrawable, glcontext))
  50                 g_assert_not_reached();
  51 }
  52
  53 static void _gis_opengl_end(GisOpenGL *self)
  54 {
  55         g_assert(GIS_IS_OPENGL(self));
  56         GdkGLDrawable *gldrawable = gtk_widget_get_gl_drawable(GTK_WIDGET(self));
  57         gdk_gl_drawable_gl_end(gldrawable);
  58 }
  59
  60 /*************
  61  * ROAM Code *
  62  *************/
  63 static void _set_visuals(GisOpenGL *self)
  64 {
  65         glMatrixMode(GL_MODELVIEW);
  66         glLoadIdentity();
  67
  68         /* Camera 1 */
  69         double lat, lon, elev, rx, ry, rz;
  70         gis_viewer_get_location(GIS_VIEWER(self), &lat, &lon, &elev);
  71         gis_viewer_get_rotation(GIS_VIEWER(self), &rx, &ry, &rz);
  72         glRotatef(rx, 1, 0, 0);
  73         glRotatef(rz, 0, 0, 1);
  74
  75         /* Lighting */
  76 #ifdef ROAM_DEBUG
  77         float light_ambient[]  = {0.7f, 0.7f, 0.7f, 1.0f};
  78         float light_diffuse[]  = {2.0f, 2.0f, 2.0f, 1.0f};
  79 #else
  80         float light_ambient[]  = {0.2f, 0.2f, 0.2f, 1.0f};
  81         float light_diffuse[]  = {5.0f, 5.0f, 5.0f, 1.0f};
  82 #endif
  83         float light_position[] = {-13*EARTH_R, 1*EARTH_R, 3*EARTH_R, 1.0f};
  84         glLightfv(GL_LIGHT0, GL_AMBIENT,  light_ambient);
  85         glLightfv(GL_LIGHT0, GL_DIFFUSE,  light_diffuse);
  86         glLightfv(GL_LIGHT0, GL_POSITION, light_position);
  87         glEnable(GL_LIGHT0);
  88         glEnable(GL_LIGHTING);
  89
  90         float material_ambient[]  = {0.2, 0.2, 0.2, 1.0};
  91         float material_diffuse[]  = {0.8, 0.8, 0.8, 1.0};
  92         float material_specular[] = {0.0, 0.0, 0.0, 1.0};
  93         float material_emission[] = {0.0, 0.0, 0.0, 1.0};
  94         glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT,  material_ambient);
  95         glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE,  material_diffuse);
  96         glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, material_specular);
  97         glMaterialfv(GL_FRONT_AND_BACK, GL_EMISSION, material_emission);
  98         glDisable(GL_TEXTURE_2D);
  99         glDisable(GL_COLOR_MATERIAL);
 100
 101         /* Camera 2 */
 102         glTranslatef(0, 0, -elev2rad(elev));
 103         glRotatef(lat, 1, 0, 0);
 104         glRotatef(-lon, 0, 1, 0);
 105
 106         /* Misc */
 107         gdouble rg   = MAX(0, 1-(elev/20000));
 108         gdouble blue = MAX(0, 1-(elev/50000));
 109         glClearColor(MIN(0.65,rg), MIN(0.65,rg), MIN(1,blue), 1.0f);
 110         glColor4f(1, 1, 1, 1);
 111
 112         glDisable(GL_ALPHA_TEST);
 113
 114         glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 115         glEnable(GL_BLEND);
 116
 117 #ifndef ROAM_DEBUG
 118         glCullFace(GL_BACK);
 119         glEnable(GL_CULL_FACE);
 120 #endif
 121
 122         glClearDepth(1.0);
 123         glDepthFunc(GL_LEQUAL);
 124         glEnable(GL_DEPTH_TEST);
 125
 126         glEnable(GL_LINE_SMOOTH);
 127
 128         glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
 129         //glShadeModel(GL_FLAT);
 130
 131         roam_sphere_update_view(self->sphere);
 132 }
 133
 134
 135 /*************
 136  * Callbacks *
 137  *************/
 138 static void on_realize(GisOpenGL *self, gpointer _)
 139 {
 140         g_debug("GisOpenGL: on_realize");
 141         _set_visuals(self);
 142         roam_sphere_update_errors(self->sphere);
 143 }
 144 static gboolean on_configure(GisOpenGL *self, GdkEventConfigure *event, gpointer _)
 145 {
 146         g_debug("GisOpenGL: on_configure");
 147         _gis_opengl_begin(self);
 148
 149         double width  = GTK_WIDGET(self)->allocation.width;
 150         double height = GTK_WIDGET(self)->allocation.height;
 151         glViewport(0, 0, width, height);
 152
 153         glMatrixMode(GL_PROJECTION);
 154         glLoadIdentity();
 155         double ang = atan(height/FOV_DIST);
 156         gluPerspective(rad2deg(ang)*2, width/height, 1, 20*EARTH_R);
 157
 158 #ifndef ROAM_DEBUG
 159         roam_sphere_update_errors(self->sphere);
 160 #endif
 161
 162         _gis_opengl_end(self);
 163         return FALSE;
 164 }
 165
 166 static void on_expose_plugin(GisPlugin *plugin, gchar *name, GisOpenGL *self)
 167 {
 168         _set_visuals(self);
 169         glMatrixMode(GL_PROJECTION); glPushMatrix();
 170         glMatrixMode(GL_MODELVIEW);  glPushMatrix();
 171         gis_plugin_expose(plugin);
 172         glMatrixMode(GL_PROJECTION); glPopMatrix();
 173         glMatrixMode(GL_MODELVIEW);  glPopMatrix();
 174 }
 175 static gboolean on_expose(GisOpenGL *self, GdkEventExpose *event, gpointer _)
 176 {
 177         g_debug("GisOpenGL: on_expose - begin");
 178         _gis_opengl_begin(self);
 179
 180         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 181
 182 #ifndef ROAM_DEBUG
 183         gis_plugins_foreach(GIS_VIEWER(self)->plugins, G_CALLBACK(on_expose_plugin), self);
 184
 185         if (self->wireframe) {
 186                 _set_visuals(self);
 187                 glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
 188                 roam_sphere_draw(self->sphere);
 189         }
 190 #else
 191         _set_visuals(self);
 192         glColor4f(0.0, 0.0, 9.0, 0.6);
 193         glDisable(GL_TEXTURE_2D);
 194         glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
 195         roam_sphere_draw(self->sphere);
 196
 197         //roam_sphere_draw_normals(self->sphere);
 198 #endif
 199
 200         GdkGLDrawable *gldrawable = gtk_widget_get_gl_drawable(GTK_WIDGET(self));
 201         gdk_gl_drawable_swap_buffers(gldrawable);
 202
 203         _gis_opengl_end(self);
 204         g_debug("GisOpenGL: on_expose - end\n");
 205         return FALSE;
 206 }
 207
 208 static gboolean on_key_press(GisOpenGL *self, GdkEventKey *event, gpointer _)
 209 {
 210         g_debug("GisOpenGL: on_key_press - key=%x, state=%x, plus=%x",
 211                         event->keyval, event->state, GDK_plus);
 212
 213         guint kv = event->keyval;
 214         gdk_threads_leave();
 215         /* Testing */
 216         if (kv == GDK_w) {
 217                 self->wireframe = !self->wireframe;
 218                 gtk_widget_queue_draw(GTK_WIDGET(self));
 219         }
 220 #ifdef ROAM_DEBUG
 221         else if (kv == GDK_n) roam_sphere_split_one(self->sphere);
 222         else if (kv == GDK_p) roam_sphere_merge_one(self->sphere);
 223         else if (kv == GDK_r) roam_sphere_split_merge(self->sphere);
 224         else if (kv == GDK_u) roam_sphere_update_errors(self->sphere);
 225         gdk_threads_enter();
 226         gtk_widget_queue_draw(GTK_WIDGET(self));
 227 #else
 228         gdk_threads_enter();
 229 #endif
 230
 231         return TRUE;
 232 }
 233
 234 static gboolean _update_errors_cb(gpointer sphere)
 235 {
 236         roam_sphere_update_errors(sphere);
 237         return FALSE;
 238 }
 239 static void on_view_changed(GisOpenGL *self,
 240                 gdouble _1, gdouble _2, gdouble _3)
 241 {
 242         g_debug("GisOpenGL: on_view_changed");
 243         gdk_threads_enter();
 244         _gis_opengl_begin(self);
 245         _set_visuals(self);
 246 #ifndef ROAM_DEBUG
 247         g_idle_add_full(G_PRIORITY_HIGH_IDLE+30, _update_errors_cb, self->sphere, NULL);
 248         //roam_sphere_update_errors(self->sphere);
 249 #endif
 250         _gis_opengl_end(self);
 251         gdk_threads_leave();
 252 }
 253
 254 static gboolean on_idle(GisOpenGL *self)
 255 {
 256         //g_debug("GisOpenGL: on_idle");
 257         gdk_threads_enter();
 258         _gis_opengl_begin(self);
 259         if (roam_sphere_split_merge(self->sphere))
 260                 gtk_widget_queue_draw(GTK_WIDGET(self));
 261         _gis_opengl_end(self);
 262         gdk_threads_leave();
 263         return TRUE;
 264 }
 265
 266
 267 /*********************
 268  * GisViewer methods *
 269  *********************/
 270 GisViewer *gis_opengl_new(GisPlugins *plugins)
 271 {
 272         g_debug("GisOpenGL: new");
 273         GisViewer *self = g_object_new(GIS_TYPE_OPENGL, NULL);
 274         self->plugins = plugins;
 275         return self;
 276 }
 277
 278 static void gis_opengl_center_position(GisViewer *_self, gdouble lat, gdouble lon, gdouble elev)
 279 {
 280         GisOpenGL *self = GIS_OPENGL(_self);
 281         glRotatef(lon, 0, 1, 0);
 282         glRotatef(-lat, 1, 0, 0);
 283         glTranslatef(0, 0, elev2rad(elev));
 284 }
 285
 286 static void gis_opengl_project(GisViewer *_self,
 287                 gdouble lat, gdouble lon, gdouble elev,
 288                 gdouble *px, gdouble *py, gdouble *pz)
 289 {
 290         GisOpenGL *self = GIS_OPENGL(_self);
 291         gdouble x, y, z;
 292         lle2xyz(lat, lon, elev, &x, &y, &z);
 293         gluProject(x, y, z,
 294                 self->sphere->view->model,
 295                 self->sphere->view->proj,
 296                 self->sphere->view->view,
 297                 px, py, pz);
 298 }
 299
 300 static void gis_opengl_render_tile(GisViewer *_self, GisTile *tile)
 301 {
 302         GisOpenGL *self = GIS_OPENGL(_self);
 303         if (!tile || !tile->data)
 304                 return;
 305         GList *triangles = roam_sphere_get_intersect(self->sphere,
 306                         tile->edge.n, tile->edge.s, tile->edge.e, tile->edge.w);
 307         if (!triangles)
 308                 g_warning("GisOpenGL: render_tiles - No triangles to draw: edges=%f,%f,%f,%f",
 309                         tile->edge.n, tile->edge.s, tile->edge.e, tile->edge.w);
 310         //g_message("rendering %4d triangles for tile edges=%7.2f,%7.2f,%7.2f,%7.2f",
 311         //              g_list_length(triangles), tile->edge.n, tile->edge.s, tile->edge.e, tile->edge.w);
 312         for (GList *cur = triangles; cur; cur = cur->next) {
 313                 RoamTriangle *tri = cur->data;
 314
 315                 gdouble lat[3] = {tri->p.r->lat, tri->p.m->lat, tri->p.l->lat};
 316                 gdouble lon[3] = {tri->p.r->lon, tri->p.m->lon, tri->p.l->lon};
 317
 318                 if (lon[0] < -90 || lon[1] < -90 || lon[2] < -90) {
 319                         if (lon[0] > 90) lon[0] -= 360;
 320                         if (lon[1] > 90) lon[1] -= 360;
 321                         if (lon[2] > 90) lon[2] -= 360;
 322                 }
 323
 324                 gdouble n = tile->edge.n;
 325                 gdouble s = tile->edge.s;
 326                 gdouble e = tile->edge.e;
 327                 gdouble w = tile->edge.w;
 328
 329                 gdouble londist = e - w;
 330                 gdouble latdist = n - s;
 331
 332                 gdouble xy[][3] = {
 333                         {(lon[0]-w)/londist, 1-(lat[0]-s)/latdist},
 334                         {(lon[1]-w)/londist, 1-(lat[1]-s)/latdist},
 335                         {(lon[2]-w)/londist, 1-(lat[2]-s)/latdist},
 336                 };
 337
 338                 glEnable(GL_TEXTURE_2D);
 339                 glBindTexture(GL_TEXTURE_2D, *(guint*)tile->data);
 340                 glBegin(GL_TRIANGLES);
 341                 glNormal3dv(tri->p.r->norm); glTexCoord2dv(xy[0]); glVertex3dv((double*)tri->p.r);
 342                 glNormal3dv(tri->p.m->norm); glTexCoord2dv(xy[1]); glVertex3dv((double*)tri->p.m);
 343                 glNormal3dv(tri->p.l->norm); glTexCoord2dv(xy[2]); glVertex3dv((double*)tri->p.l);
 344                 glEnd();
 345         }
 346         g_list_free(triangles);
 347 }
 348
 349 static void gis_opengl_render_tiles(GisViewer *_self, GisTile *tile)
 350 {
 351         GisOpenGL *self = GIS_OPENGL(_self);
 352         /* Only render children if possible */
 353         gboolean has_children = TRUE;
 354         GisTile *child;
 355         gis_tile_foreach(tile, child)
 356                 if (!child || !child->data)
 357                         has_children = FALSE;
 358         if (has_children)
 359                 /* Only render children */
 360                 gis_tile_foreach(tile, child)
 361                         gis_opengl_render_tiles(_self, child);
 362         else
 363                 /* No children, render this tile */
 364                 gis_opengl_render_tile(_self, tile);
 365 }
 366
 367 static void gis_opengl_set_height_func(GisViewer *_self, GisTile *tile,
 368                 RoamHeightFunc height_func, gpointer user_data, gboolean update)
 369 {
 370         GisOpenGL *self = GIS_OPENGL(_self);
 371         if (!tile)
 372                 return;
 373         /* TODO: get points? */
 374         GList *triangles = roam_sphere_get_intersect(self->sphere,
 375                         tile->edge.n, tile->edge.s, tile->edge.e, tile->edge.w);
 376         for (GList *cur = triangles; cur; cur = cur->next) {
 377                 RoamTriangle *tri = cur->data;
 378                 RoamPoint *points[] = {tri->p.l, tri->p.m, tri->p.r, tri->split};
 379                 for (int i = 0; i < G_N_ELEMENTS(points); i++) {
 380                         points[i]->height_func = height_func;
 381                         points[i]->height_data = user_data;
 382                         roam_point_update_height(points[i]);
 383                 }
 384         }
 385         g_list_free(triangles);
 386 }
 387
 388 static void _gis_opengl_clear_height_func_rec(RoamTriangle *root)
 389 {
 390         if (!root)
 391                 return;
 392         RoamPoint *points[] = {root->p.l, root->p.m, root->p.r, root->split};
 393         for (int i = 0; i < G_N_ELEMENTS(points); i++) {
 394                 points[i]->height_func = NULL;
 395                 points[i]->height_data = NULL;
 396                 roam_point_update_height(points[i]);
 397         }
 398         _gis_opengl_clear_height_func_rec(root->kids[0]);
 399         _gis_opengl_clear_height_func_rec(root->kids[1]);
 400 }
 401
 402 static void gis_opengl_clear_height_func(GisViewer *_self)
 403 {
 404         GisOpenGL *self = GIS_OPENGL(_self);
 405         for (int i = 0; i < G_N_ELEMENTS(self->sphere->roots); i++)
 406                 _gis_opengl_clear_height_func_rec(self->sphere->roots[i]);
 407 }
 408
 409 static void gis_opengl_begin(GisViewer *_self)
 410 {
 411         g_assert(GIS_IS_OPENGL(_self));
 412         _gis_opengl_begin(GIS_OPENGL(_self));
 413 }
 414
 415 static void gis_opengl_end(GisViewer *_self)
 416 {
 417         g_assert(GIS_IS_OPENGL(_self));
 418         _gis_opengl_end(GIS_OPENGL(_self));
 419 }
 420
 421 /****************
 422  * GObject code *
 423  ****************/
 424 G_DEFINE_TYPE(GisOpenGL, gis_opengl, GIS_TYPE_VIEWER);
 425 static void gis_opengl_init(GisOpenGL *self)
 426 {
 427         g_debug("GisOpenGL: init");
 428         /* OpenGL setup */
 429         GdkGLConfig *glconfig = gdk_gl_config_new_by_mode(
 430                         GDK_GL_MODE_RGBA   | GDK_GL_MODE_DEPTH |
 431                         GDK_GL_MODE_DOUBLE | GDK_GL_MODE_ALPHA);
 432         if (!glconfig)
 433                 g_error("Failed to create glconfig");
 434         if (!gtk_widget_set_gl_capability(GTK_WIDGET(self),
 435                                 glconfig, NULL, TRUE, GDK_GL_RGBA_TYPE))
 436                 g_error("GL lacks required capabilities");
 437         g_object_unref(glconfig);
 438
 439         gtk_widget_set_size_request(GTK_WIDGET(self), 600, 550);
 440         gtk_widget_set_events(GTK_WIDGET(self),
 441                         GDK_BUTTON_PRESS_MASK |
 442                         GDK_ENTER_NOTIFY_MASK |
 443                         GDK_KEY_PRESS_MASK);
 444         g_object_set(self, "can-focus", TRUE, NULL);
 445
 446         self->sphere = roam_sphere_new(self);
 447
 448 #ifndef ROAM_DEBUG
 449         self->sm_source[0] = g_timeout_add_full(G_PRIORITY_HIGH_IDLE+30, 33,  (GSourceFunc)on_idle, self, NULL);
 450         self->sm_source[1] = g_timeout_add_full(G_PRIORITY_HIGH_IDLE+10, 500, (GSourceFunc)on_idle, self, NULL);
 451 #endif
 452
 453         g_signal_connect(self, "realize",            G_CALLBACK(on_realize),      NULL);
 454         g_signal_connect(self, "configure-event",    G_CALLBACK(on_configure),    NULL);
 455         g_signal_connect(self, "expose-event",       G_CALLBACK(on_expose),       NULL);
 456
 457         g_signal_connect(self, "key-press-event",    G_CALLBACK(on_key_press),    NULL);
 458
 459         g_signal_connect(self, "location-changed",   G_CALLBACK(on_view_changed), NULL);
 460         g_signal_connect(self, "rotation-changed",   G_CALLBACK(on_view_changed), NULL);
 461 }
 462 static void gis_opengl_dispose(GObject *_self)
 463 {
 464         g_debug("GisOpenGL: dispose");
 465         GisOpenGL *self = GIS_OPENGL(_self);
 466         if (self->sm_source[0]) {
 467                 g_source_remove(self->sm_source[0]);
 468                 self->sm_source[0] = 0;
 469         }
 470         if (self->sm_source[1]) {
 471                 g_source_remove(self->sm_source[1]);
 472                 self->sm_source[1] = 0;
 473         }
 474         if (self->sphere) {
 475                 roam_sphere_free(self->sphere);
 476                 self->sphere = NULL;
 477         }
 478         G_OBJECT_CLASS(gis_opengl_parent_class)->dispose(_self);
 479 }
 480 static void gis_opengl_class_init(GisOpenGLClass *klass)
 481 {
 482         g_debug("GisOpenGL: class_init");
 483         GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
 484         gobject_class->dispose     = gis_opengl_dispose;
 485
 486         GisViewerClass *viewer_class = GIS_VIEWER_CLASS(klass);
 487         viewer_class->center_position   = gis_opengl_center_position;
 488         viewer_class->project           = gis_opengl_project;
 489         viewer_class->clear_height_func = gis_opengl_clear_height_func;
 490         viewer_class->set_height_func   = gis_opengl_set_height_func;
 491         viewer_class->render_tile       = gis_opengl_render_tile;
 492         viewer_class->render_tiles      = gis_opengl_render_tiles;
 493         viewer_class->begin             = gis_opengl_begin;
 494         viewer_class->end               = gis_opengl_end;
 495 }