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 "roam.h"
  32
  33 #define FOV_DIST   2000.0
  34 #define MPPX(dist) (4*dist/FOV_DIST)
  35
  36 // #define ROAM_DEBUG
  37
  38 /*************
  39  * ROAM Code *
  40  *************/
  41 static void set_visuals(GisOpenGL *self)
  42 {
  43         glMatrixMode(GL_MODELVIEW);
  44         glLoadIdentity();
  45
  46         /* Camera 1 */
  47         double lat, lon, elev, rx, ry, rz;
  48         gis_view_get_location(self->view, &lat, &lon, &elev);
  49         gis_view_get_rotation(self->view, &rx, &ry, &rz);
  50         glRotatef(rx, 1, 0, 0);
  51         glRotatef(rz, 0, 0, 1);
  52
  53         /* Lighting */
  54 #ifdef ROAM_DEBUG
  55         float light_ambient[]  = {0.7f, 0.7f, 0.7f, 1.0f};
  56         float light_diffuse[]  = {2.0f, 2.0f, 2.0f, 1.0f};
  57 #else
  58         float light_ambient[]  = {0.2f, 0.2f, 0.2f, 1.0f};
  59         float light_diffuse[]  = {5.0f, 5.0f, 5.0f, 1.0f};
  60 #endif
  61         float light_position[] = {-13*EARTH_R, 1*EARTH_R, 3*EARTH_R, 1.0f};
  62         glLightfv(GL_LIGHT0, GL_AMBIENT,  light_ambient);
  63         glLightfv(GL_LIGHT0, GL_DIFFUSE,  light_diffuse);
  64         glLightfv(GL_LIGHT0, GL_POSITION, light_position);
  65         glEnable(GL_LIGHT0);
  66         glEnable(GL_LIGHTING);
  67
  68         float material_ambient[]  = {0.2, 0.2, 0.2, 1.0};
  69         float material_diffuse[]  = {0.8, 0.8, 0.8, 1.0};
  70         float material_specular[] = {0.0, 0.0, 0.0, 1.0};
  71         float material_emission[] = {0.0, 0.0, 0.0, 1.0};
  72         glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT,  material_ambient);
  73         glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE,  material_diffuse);
  74         glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, material_specular);
  75         glMaterialfv(GL_FRONT_AND_BACK, GL_EMISSION, material_emission);
  76         glDisable(GL_TEXTURE_2D);
  77         glDisable(GL_COLOR_MATERIAL);
  78
  79         /* Camera 2 */
  80         glTranslatef(0, 0, -elev2rad(elev));
  81         glRotatef(lat, 1, 0, 0);
  82         glRotatef(-lon, 0, 1, 0);
  83
  84         /* Misc */
  85         gdouble rg   = MAX(0, 1-(elev/20000));
  86         gdouble blue = MAX(0, 1-(elev/50000));
  87         glClearColor(MIN(0.65,rg), MIN(0.65,rg), MIN(1,blue), 1.0f);
  88
  89         glDisable(GL_ALPHA_TEST);
  90
  91         glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
  92         glEnable(GL_BLEND);
  93
  94 #ifndef ROAM_DEBUG
  95         glCullFace(GL_BACK);
  96         glEnable(GL_CULL_FACE);
  97 #endif
  98
  99         glClearDepth(1.0);
 100         glDepthFunc(GL_LEQUAL);
 101         glEnable(GL_DEPTH_TEST);
 102
 103         glEnable(GL_LINE_SMOOTH);
 104
 105         glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
 106         //glShadeModel(GL_FLAT);
 107 }
 108
 109
 110 /*************
 111  * Callbacks *
 112  *************/
 113 static void on_realize(GisOpenGL *self, gpointer _)
 114 {
 115         g_debug("GisOpenGL: on_realize");
 116         set_visuals(self);
 117         roam_sphere_update_errors(self->sphere);
 118 }
 119 static gboolean on_configure(GisOpenGL *self, GdkEventConfigure *event, gpointer _)
 120 {
 121         g_debug("GisOpenGL: on_configure");
 122         gis_opengl_begin(self);
 123
 124         double width  = GTK_WIDGET(self)->allocation.width;
 125         double height = GTK_WIDGET(self)->allocation.height;
 126         glViewport(0, 0, width, height);
 127
 128         glMatrixMode(GL_PROJECTION);
 129         glLoadIdentity();
 130         double ang = atan(height/FOV_DIST);
 131         gluPerspective(rad2deg(ang)*2, width/height, 1, 20*EARTH_R);
 132
 133 #ifndef ROAM_DEBUG
 134         roam_sphere_update_errors(self->sphere);
 135 #endif
 136
 137         gis_opengl_end(self);
 138         return FALSE;
 139 }
 140
 141 static void on_expose_plugin(GisPlugin *plugin, gchar *name, GisOpenGL *self)
 142 {
 143         set_visuals(self);
 144         glMatrixMode(GL_PROJECTION); glPushMatrix();
 145         glMatrixMode(GL_MODELVIEW);  glPushMatrix();
 146         gis_plugin_expose(plugin);
 147         glMatrixMode(GL_PROJECTION); glPopMatrix();
 148         glMatrixMode(GL_MODELVIEW);  glPopMatrix();
 149 }
 150 static gboolean on_expose(GisOpenGL *self, GdkEventExpose *event, gpointer _)
 151 {
 152         g_debug("GisOpenGL: on_expose - begin");
 153         gis_opengl_begin(self);
 154
 155         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 156
 157 #ifndef ROAM_DEBUG
 158         gis_plugins_foreach(self->plugins, G_CALLBACK(on_expose_plugin), self);
 159
 160         if (self->wireframe) {
 161                 set_visuals(self);
 162                 glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
 163                 roam_sphere_draw(self->sphere);
 164         }
 165 #else
 166         set_visuals(self);
 167         glColor4f(0.0, 0.0, 9.0, 0.6);
 168         glDisable(GL_TEXTURE_2D);
 169         glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
 170         roam_sphere_draw(self->sphere);
 171
 172         //roam_sphere_draw_normals(self->sphere);
 173 #endif
 174
 175         set_visuals(self);
 176         gis_opengl_end(self);
 177         gis_opengl_flush(self);
 178         g_debug("GisOpenGL: on_expose - end\n");
 179         return FALSE;
 180 }
 181
 182 static gboolean on_button_press(GisOpenGL *self, GdkEventButton *event, gpointer _)
 183 {
 184         g_debug("GisOpenGL: on_button_press - Grabbing focus");
 185         gtk_widget_grab_focus(GTK_WIDGET(self));
 186         return TRUE;
 187 }
 188
 189 static gboolean on_key_press(GisOpenGL *self, GdkEventKey *event, gpointer _)
 190 {
 191         g_debug("GisOpenGL: on_key_press - key=%x, state=%x, plus=%x",
 192                         event->keyval, event->state, GDK_plus);
 193
 194         double lat, lon, elev, pan;
 195         gis_view_get_location(self->view, &lat, &lon, &elev);
 196         pan = MIN(elev/(EARTH_R/2), 30);
 197         guint kv = event->keyval;
 198         if      (kv == GDK_Left  || kv == GDK_h) gis_view_pan(self->view,  0,  -pan, 0);
 199         else if (kv == GDK_Down  || kv == GDK_j) gis_view_pan(self->view, -pan, 0,   0);
 200         else if (kv == GDK_Up    || kv == GDK_k) gis_view_pan(self->view,  pan, 0,   0);
 201         else if (kv == GDK_Right || kv == GDK_l) gis_view_pan(self->view,  0,   pan, 0);
 202         else if (kv == GDK_minus || kv == GDK_o) gis_view_zoom(self->view, 10./9);
 203         else if (kv == GDK_plus  || kv == GDK_i) gis_view_zoom(self->view, 9./10);
 204         else if (kv == GDK_H) gis_view_rotate(self->view,  0, 0, -2);
 205         else if (kv == GDK_J) gis_view_rotate(self->view,  2, 0,  0);
 206         else if (kv == GDK_K) gis_view_rotate(self->view, -2, 0,  0);
 207         else if (kv == GDK_L) gis_view_rotate(self->view,  0, 0,  2);
 208
 209         /* Testing */
 210         else if (kv == GDK_w) {self->wireframe = !self->wireframe; gtk_widget_queue_draw(GTK_WIDGET(self));}
 211 #ifdef ROAM_DEBUG
 212         else if (kv == GDK_n) roam_sphere_split_one(self->sphere);
 213         else if (kv == GDK_p) roam_sphere_merge_one(self->sphere);
 214         else if (kv == GDK_r) roam_sphere_split_merge(self->sphere);
 215         else if (kv == GDK_u) roam_sphere_update_errors(self->sphere);
 216         gtk_widget_queue_draw(GTK_WIDGET(self));
 217 #endif
 218
 219         return TRUE;
 220 }
 221
 222 static void on_view_changed(GisView *view,
 223                 gdouble _1, gdouble _2, gdouble _3, GisOpenGL *self)
 224 {
 225         g_debug("GisOpenGL: on_view_changed");
 226         gis_opengl_begin(self);
 227         set_visuals(self);
 228 #ifndef ROAM_DEBUG
 229         roam_sphere_update_errors(self->sphere);
 230 #endif
 231         gis_opengl_redraw(self);
 232         gis_opengl_end(self);
 233 }
 234
 235 static gboolean on_idle(GisOpenGL *self)
 236 {
 237         //g_debug("GisOpenGL: on_idle");
 238         gis_opengl_begin(self);
 239         if (roam_sphere_split_merge(self->sphere))
 240                 gis_opengl_redraw(self);
 241         gis_opengl_end(self);
 242         return TRUE;
 243 }
 244
 245
 246 /***********
 247  * Methods *
 248  ***********/
 249 GisOpenGL *gis_opengl_new(GisWorld *world, GisView *view, GisPlugins *plugins)
 250 {
 251         g_debug("GisOpenGL: new");
 252         GisOpenGL *self = g_object_new(GIS_TYPE_OPENGL, NULL);
 253         self->world   = world;
 254         self->view    = view;
 255         self->plugins = plugins;
 256         g_object_ref(world);
 257         g_object_ref(view);
 258
 259         g_signal_connect(self->view, "location-changed", G_CALLBACK(on_view_changed), self);
 260         g_signal_connect(self->view, "rotation-changed", G_CALLBACK(on_view_changed), self);
 261
 262         self->sphere = roam_sphere_new(self);
 263
 264         return g_object_ref(self);
 265 }
 266
 267 void gis_opengl_center_position(GisOpenGL *self, gdouble lat, gdouble lon, gdouble elev)
 268 {
 269         glRotatef(lon, 0, 1, 0);
 270         glRotatef(-lat, 1, 0, 0);
 271         glTranslatef(0, 0, elev2rad(elev));
 272 }
 273
 274 void gis_opengl_redraw(GisOpenGL *self)
 275 {
 276         g_debug("GisOpenGL: redraw");
 277         gtk_widget_queue_draw(GTK_WIDGET(self));
 278 }
 279 void gis_opengl_begin(GisOpenGL *self)
 280 {
 281         g_assert(GIS_IS_OPENGL(self));
 282
 283         GdkGLContext   *glcontext  = gtk_widget_get_gl_context(GTK_WIDGET(self));
 284         GdkGLDrawable  *gldrawable = gtk_widget_get_gl_drawable(GTK_WIDGET(self));
 285
 286         if (!gdk_gl_drawable_gl_begin(gldrawable, glcontext))
 287                 g_assert_not_reached();
 288 }
 289 void gis_opengl_end(GisOpenGL *self)
 290 {
 291         g_assert(GIS_IS_OPENGL(self));
 292         GdkGLDrawable *gldrawable = gtk_widget_get_gl_drawable(GTK_WIDGET(self));
 293         gdk_gl_drawable_gl_end(gldrawable);
 294 }
 295 void gis_opengl_flush(GisOpenGL *self)
 296 {
 297         g_assert(GIS_IS_OPENGL(self));
 298         GdkGLDrawable *gldrawable = gtk_widget_get_gl_drawable(GTK_WIDGET(self));
 299         if (gdk_gl_drawable_is_double_buffered(gldrawable))
 300                 gdk_gl_drawable_swap_buffers(gldrawable);
 301         else
 302                 glFlush();
 303         gdk_gl_drawable_gl_end(gldrawable);
 304 }
 305
 306
 307 /****************
 308  * GObject code *
 309  ****************/
 310 G_DEFINE_TYPE(GisOpenGL, gis_opengl, GTK_TYPE_DRAWING_AREA);
 311 static void gis_opengl_init(GisOpenGL *self)
 312 {
 313         g_debug("GisOpenGL: init");
 314         /* OpenGL setup */
 315         GdkGLConfig *glconfig = gdk_gl_config_new_by_mode(
 316                         GDK_GL_MODE_RGBA   | GDK_GL_MODE_DEPTH |
 317                         GDK_GL_MODE_DOUBLE | GDK_GL_MODE_ALPHA);
 318         if (!glconfig)
 319                 g_error("Failed to create glconfig");
 320         if (!gtk_widget_set_gl_capability(GTK_WIDGET(self),
 321                                 glconfig, NULL, TRUE, GDK_GL_RGBA_TYPE))
 322                 g_error("GL lacks required capabilities");
 323         g_object_unref(glconfig);
 324
 325         gtk_widget_set_size_request(GTK_WIDGET(self), 600, 550);
 326         gtk_widget_set_events(GTK_WIDGET(self),
 327                         GDK_BUTTON_PRESS_MASK |
 328                         GDK_ENTER_NOTIFY_MASK |
 329                         GDK_KEY_PRESS_MASK);
 330         g_object_set(self, "can-focus", TRUE, NULL);
 331
 332 #ifndef ROAM_DEBUG
 333         self->sm_source = g_timeout_add(10, (GSourceFunc)on_idle, self);
 334 #endif
 335
 336         g_signal_connect(self, "realize",            G_CALLBACK(on_realize),      NULL);
 337         g_signal_connect(self, "configure-event",    G_CALLBACK(on_configure),    NULL);
 338         g_signal_connect(self, "expose-event",       G_CALLBACK(on_expose),       NULL);
 339
 340         g_signal_connect(self, "button-press-event", G_CALLBACK(on_button_press), NULL);
 341         g_signal_connect(self, "enter-notify-event", G_CALLBACK(on_button_press), NULL);
 342         g_signal_connect(self, "key-press-event",    G_CALLBACK(on_key_press),    NULL);
 343 }
 344 static GObject *gis_opengl_constructor(GType gtype, guint n_properties,
 345                 GObjectConstructParam *properties)
 346 {
 347         g_debug("GisOpengl: constructor");
 348         GObjectClass *parent_class = G_OBJECT_CLASS(gis_opengl_parent_class);
 349         return parent_class->constructor(gtype, n_properties, properties);
 350 }
 351 static void gis_opengl_dispose(GObject *_self)
 352 {
 353         g_debug("GisOpenGL: dispose");
 354         GisOpenGL *self = GIS_OPENGL(_self);
 355         if (self->sm_source) {
 356                 g_source_remove(self->sm_source);
 357                 self->sm_source = 0;
 358         }
 359         if (self->sphere) {
 360                 roam_sphere_free(self->sphere);
 361                 self->sphere = NULL;
 362         }
 363         if (self->world) {
 364                 g_object_unref(self->world);
 365                 self->world = NULL;
 366         }
 367         if (self->view) {
 368                 g_object_unref(self->view);
 369                 self->view = NULL;
 370         }
 371         G_OBJECT_CLASS(gis_opengl_parent_class)->dispose(_self);
 372 }
 373 static void gis_opengl_finalize(GObject *_self)
 374 {
 375         g_debug("GisOpenGL: finalize");
 376         GisOpenGL *self = GIS_OPENGL(_self);
 377         G_OBJECT_CLASS(gis_opengl_parent_class)->finalize(_self);
 378 }
 379 static void gis_opengl_class_init(GisOpenGLClass *klass)
 380 {
 381         g_debug("GisOpenGL: class_init");
 382         GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
 383         gobject_class->constructor  = gis_opengl_constructor;
 384         gobject_class->dispose      = gis_opengl_dispose;
 385         gobject_class->finalize     = gis_opengl_finalize;
 386 }