Pileus Git - grits/blob - src/objects/grits-object.c

   1 /*
   2  * Copyright (C) 2009-2010 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-object
  20  * @short_description: Base class for drawing operations
  21  *
  22  * Objects in grits are things which can be added to the viewer and will be
  23  * displayed to the user. Each object has information such as it's location and
  24  * level of detail which are used by the viewer to determine which objects
  25  * should be drawn.
  26  *
  27  * Each #GritsObject is also a #GObject, but not every GObject in grits is a
  28  * GritsObject. The "Object" part of the name is just coincidence.
  29  */
  30
  31 #include <config.h>
  32 #include <math.h>
  33 #include <GL/gl.h>
  34
  35 #include "grits-object.h"
  36
  37 /* Constants */
  38 enum {
  39         SIG_ENTER,
  40         SIG_LEAVE,
  41         SIG_CLICKED,
  42         SIG_BUTTON_PRESS,
  43         SIG_BUTTON_RELEASE,
  44         SIG_KEY_PRESS,
  45         SIG_KEY_RELEASE,
  46         SIG_MOTION,
  47         NUM_SIGNALS,
  48 };
  49 static guint signals[NUM_SIGNALS];
  50
  51 void grits_object_pickdraw(GritsObject *object, GritsOpenGL *opengl, gboolean pick)
  52 {
  53         GritsObjectClass *klass = GRITS_OBJECT_GET_CLASS(object);
  54         if (!klass->draw) {
  55                 g_warning("GritsObject: draw - Unimplemented");
  56                 return;
  57         }
  58
  59         /* Skip hidden objects */
  60         if (object->hidden)
  61                 return;
  62
  63         /* Support GritsTester */
  64         if (!GRITS_IS_OPENGL(opengl)) {
  65                 g_debug("GritsObject: draw - drawing raw object");
  66                 klass->draw(object, opengl);
  67                 return;
  68         }
  69
  70         /* Calculae distance for LOD and horizon tests */
  71         GritsPoint *center = &object->center;
  72         if ((!(object->skip & GRITS_SKIP_LOD) ||
  73              !(object->skip & GRITS_SKIP_HORIZON)) &&
  74             (center->elev != -EARTH_R)) {
  75                 /* LOD test */
  76                 gdouble eye[3], obj[3];
  77                 grits_viewer_get_location(GRITS_VIEWER(opengl),
  78                                 &eye[0], &eye[1], &eye[2]);
  79                 gdouble elev = eye[2];
  80                 lle2xyz(eye[0], eye[1], eye[2],
  81                                 &eye[0], &eye[1], &eye[2]);
  82                 lle2xyz(center->lat, center->lon, center->elev,
  83                                 &obj[0], &obj[1], &obj[2]);
  84                 gdouble dist = distd(obj, eye);
  85
  86                 /* Level of detail test */
  87                 if (!(object->skip & GRITS_SKIP_LOD)
  88                                 && object->lod > 0) {
  89                         if (object->lod < dist)
  90                                 return;
  91                 }
  92
  93                 /* Horizon test */
  94                 if (!(object->skip & GRITS_SKIP_HORIZON)) {
  95                         gdouble c = EARTH_R+elev;
  96                         gdouble a = EARTH_R;
  97                         gdouble horizon = sqrt(c*c - a*a);
  98                         if (dist > horizon)
  99                                 return;
 100                 }
 101         }
 102
 103         /* Save state, draw, restore state */
 104         g_mutex_lock(opengl->sphere_lock);
 105         if (!(object->skip & GRITS_SKIP_STATE)) {
 106                 glPushAttrib(GL_ALL_ATTRIB_BITS);
 107                 glMatrixMode(GL_PROJECTION); glPushMatrix();
 108                 glMatrixMode(GL_MODELVIEW);  glPushMatrix();
 109         }
 110
 111         if (!(object->skip & GRITS_SKIP_CENTER))
 112                 grits_viewer_center_position(GRITS_VIEWER(opengl),
 113                                 object->center.lat,
 114                                 object->center.lon,
 115                                 object->center.elev);
 116
 117         if (pick && klass->pick)
 118                 klass->pick(object, opengl);
 119         else
 120                 klass->draw(object, opengl);
 121
 122         if (!(object->skip & GRITS_SKIP_STATE)) {
 123                 glPopAttrib();
 124                 glMatrixMode(GL_PROJECTION); glPopMatrix();
 125                 glMatrixMode(GL_MODELVIEW);  glPopMatrix();
 126         }
 127         g_mutex_unlock(opengl->sphere_lock);
 128 }
 129
 130 /**
 131  * grits_object_draw:
 132  * @object: the object
 133  * @opengl: the viewer the object is being displayed in
 134  *
 135  * Perform any OpenGL commands necessasairy to draw the object.
 136  *
 137  * The GL_PROJECTION and GL_MODELVIEW matricies and GL_ALL_ATTRIB_BITS will be
 138  * restored to the default state after the call to draw.
 139  */
 140 void grits_object_draw(GritsObject *object, GritsOpenGL *opengl)
 141 {
 142         grits_object_pickdraw(object, opengl, FALSE);
 143 }
 144
 145 void grits_object_hide(GritsObject *object, gboolean hidden)
 146 {
 147         GritsObjectClass *klass = GRITS_OBJECT_GET_CLASS(object);
 148         object->hidden = hidden;
 149         if (klass->hide)
 150                 klass->hide(object, hidden);
 151 }
 152
 153 void grits_object_queue_draw(GritsObject *object)
 154 {
 155         if (object->viewer)
 156                 gtk_widget_queue_draw(GTK_WIDGET(object->viewer));
 157 }
 158
 159 /* Event handling */
 160 void grits_object_pick_begin(GritsObject *object, GritsOpenGL *opengl)
 161 {
 162         object->state.picked = FALSE;
 163
 164         /* Check for connected signals */
 165         for (int i = 0; i < NUM_SIGNALS; i++) {
 166                 if (g_signal_has_handler_pending(object, signals[i], 0, FALSE)) {
 167                         /* Someone is watching, render the object _once_ */
 168                         glPushName((guint)object);
 169                         grits_object_pickdraw(object, opengl, TRUE);
 170                         glPopName();
 171                         return;
 172                 }
 173         }
 174 }
 175
 176 void grits_object_pick_pointer(GritsObject *object, double x, double y)
 177 {
 178         object->state.picked = TRUE;
 179 }
 180
 181 void grits_object_pick_end(GritsObject *object)
 182 {
 183         if (object->state.picked) {
 184                 if (!object->state.selected)
 185                         g_signal_emit(object, signals[SIG_ENTER], 0);
 186                 object->state.selected = TRUE;
 187         } else {
 188                 if (object->state.selected)
 189                         g_signal_emit(object, signals[SIG_LEAVE], 0);
 190                 object->state.selected = FALSE;
 191         }
 192 }
 193
 194 void grits_object_event(GritsObject *object, GdkEvent *event)
 195 {
 196         const int map[GDK_EVENT_LAST] = {
 197                 [GDK_BUTTON_PRESS  ] SIG_BUTTON_PRESS,
 198                 [GDK_2BUTTON_PRESS ] SIG_BUTTON_PRESS,
 199                 [GDK_3BUTTON_PRESS ] SIG_BUTTON_PRESS,
 200                 [GDK_BUTTON_RELEASE] SIG_BUTTON_RELEASE,
 201                 [GDK_KEY_PRESS     ] SIG_KEY_PRESS,
 202                 [GDK_KEY_RELEASE   ] SIG_KEY_RELEASE,
 203                 [GDK_MOTION_NOTIFY ] SIG_MOTION,
 204         };
 205         if (!object->state.selected)
 206                 return;
 207         guint sig = map[event->type];
 208
 209         /* Handle button click */
 210         if (sig == SIG_BUTTON_PRESS)
 211                 object->state.clicking = TRUE;
 212         if (sig == SIG_BUTTON_RELEASE && object->state.clicking)
 213                 g_signal_emit(object, signals[SIG_CLICKED], 0, event);
 214         if (sig == SIG_BUTTON_RELEASE || sig == SIG_MOTION)
 215                 object->state.clicking = FALSE;
 216
 217         /* Emit this signal */
 218         if (!g_signal_has_handler_pending(object, signals[sig], 0, FALSE))
 219                 return;
 220         g_signal_emit(object, signals[sig], 0, event);
 221 }
 222
 223 /* GObject stuff */
 224 G_DEFINE_ABSTRACT_TYPE(GritsObject, grits_object, G_TYPE_OBJECT);
 225 static void grits_object_init(GritsObject *object)
 226 {
 227         object->center.lat  =  0;
 228         object->center.lon  =  0;
 229         object->center.elev = -EARTH_R;
 230 }
 231
 232 static void grits_object_class_init(GritsObjectClass *klass)
 233 {
 234         GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
 235
 236         /**
 237          * GritsObject::enter:
 238          * @object: the object.
 239          *
 240          * The ::enter signal is emitted when the pointer moves over the object
 241          */
 242         signals[SIG_ENTER] = g_signal_new(
 243                         "enter",
 244                         G_TYPE_FROM_CLASS(gobject_class),
 245                         G_SIGNAL_RUN_LAST,
 246                         0,
 247                         NULL,
 248                         NULL,
 249                         g_cclosure_marshal_VOID__VOID,
 250                         G_TYPE_NONE,
 251                         0);
 252
 253         /**
 254          * GritsViewer::leave:
 255          * @object: the object.
 256          *
 257          * The ::leave signal is emitted when the pointer moves away from the
 258          * object
 259          */
 260         signals[SIG_LEAVE] = g_signal_new(
 261                         "leave",
 262                         G_TYPE_FROM_CLASS(gobject_class),
 263                         G_SIGNAL_RUN_LAST,
 264                         0,
 265                         NULL,
 266                         NULL,
 267                         g_cclosure_marshal_VOID__VOID,
 268                         G_TYPE_NONE,
 269                         0);
 270
 271         /**
 272          * GritsViewer::clicked:
 273          * @object: the object.
 274          *
 275          * The ::clicked signal is emitted when the user clicks on the object
 276          */
 277         signals[SIG_CLICKED] = g_signal_new(
 278                         "clicked",
 279                         G_TYPE_FROM_CLASS(gobject_class),
 280                         G_SIGNAL_RUN_LAST,
 281                         0,
 282                         NULL,
 283                         NULL,
 284                         g_cclosure_marshal_VOID__VOID,
 285                         G_TYPE_NONE,
 286                         0);
 287
 288         /**
 289          * GritsViewer::button-press:
 290          * @object: the object.
 291          * @event:  the GdkEventButton which triggered this signal
 292          *
 293          * The ::button-press signal is emitted when a button (typically from a
 294          * mouse) is pressed.
 295          */
 296         signals[SIG_BUTTON_PRESS] = g_signal_new(
 297                         "button-press",
 298                         G_TYPE_FROM_CLASS(gobject_class),
 299                         G_SIGNAL_RUN_LAST,
 300                         0,
 301                         NULL,
 302                         NULL,
 303                         g_cclosure_marshal_VOID__POINTER,
 304                         G_TYPE_NONE,
 305                         1,
 306                         G_TYPE_POINTER);
 307
 308         /**
 309          * GritsViewer::button-release:
 310          * @object: the object.
 311          * @event:  the GdkEventButton which triggered this signal
 312          *
 313          * The ::button-release signal is emitted when a button (typically from
 314          * a mouse) is released.
 315          */
 316         signals[SIG_BUTTON_RELEASE] = g_signal_new(
 317                         "button-release",
 318                         G_TYPE_FROM_CLASS(gobject_class),
 319                         G_SIGNAL_RUN_LAST,
 320                         0,
 321                         NULL,
 322                         NULL,
 323                         g_cclosure_marshal_VOID__POINTER,
 324                         G_TYPE_NONE,
 325                         1,
 326                         G_TYPE_POINTER);
 327
 328         /**
 329          * GritsViewer::key-press:
 330          * @object: the object.
 331          * @event:  the GdkEventKey which triggered this signal
 332          *
 333          * The ::key-press signal is emitted when a key is pressed.
 334          */
 335         signals[SIG_KEY_PRESS] = g_signal_new(
 336                         "key-press",
 337                         G_TYPE_FROM_CLASS(gobject_class),
 338                         G_SIGNAL_RUN_LAST,
 339                         0,
 340                         NULL,
 341                         NULL,
 342                         g_cclosure_marshal_VOID__POINTER,
 343                         G_TYPE_NONE,
 344                         1,
 345                         G_TYPE_POINTER);
 346
 347         /**
 348          * GritsViewer::key-release:
 349          * @object: the object.
 350          * @event:  the GdkEventKey which triggered this signal
 351          *
 352          * The ::key-release signal is emitted when a key is released.
 353          */
 354         signals[SIG_KEY_RELEASE] = g_signal_new(
 355                         "key-release",
 356                         G_TYPE_FROM_CLASS(gobject_class),
 357                         G_SIGNAL_RUN_LAST,
 358                         0,
 359                         NULL,
 360                         NULL,
 361                         g_cclosure_marshal_VOID__POINTER,
 362                         G_TYPE_NONE,
 363                         1,
 364                         G_TYPE_POINTER);
 365
 366         /**
 367          * GritsViewer::motion:
 368          * @object: the object.
 369          * @event:  the GdkEventMotion which triggered this signal
 370          *
 371          * The ::motion signal is emitted the pointer moves over the object
 372          */
 373         signals[SIG_MOTION] = g_signal_new(
 374                         "motion",
 375                         G_TYPE_FROM_CLASS(gobject_class),
 376                         G_SIGNAL_RUN_LAST,
 377                         0,
 378                         NULL,
 379                         NULL,
 380                         g_cclosure_marshal_VOID__POINTER,
 381                         G_TYPE_NONE,
 382                         1,
 383                         G_TYPE_POINTER);
 384 }