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