libs/canvas/group.cc

   1 /*
   2     Copyright (C) 2011-2013 Paul Davis
   3     Author: Carl Hetherington <cth@carlh.net>
   4
   5     This program is free software; you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation; either version 2 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14
  15     You should have received a copy of the GNU General Public License
  16     along with this program; if not, write to the Free Software
  17     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18 */
  19
  20 #include <iostream>
  21 #include <cairomm/context.h>
  22
  23 #include "pbd/stacktrace.h"
  24 #include "pbd/compose.h"
  25
  26 #include "canvas/group.h"
  27 #include "canvas/types.h"
  28 #include "canvas/debug.h"
  29 #include "canvas/item.h"
  30 #include "canvas/canvas.h"
  31
  32 using namespace std;
  33 using namespace ArdourCanvas;
  34
  35 int Group::default_items_per_cell = 64;
  36
  37
  38 Group::Group (Canvas* canvas)
  39         : Item (canvas)
  40         , _lut (0)
  41 {
  42
  43 }
  44
  45 Group::Group (Group* parent)
  46         : Item (parent)
  47         , _lut (0)
  48 {
  49
  50 }
  51
  52 Group::Group (Group* parent, Duple position)
  53         : Item (parent, position)
  54         , _lut (0)
  55 {
  56
  57 }
  58
  59 Group::~Group ()
  60 {
  61         clear_items (true);
  62 }
  63
  64 /** @param area Area to draw in window coordinates.
  65  *  @param context Context, set up with its origin at this group's position.
  66  */
  67 void
  68 Group::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) const
  69 {
  70         ensure_lut ();
  71         vector<Item*> items = _lut->get (area);
  72
  73 #ifdef CANVAS_DEBUG
  74         if (DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
  75                 cerr << string_compose ("%1GROUP %2 @ %7 render %5 @ %6 %3 items out of %4\n",
  76                                         _canvas->render_indent(), (name.empty() ? string ("[unnamed]") : name), items.size(), _items.size(), area, _position, this);
  77         }
  78 #endif
  79
  80         ++render_depth;
  81
  82         for (vector<Item*>::const_iterator i = items.begin(); i != items.end(); ++i) {
  83
  84                 if (!(*i)->visible ()) {
  85 #ifdef CANVAS_DEBUG
  86                         if (DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
  87                                 cerr << _canvas->render_indent() << "Item " << (*i)->whatami() << " [" << (*i)->name << "] invisible - skipped\n";
  88                         }
  89 #endif
  90                         continue;
  91                 }
  92
  93                 boost::optional<Rect> item_bbox = (*i)->bounding_box ();
  94
  95                 if (!item_bbox) {
  96 #ifdef CANVAS_DEBUG
  97                         if (DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
  98                                 cerr << _canvas->render_indent() << "Item " << (*i)->whatami() << " [" << (*i)->name << "] empty - skipped\n";
  99                         }
 100 #endif
 101                         continue;
 102                 }
 103
 104                 Rect item = (*i)->item_to_window (item_bbox.get());
 105                 boost::optional<Rect> d = item.intersection (area);
 106
 107                 if (d) {
 108                         Rect draw = d.get();
 109                         if (draw.width() && draw.height()) {
 110 #ifdef CANVAS_DEBUG
 111                                 if (DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
 112                                         if (dynamic_cast<Group*>(*i) == 0) {
 113                                                 cerr << _canvas->render_indent() << "render "
 114                                                      << ' '
 115                                                      << (*i)
 116                                                      << ' '
 117                                                      << (*i)->whatami()
 118                                                      << ' '
 119                                                      << (*i)->name
 120                                                      << " item "
 121                                                      << item_bbox.get()
 122                                                      << " window = "
 123                                                      << item
 124                                                      << " intersect = "
 125                                                      << draw
 126                                                      << " @ "
 127                                                      << _position
 128                                                      << endl;
 129                                         }
 130                                 }
 131 #endif
 132
 133                                 (*i)->render (area, context);
 134                                 ++render_count;
 135                         }
 136
 137                 } else {
 138
 139 #ifdef CANVAS_DEBUG
 140                         if (DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
 141                                 cerr << string_compose ("%1skip render of %2 %3, no intersection between %4 and %5\n", _canvas->render_indent(), (*i)->whatami(),
 142                                                         (*i)->name, item, area);
 143                         }
 144 #endif
 145
 146                 }
 147         }
 148
 149         --render_depth;
 150 }
 151
 152 void
 153 Group::scroll_to (Duple const& d)
 154 {
 155         Item::scroll_to (d);
 156
 157         for (list<Item*>::iterator i = _items.begin(); i != _items.end(); ++i) {
 158                 (*i)->scroll_to (d);
 159         }
 160 }
 161
 162 void
 163 Group::compute_bounding_box () const
 164 {
 165         Rect bbox;
 166         bool have_one = false;
 167
 168         for (list<Item*>::const_iterator i = _items.begin(); i != _items.end(); ++i) {
 169
 170                 boost::optional<Rect> item_bbox = (*i)->bounding_box ();
 171
 172                 if (!item_bbox) {
 173                         continue;
 174                 }
 175
 176                 Rect group_bbox = (*i)->item_to_parent (item_bbox.get ());
 177                 if (have_one) {
 178                         bbox = bbox.extend (group_bbox);
 179                 } else {
 180                         bbox = group_bbox;
 181                         have_one = true;
 182                 }
 183         }
 184
 185         if (!have_one) {
 186                 _bounding_box = boost::optional<Rect> ();
 187         } else {
 188                 _bounding_box = bbox;
 189         }
 190
 191         _bounding_box_dirty = false;
 192 }
 193
 194 void
 195 Group::add (Item* i)
 196 {
 197         /* XXX should really notify canvas about this */
 198
 199         _items.push_back (i);
 200         invalidate_lut ();
 201         _bounding_box_dirty = true;
 202
 203
 204 }
 205
 206 void
 207 Group::remove (Item* i)
 208 {
 209
 210         if (i->parent() != this) {
 211                 return;
 212         }
 213
 214         /* we cannot call bounding_box() here because that will iterate over
 215            _items, one of which (the argument, i) may be in the middle of
 216            deletion, making it impossible to call compute_bounding_box()
 217            on it.
 218         */
 219
 220         if (_bounding_box) {
 221                 _pre_change_bounding_box = _bounding_box;
 222         } else {
 223                 _pre_change_bounding_box = Rect();
 224         }
 225
 226         i->unparent ();
 227         _items.remove (i);
 228         invalidate_lut ();
 229         _bounding_box_dirty = true;
 230
 231         end_change ();
 232 }
 233
 234 void
 235 Group::clear (bool with_delete)
 236 {
 237         begin_change ();
 238
 239         clear_items (with_delete);
 240
 241         invalidate_lut ();
 242         _bounding_box_dirty = true;
 243
 244         end_change ();
 245 }
 246
 247 void
 248 Group::clear_items (bool with_delete)
 249 {
 250         for (list<Item*>::iterator i = _items.begin(); i != _items.end(); ) {
 251
 252                 list<Item*>::iterator tmp = i;
 253                 Item *item = *i;
 254
 255                 ++tmp;
 256
 257                 /* remove from list before doing anything else, because we
 258                  * don't want to find the item in _items during any activity
 259                  * driven by unparent-ing or deletion.
 260                  */
 261
 262                 _items.erase (i);
 263                 item->unparent ();
 264
 265                 if (with_delete) {
 266                         delete item;
 267                 }
 268
 269                 i = tmp;
 270         }
 271 }
 272
 273 void
 274 Group::raise_child_to_top (Item* i)
 275 {
 276         if (!_items.empty()) {
 277                 if (_items.back() == i) {
 278                         return;
 279                 }
 280         }
 281
 282         _items.remove (i);
 283         _items.push_back (i);
 284         invalidate_lut ();
 285 }
 286
 287 void
 288 Group::raise_child (Item* i, int levels)
 289 {
 290         list<Item*>::iterator j = find (_items.begin(), _items.end(), i);
 291         assert (j != _items.end ());
 292
 293         ++j;
 294         _items.remove (i);
 295
 296         while (levels > 0 && j != _items.end ()) {
 297                 ++j;
 298                 --levels;
 299         }
 300
 301         _items.insert (j, i);
 302         invalidate_lut ();
 303 }
 304
 305 void
 306 Group::lower_child_to_bottom (Item* i)
 307 {
 308         if (!_items.empty()) {
 309                 if (_items.front() == i) {
 310                         return;
 311                 }
 312         }
 313         _items.remove (i);
 314         _items.push_front (i);
 315         invalidate_lut ();
 316 }
 317
 318 void
 319 Group::ensure_lut () const
 320 {
 321         if (!_lut) {
 322                 _lut = new DumbLookupTable (*this);
 323         }
 324 }
 325
 326 void
 327 Group::invalidate_lut () const
 328 {
 329         delete _lut;
 330         _lut = 0;
 331 }
 332
 333 void
 334 Group::child_changed ()
 335 {
 336         invalidate_lut ();
 337         _bounding_box_dirty = true;
 338
 339         if (_parent) {
 340                 _parent->child_changed ();
 341         }
 342 }
 343
 344 void
 345 Group::add_items_at_point (Duple const point, vector<Item const *>& items) const
 346 {
 347         boost::optional<Rect> const bbox = bounding_box ();
 348
 349         /* Point is in window coordinate system */
 350
 351         if (!bbox || !item_to_window (bbox.get()).contains (point)) {
 352                 return;
 353         }
 354
 355         /* now recurse and add any items within our group that contain point */
 356
 357         ensure_lut ();
 358         vector<Item*> our_items = _lut->items_at_point (point);
 359
 360         if (!our_items.empty()) {
 361                 /* this adds this group itself to the list of items at point */
 362                 Item::add_items_at_point (point, items);
 363         }
 364
 365         for (vector<Item*>::iterator i = our_items.begin(); i != our_items.end(); ++i) {
 366                 (*i)->add_items_at_point (point, items);
 367         }
 368 }
 369
 370 void
 371 Group::dump (ostream& o) const
 372 {
 373 #ifdef CANVAS_DEBUG
 374         o << _canvas->indent();
 375         o << "Group " << this << " [" << name << ']';
 376         o << " @ " << position();
 377         o << " Items: " << _items.size();
 378         o << " Visible ? " << _visible;
 379
 380         boost::optional<Rect> bb = bounding_box();
 381
 382         if (bb) {
 383                 o << endl << _canvas->indent() << "  bbox: " << bb.get();
 384                 o << endl << _canvas->indent() << "  CANVAS bbox: " << item_to_canvas (bb.get());
 385         } else {
 386                 o << "  bbox unset";
 387         }
 388
 389         o << endl;
 390 #endif
 391
 392         ArdourCanvas::dump_depth++;
 393
 394         for (list<Item*>::const_iterator i = _items.begin(); i != _items.end(); ++i) {
 395                 o << **i;
 396         }
 397
 398         ArdourCanvas::dump_depth--;
 399 }