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 this group's 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
 122                                                      << " intersect = "
 123                                                      << draw
 124                                                      << " @ "
 125                                                      << _position
 126                                                      << endl;
 127                                         }
 128                                 }
 129 #endif
 130
 131                                 (*i)->render (area, context);
 132                                 ++render_count;
 133                         }
 134
 135                 } else {
 136
 137 #ifdef CANVAS_DEBUG
 138                         if (DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
 139                                 cerr << string_compose ("%1skip render of %2 %3, no intersection\n", _canvas->render_indent(), (*i)->whatami(),
 140                                                         (*i)->name);
 141                         }
 142 #endif
 143
 144                 }
 145         }
 146
 147         --render_depth;
 148 }
 149
 150 void
 151 Group::compute_bounding_box () const
 152 {
 153         Rect bbox;
 154         bool have_one = false;
 155
 156         for (list<Item*>::const_iterator i = _items.begin(); i != _items.end(); ++i) {
 157
 158                 boost::optional<Rect> item_bbox = (*i)->bounding_box ();
 159
 160                 if (!item_bbox) {
 161                         continue;
 162                 }
 163
 164                 Rect group_bbox = (*i)->item_to_parent (item_bbox.get ());
 165                 if (have_one) {
 166                         bbox = bbox.extend (group_bbox);
 167                 } else {
 168                         bbox = group_bbox;
 169                         have_one = true;
 170                 }
 171         }
 172
 173         if (!have_one) {
 174                 _bounding_box = boost::optional<Rect> ();
 175         } else {
 176                 _bounding_box = bbox;
 177         }
 178
 179         _bounding_box_dirty = false;
 180 }
 181
 182 void
 183 Group::add (Item* i)
 184 {
 185         /* XXX should really notify canvas about this */
 186
 187         _items.push_back (i);
 188         invalidate_lut ();
 189         _bounding_box_dirty = true;
 190
 191
 192 }
 193
 194 void
 195 Group::remove (Item* i)
 196 {
 197
 198         if (i->parent() != this) {
 199                 return;
 200         }
 201
 202         /* we cannot call bounding_box() here because that will iterate over
 203            _items, one of which (the argument, i) may be in the middle of
 204            deletion, making it impossible to call compute_bounding_box()
 205            on it.
 206         */
 207
 208         if (_bounding_box) {
 209                 _pre_change_bounding_box = _bounding_box;
 210         } else {
 211                 _pre_change_bounding_box = Rect();
 212         }
 213
 214         i->unparent ();
 215         _items.remove (i);
 216         invalidate_lut ();
 217         _bounding_box_dirty = true;
 218
 219         end_change ();
 220 }
 221
 222 void
 223 Group::clear (bool with_delete)
 224 {
 225         begin_change ();
 226
 227         clear_items (with_delete);
 228
 229         invalidate_lut ();
 230         _bounding_box_dirty = true;
 231
 232         end_change ();
 233 }
 234
 235 void
 236 Group::clear_items (bool with_delete)
 237 {
 238         for (list<Item*>::iterator i = _items.begin(); i != _items.end(); ) {
 239
 240                 list<Item*>::iterator tmp = i;
 241                 Item *item = *i;
 242
 243                 ++tmp;
 244
 245                 /* remove from list before doing anything else, because we
 246                  * don't want to find the item in _items during any activity
 247                  * driven by unparent-ing or deletion.
 248                  */
 249
 250                 _items.erase (i);
 251                 item->unparent ();
 252
 253                 if (with_delete) {
 254                         delete item;
 255                 }
 256
 257                 i = tmp;
 258         }
 259 }
 260
 261 void
 262 Group::raise_child_to_top (Item* i)
 263 {
 264         if (!_items.empty()) {
 265                 if (_items.back() == i) {
 266                         return;
 267                 }
 268         }
 269
 270         _items.remove (i);
 271         _items.push_back (i);
 272         invalidate_lut ();
 273 }
 274
 275 void
 276 Group::raise_child (Item* i, int levels)
 277 {
 278         list<Item*>::iterator j = find (_items.begin(), _items.end(), i);
 279         assert (j != _items.end ());
 280
 281         ++j;
 282         _items.remove (i);
 283
 284         while (levels > 0 && j != _items.end ()) {
 285                 ++j;
 286                 --levels;
 287         }
 288
 289         _items.insert (j, i);
 290         invalidate_lut ();
 291 }
 292
 293 void
 294 Group::lower_child_to_bottom (Item* i)
 295 {
 296         if (!_items.empty()) {
 297                 if (_items.front() == i) {
 298                         return;
 299                 }
 300         }
 301         _items.remove (i);
 302         _items.push_front (i);
 303         invalidate_lut ();
 304 }
 305
 306 void
 307 Group::ensure_lut () const
 308 {
 309         if (!_lut) {
 310                 _lut = new DumbLookupTable (*this);
 311         }
 312 }
 313
 314 void
 315 Group::invalidate_lut () const
 316 {
 317         delete _lut;
 318         _lut = 0;
 319 }
 320
 321 void
 322 Group::child_changed ()
 323 {
 324         invalidate_lut ();
 325         _bounding_box_dirty = true;
 326
 327         if (_parent) {
 328                 _parent->child_changed ();
 329         }
 330 }
 331
 332 void
 333 Group::add_items_at_point (Duple const point, vector<Item const *>& items) const
 334 {
 335         boost::optional<Rect> const bbox = bounding_box ();
 336
 337         /* Point is in canvas coordinate system */
 338
 339         if (!bbox || !item_to_canvas (bbox.get()).contains (point)) {
 340                 return;
 341         }
 342
 343         /* now recurse and add any items within our group that contain point */
 344
 345         ensure_lut ();
 346         vector<Item*> our_items = _lut->items_at_point (point);
 347
 348         if (!our_items.empty()) {
 349                 /* this adds this group itself to the list of items at point */
 350                 Item::add_items_at_point (point, items);
 351         }
 352
 353         for (vector<Item*>::iterator i = our_items.begin(); i != our_items.end(); ++i) {
 354                 (*i)->add_items_at_point (point, items);
 355         }
 356 }
 357
 358 void
 359 Group::dump (ostream& o) const
 360 {
 361 #ifdef CANVAS_DEBUG
 362         o << _canvas->indent();
 363         o << "Group " << this << " [" << name << ']';
 364         o << " @ " << position();
 365         o << " Items: " << _items.size();
 366         o << " Visible ? " << _visible;
 367
 368         boost::optional<Rect> bb = bounding_box();
 369
 370         if (bb) {
 371                 o << endl << _canvas->indent() << "  bbox: " << bb.get();
 372                 o << endl << _canvas->indent() << "  CANVAS bbox: " << item_to_canvas (bb.get());
 373         } else {
 374                 o << "  bbox unset";
 375         }
 376
 377         o << endl;
 378 #endif
 379
 380         ArdourCanvas::dump_depth++;
 381
 382         for (list<Item*>::const_iterator i = _items.begin(); i != _items.end(); ++i) {
 383                 o << **i;
 384         }
 385
 386         ArdourCanvas::dump_depth--;
 387 }