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