src/wx/timeline.cc

   1 /*
   2     Copyright (C) 2013-2014 Carl Hetherington <cth@carlh.net>
   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 2 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, write to the Free Software
  16     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17
  18 */
  19
  20 #include <list>
  21 #include <wx/graphics.h>
  22 #include <boost/weak_ptr.hpp>
  23 #include "lib/film.h"
  24 #include "lib/playlist.h"
  25 #include "film_editor.h"
  26 #include "timeline.h"
  27 #include "wx_util.h"
  28
  29 using std::list;
  30 using std::cout;
  31 using std::max;
  32 using boost::shared_ptr;
  33 using boost::weak_ptr;
  34 using boost::dynamic_pointer_cast;
  35 using boost::bind;
  36 using boost::optional;
  37
  38 /** @class View
  39  *  @brief Parent class for components of the timeline (e.g. a piece of content or an axis).
  40  */
  41 class View : public boost::noncopyable
  42 {
  43 public:
  44         View (Timeline& t)
  45                 : _timeline (t)
  46         {
  47
  48         }
  49
  50         virtual ~View () {}
  51
  52         void paint (wxGraphicsContext* g)
  53         {
  54                 _last_paint_bbox = bbox ();
  55                 do_paint (g);
  56         }
  57
  58         void force_redraw ()
  59         {
  60                 _timeline.force_redraw (_last_paint_bbox);
  61                 _timeline.force_redraw (bbox ());
  62         }
  63
  64         virtual dcpomatic::Rect<int> bbox () const = 0;
  65
  66 protected:
  67         virtual void do_paint (wxGraphicsContext *) = 0;
  68
  69         int time_x (DCPTime t) const
  70         {
  71                 return _timeline.tracks_position().x + t.seconds() * _timeline.pixels_per_second().get_value_or (0);
  72         }
  73
  74         Timeline& _timeline;
  75
  76 private:
  77         dcpomatic::Rect<int> _last_paint_bbox;
  78 };
  79
  80
  81 /** @class ContentView
  82  *  @brief Parent class for views of pieces of content.
  83  */
  84 class ContentView : public View
  85 {
  86 public:
  87         ContentView (Timeline& tl, shared_ptr<Content> c)
  88                 : View (tl)
  89                 , _content (c)
  90                 , _selected (false)
  91         {
  92                 _content_connection = c->Changed.connect (bind (&ContentView::content_changed, this, _2, _3));
  93         }
  94
  95         dcpomatic::Rect<int> bbox () const
  96         {
  97                 assert (_track);
  98
  99                 shared_ptr<const Film> film = _timeline.film ();
 100                 shared_ptr<const Content> content = _content.lock ();
 101                 if (!film || !content) {
 102                         return dcpomatic::Rect<int> ();
 103                 }
 104
 105                 return dcpomatic::Rect<int> (
 106                         time_x (content->position ()) - 8,
 107                         y_pos (_track.get()) - 8,
 108                         content->length_after_trim().seconds() * _timeline.pixels_per_second().get_value_or(0) + 16,
 109                         _timeline.track_height() + 16
 110                         );
 111         }
 112
 113         void set_selected (bool s) {
 114                 _selected = s;
 115                 force_redraw ();
 116         }
 117
 118         bool selected () const {
 119                 return _selected;
 120         }
 121
 122         shared_ptr<Content> content () const {
 123                 return _content.lock ();
 124         }
 125
 126         void set_track (int t) {
 127                 _track = t;
 128         }
 129
 130         void unset_track () {
 131                 _track = boost::optional<int> ();
 132         }
 133
 134         optional<int> track () const {
 135                 return _track;
 136         }
 137
 138         virtual wxString type () const = 0;
 139         virtual wxColour colour () const = 0;
 140
 141 private:
 142
 143         void do_paint (wxGraphicsContext* gc)
 144         {
 145                 assert (_track);
 146
 147                 shared_ptr<const Film> film = _timeline.film ();
 148                 shared_ptr<const Content> cont = content ();
 149                 if (!film || !cont) {
 150                         return;
 151                 }
 152
 153                 DCPTime const position = cont->position ();
 154                 DCPTime const len = cont->length_after_trim ();
 155
 156                 wxColour selected (colour().Red() / 2, colour().Green() / 2, colour().Blue() / 2);
 157
 158                 gc->SetPen (*wxBLACK_PEN);
 159
 160                 gc->SetPen (*wxThePenList->FindOrCreatePen (wxColour (0, 0, 0), 4, wxPENSTYLE_SOLID));
 161                 if (_selected) {
 162                         gc->SetBrush (*wxTheBrushList->FindOrCreateBrush (selected, wxBRUSHSTYLE_SOLID));
 163                 } else {
 164                         gc->SetBrush (*wxTheBrushList->FindOrCreateBrush (colour(), wxBRUSHSTYLE_SOLID));
 165                 }
 166
 167                 wxGraphicsPath path = gc->CreatePath ();
 168                 path.MoveToPoint    (time_x (position),       y_pos (_track.get()) + 4);
 169                 path.AddLineToPoint (time_x (position + len), y_pos (_track.get()) + 4);
 170                 path.AddLineToPoint (time_x (position + len), y_pos (_track.get() + 1) - 4);
 171                 path.AddLineToPoint (time_x (position),       y_pos (_track.get() + 1) - 4);
 172                 path.AddLineToPoint (time_x (position),       y_pos (_track.get()) + 4);
 173                 gc->StrokePath (path);
 174                 gc->FillPath (path);
 175
 176                 wxString name = wxString::Format (wxT ("%s [%s]"), std_to_wx (cont->path_summary()).data(), type().data());
 177                 wxDouble name_width;
 178                 wxDouble name_height;
 179                 wxDouble name_descent;
 180                 wxDouble name_leading;
 181                 gc->GetTextExtent (name, &name_width, &name_height, &name_descent, &name_leading);
 182
 183                 gc->Clip (wxRegion (time_x (position), y_pos (_track.get()), len.seconds() * _timeline.pixels_per_second().get_value_or(0), _timeline.track_height()));
 184                 gc->DrawText (name, time_x (position) + 12, y_pos (_track.get() + 1) - name_height - 4);
 185                 gc->ResetClip ();
 186         }
 187
 188         int y_pos (int t) const
 189         {
 190                 return _timeline.tracks_position().y + t * _timeline.track_height();
 191         }
 192
 193         void content_changed (int p, bool frequent)
 194         {
 195                 ensure_ui_thread ();
 196
 197                 if (p == ContentProperty::POSITION || p == ContentProperty::LENGTH) {
 198                         force_redraw ();
 199                 }
 200
 201                 if (!frequent) {
 202                         _timeline.setup_pixels_per_second ();
 203                         _timeline.Refresh ();
 204                 }
 205         }
 206
 207         boost::weak_ptr<Content> _content;
 208         optional<int> _track;
 209         bool _selected;
 210
 211         boost::signals2::scoped_connection _content_connection;
 212 };
 213
 214 class AudioContentView : public ContentView
 215 {
 216 public:
 217         AudioContentView (Timeline& tl, shared_ptr<Content> c)
 218                 : ContentView (tl, c)
 219         {}
 220
 221 private:
 222         wxString type () const
 223         {
 224                 return _("audio");
 225         }
 226
 227         wxColour colour () const
 228         {
 229                 return wxColour (149, 121, 232, 255);
 230         }
 231 };
 232
 233 class VideoContentView : public ContentView
 234 {
 235 public:
 236         VideoContentView (Timeline& tl, shared_ptr<Content> c)
 237                 : ContentView (tl, c)
 238         {}
 239
 240 private:
 241
 242         wxString type () const
 243         {
 244                 if (dynamic_pointer_cast<FFmpegContent> (content ())) {
 245                         return _("video");
 246                 } else {
 247                         return _("still");
 248                 }
 249         }
 250
 251         wxColour colour () const
 252         {
 253                 return wxColour (242, 92, 120, 255);
 254         }
 255 };
 256
 257 class SubtitleContentView : public ContentView
 258 {
 259 public:
 260         SubtitleContentView (Timeline& tl, shared_ptr<Content> c)
 261                 : ContentView (tl, c)
 262         {}
 263
 264 private:
 265         wxString type () const
 266         {
 267                 return _("subtitles");
 268         }
 269
 270         wxColour colour () const
 271         {
 272                 return wxColour (163, 255, 154, 255);
 273         }
 274 };
 275
 276 class TimeAxisView : public View
 277 {
 278 public:
 279         TimeAxisView (Timeline& tl, int y)
 280                 : View (tl)
 281                 , _y (y)
 282         {}
 283
 284         dcpomatic::Rect<int> bbox () const
 285         {
 286                 return dcpomatic::Rect<int> (0, _y - 4, _timeline.width(), 24);
 287         }
 288
 289         void set_y (int y)
 290         {
 291                 _y = y;
 292                 force_redraw ();
 293         }
 294
 295 private:
 296
 297         void do_paint (wxGraphicsContext* gc)
 298         {
 299                 if (!_timeline.pixels_per_second()) {
 300                         return;
 301                 }
 302
 303                 double const pps = _timeline.pixels_per_second().get ();
 304
 305                 gc->SetPen (*wxThePenList->FindOrCreatePen (wxColour (0, 0, 0), 1, wxPENSTYLE_SOLID));
 306
 307                 double mark_interval = rint (128 / pps);
 308                 if (mark_interval > 5) {
 309                         mark_interval -= int (rint (mark_interval)) % 5;
 310                 }
 311                 if (mark_interval > 10) {
 312                         mark_interval -= int (rint (mark_interval)) % 10;
 313                 }
 314                 if (mark_interval > 60) {
 315                         mark_interval -= int (rint (mark_interval)) % 60;
 316                 }
 317                 if (mark_interval > 3600) {
 318                         mark_interval -= int (rint (mark_interval)) % 3600;
 319                 }
 320
 321                 if (mark_interval < 1) {
 322                         mark_interval = 1;
 323                 }
 324
 325                 wxGraphicsPath path = gc->CreatePath ();
 326                 path.MoveToPoint (_timeline.x_offset(), _y);
 327                 path.AddLineToPoint (_timeline.width(), _y);
 328                 gc->StrokePath (path);
 329
 330                 /* Time in seconds */
 331                 DCPTime t;
 332                 while ((t.seconds() * pps) < _timeline.width()) {
 333                         wxGraphicsPath path = gc->CreatePath ();
 334                         path.MoveToPoint (time_x (t), _y - 4);
 335                         path.AddLineToPoint (time_x (t), _y + 4);
 336                         gc->StrokePath (path);
 337
 338                         double tc = t.seconds ();
 339                         int const h = tc / 3600;
 340                         tc -= h * 3600;
 341                         int const m = tc / 60;
 342                         tc -= m * 60;
 343                         int const s = tc;
 344
 345                         wxString str = wxString::Format (wxT ("%02d:%02d:%02d"), h, m, s);
 346                         wxDouble str_width;
 347                         wxDouble str_height;
 348                         wxDouble str_descent;
 349                         wxDouble str_leading;
 350                         gc->GetTextExtent (str, &str_width, &str_height, &str_descent, &str_leading);
 351
 352                         int const tx = _timeline.x_offset() + t.seconds() * pps;
 353                         if ((tx + str_width) < _timeline.width()) {
 354                                 gc->DrawText (str, time_x (t), _y + 16);
 355                         }
 356
 357                         t += DCPTime::from_seconds (mark_interval);
 358                 }
 359         }
 360
 361 private:
 362         int _y;
 363 };
 364
 365
 366 Timeline::Timeline (wxWindow* parent, FilmEditor* ed, shared_ptr<Film> film)
 367         : wxPanel (parent, wxID_ANY, wxDefaultPosition, wxDefaultSize, wxFULL_REPAINT_ON_RESIZE)
 368         , _film_editor (ed)
 369         , _film (film)
 370         , _time_axis_view (new TimeAxisView (*this, 32))
 371         , _tracks (0)
 372         , _left_down (false)
 373         , _down_view_position (0)
 374         , _first_move (false)
 375         , _menu (this)
 376         , _snap (true)
 377 {
 378 #ifndef __WXOSX__
 379         SetDoubleBuffered (true);
 380 #endif
 381
 382         Bind (wxEVT_PAINT,      boost::bind (&Timeline::paint,       this));
 383         Bind (wxEVT_LEFT_DOWN,  boost::bind (&Timeline::left_down,   this, _1));
 384         Bind (wxEVT_LEFT_UP,    boost::bind (&Timeline::left_up,     this, _1));
 385         Bind (wxEVT_RIGHT_DOWN, boost::bind (&Timeline::right_down,  this, _1));
 386         Bind (wxEVT_MOTION,     boost::bind (&Timeline::mouse_moved, this, _1));
 387         Bind (wxEVT_SIZE,       boost::bind (&Timeline::resized,     this));
 388
 389         playlist_changed ();
 390
 391         SetMinSize (wxSize (640, tracks() * track_height() + 96));
 392
 393         _playlist_changed_connection = film->playlist()->Changed.connect (bind (&Timeline::playlist_changed, this));
 394         _playlist_content_changed_connection = film->playlist()->ContentChanged.connect (bind (&Timeline::playlist_content_changed, this, _2));
 395 }
 396
 397 void
 398 Timeline::paint ()
 399 {
 400         wxPaintDC dc (this);
 401
 402         wxGraphicsContext* gc = wxGraphicsContext::Create (dc);
 403         if (!gc) {
 404                 return;
 405         }
 406
 407         gc->SetFont (gc->CreateFont (*wxNORMAL_FONT));
 408
 409         for (ViewList::iterator i = _views.begin(); i != _views.end(); ++i) {
 410                 (*i)->paint (gc);
 411         }
 412
 413         delete gc;
 414 }
 415
 416 void
 417 Timeline::playlist_changed ()
 418 {
 419         ensure_ui_thread ();
 420
 421         shared_ptr<const Film> fl = _film.lock ();
 422         if (!fl) {
 423                 return;
 424         }
 425
 426         _views.clear ();
 427         _views.push_back (_time_axis_view);
 428
 429         ContentList content = fl->playlist()->content ();
 430
 431         for (ContentList::iterator i = content.begin(); i != content.end(); ++i) {
 432                 if (dynamic_pointer_cast<VideoContent> (*i)) {
 433                         _views.push_back (shared_ptr<View> (new VideoContentView (*this, *i)));
 434                 }
 435                 if (dynamic_pointer_cast<AudioContent> (*i)) {
 436                         _views.push_back (shared_ptr<View> (new AudioContentView (*this, *i)));
 437                 }
 438                 if (dynamic_pointer_cast<SubtitleContent> (*i)) {
 439                         _views.push_back (shared_ptr<View> (new SubtitleContentView (*this, *i)));
 440                 }
 441         }
 442
 443         assign_tracks ();
 444         setup_pixels_per_second ();
 445         Refresh ();
 446 }
 447
 448 void
 449 Timeline::playlist_content_changed (int property)
 450 {
 451         ensure_ui_thread ();
 452
 453         if (property == ContentProperty::POSITION) {
 454                 assign_tracks ();
 455                 setup_pixels_per_second ();
 456                 Refresh ();
 457         }
 458 }
 459
 460 void
 461 Timeline::assign_tracks ()
 462 {
 463         for (ViewList::iterator i = _views.begin(); i != _views.end(); ++i) {
 464                 shared_ptr<ContentView> c = dynamic_pointer_cast<ContentView> (*i);
 465                 if (c) {
 466                         c->unset_track ();
 467                 }
 468         }
 469
 470         for (ViewList::iterator i = _views.begin(); i != _views.end(); ++i) {
 471                 shared_ptr<ContentView> cv = dynamic_pointer_cast<ContentView> (*i);
 472                 if (!cv) {
 473                         continue;
 474                 }
 475
 476                 shared_ptr<Content> content = cv->content();
 477
 478                 int t = 0;
 479                 while (true) {
 480                         ViewList::iterator j = _views.begin();
 481                         while (j != _views.end()) {
 482                                 shared_ptr<ContentView> test = dynamic_pointer_cast<ContentView> (*j);
 483                                 if (!test) {
 484                                         ++j;
 485                                         continue;
 486                                 }
 487
 488                                 shared_ptr<Content> test_content = test->content();
 489
 490                                 if (test && test->track() && test->track().get() == t) {
 491                                         bool const no_overlap =
 492                                                 (content->position() < test_content->position() && content->end() < test_content->position()) ||
 493                                                 (content->position() > test_content->end()      && content->end() > test_content->end());
 494
 495                                         if (!no_overlap) {
 496                                                 /* we have an overlap on track `t' */
 497                                                 ++t;
 498                                                 break;
 499                                         }
 500                                 }
 501
 502                                 ++j;
 503                         }
 504
 505                         if (j == _views.end ()) {
 506                                 /* no overlap on `t' */
 507                                 break;
 508                         }
 509                 }
 510
 511                 cv->set_track (t);
 512                 _tracks = max (_tracks, t + 1);
 513         }
 514
 515         _time_axis_view->set_y (tracks() * track_height() + 32);
 516 }
 517
 518 int
 519 Timeline::tracks () const
 520 {
 521         return _tracks;
 522 }
 523
 524 void
 525 Timeline::setup_pixels_per_second ()
 526 {
 527         shared_ptr<const Film> film = _film.lock ();
 528         if (!film || film->length() == DCPTime ()) {
 529                 return;
 530         }
 531
 532         _pixels_per_second = static_cast<double>(width() - x_offset() * 2) / film->length().seconds ();
 533 }
 534
 535 shared_ptr<View>
 536 Timeline::event_to_view (wxMouseEvent& ev)
 537 {
 538         ViewList::iterator i = _views.begin();
 539         Position<int> const p (ev.GetX(), ev.GetY());
 540         while (i != _views.end() && !(*i)->bbox().contains (p)) {
 541                 ++i;
 542         }
 543
 544         if (i == _views.end ()) {
 545                 return shared_ptr<View> ();
 546         }
 547
 548         return *i;
 549 }
 550
 551 void
 552 Timeline::left_down (wxMouseEvent& ev)
 553 {
 554         shared_ptr<View> view = event_to_view (ev);
 555         shared_ptr<ContentView> content_view = dynamic_pointer_cast<ContentView> (view);
 556
 557         _down_view.reset ();
 558
 559         if (content_view) {
 560                 _down_view = content_view;
 561                 _down_view_position = content_view->content()->position ();
 562         }
 563
 564         for (ViewList::iterator i = _views.begin(); i != _views.end(); ++i) {
 565                 shared_ptr<ContentView> cv = dynamic_pointer_cast<ContentView> (*i);
 566                 if (!cv) {
 567                         continue;
 568                 }
 569
 570                 if (!ev.ShiftDown ()) {
 571                         cv->set_selected (view == *i);
 572                 }
 573
 574                 if (view == *i) {
 575                         _film_editor->set_selection (cv->content ());
 576                 }
 577         }
 578
 579         if (content_view && ev.ShiftDown ()) {
 580                 content_view->set_selected (!content_view->selected ());
 581         }
 582
 583         _left_down = true;
 584         _down_point = ev.GetPosition ();
 585         _first_move = false;
 586
 587         if (_down_view) {
 588                 _down_view->content()->set_change_signals_frequent (true);
 589         }
 590 }
 591
 592 void
 593 Timeline::left_up (wxMouseEvent& ev)
 594 {
 595         _left_down = false;
 596
 597         if (_down_view) {
 598                 _down_view->content()->set_change_signals_frequent (false);
 599         }
 600
 601         set_position_from_event (ev);
 602 }
 603
 604 void
 605 Timeline::mouse_moved (wxMouseEvent& ev)
 606 {
 607         if (!_left_down) {
 608                 return;
 609         }
 610
 611         set_position_from_event (ev);
 612 }
 613
 614 void
 615 Timeline::right_down (wxMouseEvent& ev)
 616 {
 617         shared_ptr<View> view = event_to_view (ev);
 618         shared_ptr<ContentView> cv = dynamic_pointer_cast<ContentView> (view);
 619         if (!cv) {
 620                 return;
 621         }
 622
 623         if (!cv->selected ()) {
 624                 clear_selection ();
 625                 cv->set_selected (true);
 626         }
 627
 628         _menu.popup (_film, selected_content (), ev.GetPosition ());
 629 }
 630
 631 void
 632 Timeline::set_position_from_event (wxMouseEvent& ev)
 633 {
 634         if (!_pixels_per_second) {
 635                 return;
 636         }
 637
 638         double const pps = _pixels_per_second.get ();
 639
 640         wxPoint const p = ev.GetPosition();
 641
 642         if (!_first_move) {
 643                 /* We haven't moved yet; in that case, we must move the mouse some reasonable distance
 644                    before the drag is considered to have started.
 645                 */
 646                 int const dist = sqrt (pow (p.x - _down_point.x, 2) + pow (p.y - _down_point.y, 2));
 647                 if (dist < 8) {
 648                         return;
 649                 }
 650                 _first_move = true;
 651         }
 652
 653         if (!_down_view) {
 654                 return;
 655         }
 656
 657         DCPTime new_position = _down_view_position + DCPTime::from_seconds ((p.x - _down_point.x) / pps);
 658
 659         if (_snap) {
 660
 661                 bool first = true;
 662                 DCPTime nearest_distance = DCPTime::max ();
 663                 DCPTime nearest_new_position = DCPTime::max ();
 664
 665                 /* Find the nearest content edge; this is inefficient */
 666                 for (ViewList::iterator i = _views.begin(); i != _views.end(); ++i) {
 667                         shared_ptr<ContentView> cv = dynamic_pointer_cast<ContentView> (*i);
 668                         if (!cv || cv == _down_view) {
 669                                 continue;
 670                         }
 671
 672                         {
 673                                 /* Snap starts to ends */
 674                                 DCPTime const d = DCPTime (cv->content()->end() - new_position).abs ();
 675                                 if (first || d < nearest_distance) {
 676                                         nearest_distance = d;
 677                                         nearest_new_position = cv->content()->end();
 678                                 }
 679                         }
 680
 681                         {
 682                                 /* Snap ends to starts */
 683                                 DCPTime const d = DCPTime (
 684                                         cv->content()->position() - (new_position + _down_view->content()->length_after_trim())
 685                                         ).abs ();
 686
 687                                 if (d < nearest_distance) {
 688                                         nearest_distance = d;
 689                                         nearest_new_position = cv->content()->position() - _down_view->content()->length_after_trim ();
 690                                 }
 691                         }
 692
 693                         first = false;
 694                 }
 695
 696                 if (!first) {
 697                         /* Snap if it's close; `close' means within a proportion of the time on the timeline */
 698                         if (nearest_distance < DCPTime::from_seconds ((width() / pps) / 32)) {
 699                                 new_position = nearest_new_position;
 700                         }
 701                 }
 702         }
 703
 704         if (new_position < DCPTime ()) {
 705                 new_position = DCPTime ();
 706         }
 707
 708         _down_view->content()->set_position (new_position);
 709
 710         shared_ptr<Film> film = _film.lock ();
 711         assert (film);
 712         film->set_sequence_video (false);
 713 }
 714
 715 void
 716 Timeline::force_redraw (dcpomatic::Rect<int> const & r)
 717 {
 718         RefreshRect (wxRect (r.x, r.y, r.width, r.height), false);
 719 }
 720
 721 shared_ptr<const Film>
 722 Timeline::film () const
 723 {
 724         return _film.lock ();
 725 }
 726
 727 void
 728 Timeline::resized ()
 729 {
 730         setup_pixels_per_second ();
 731 }
 732
 733 void
 734 Timeline::clear_selection ()
 735 {
 736         for (ViewList::iterator i = _views.begin(); i != _views.end(); ++i) {
 737                 shared_ptr<ContentView> cv = dynamic_pointer_cast<ContentView> (*i);
 738                 if (cv) {
 739                         cv->set_selected (false);
 740                 }
 741         }
 742 }
 743
 744 Timeline::ContentViewList
 745 Timeline::selected_views () const
 746 {
 747         ContentViewList sel;
 748
 749         for (ViewList::const_iterator i = _views.begin(); i != _views.end(); ++i) {
 750                 shared_ptr<ContentView> cv = dynamic_pointer_cast<ContentView> (*i);
 751                 if (cv && cv->selected()) {
 752                         sel.push_back (cv);
 753                 }
 754         }
 755
 756         return sel;
 757 }
 758
 759 ContentList
 760 Timeline::selected_content () const
 761 {
 762         ContentList sel;
 763         ContentViewList views = selected_views ();
 764
 765         for (ContentViewList::const_iterator i = views.begin(); i != views.end(); ++i) {
 766                 sel.push_back ((*i)->content ());
 767         }
 768
 769         return sel;
 770 }