pv/views/trace/view.cpp

   1 /*
   2  * This file is part of the PulseView project.
   3  *
   4  * Copyright (C) 2012 Joel Holdsworth <joel@airwebreathe.org.uk>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #ifdef ENABLE_DECODE
  21 #include <libsigrokdecode/libsigrokdecode.h>
  22 #endif
  23
  24 #include <extdef.h>
  25
  26 #include <algorithm>
  27 #include <cassert>
  28 #include <climits>
  29 #include <cmath>
  30 #include <iostream>
  31 #include <iterator>
  32 #include <unordered_set>
  33
  34 #include <boost/archive/text_iarchive.hpp>
  35 #include <boost/archive/text_oarchive.hpp>
  36 #include <boost/serialization/serialization.hpp>
  37
  38 #include <QApplication>
  39 #include <QEvent>
  40 #include <QFontMetrics>
  41 #include <QMouseEvent>
  42 #include <QScrollBar>
  43 #include <QVBoxLayout>
  44
  45 #include <libsigrokcxx/libsigrokcxx.hpp>
  46
  47 #include "analogsignal.hpp"
  48 #include "header.hpp"
  49 #include "logicsignal.hpp"
  50 #include "ruler.hpp"
  51 #include "signal.hpp"
  52 #include "tracegroup.hpp"
  53 #include "triggermarker.hpp"
  54 #include "view.hpp"
  55 #include "viewport.hpp"
  56
  57 #include "pv/data/logic.hpp"
  58 #include "pv/data/logicsegment.hpp"
  59 #include "pv/devices/device.hpp"
  60 #include "pv/globalsettings.hpp"
  61 #include "pv/session.hpp"
  62 #include "pv/util.hpp"
  63
  64 #ifdef ENABLE_DECODE
  65 #include "decodetrace.hpp"
  66 #endif
  67
  68 using pv::data::SignalData;
  69 using pv::data::Segment;
  70 using pv::util::TimeUnit;
  71 using pv::util::Timestamp;
  72
  73 using std::back_inserter;
  74 using std::copy_if;
  75 using std::count_if;
  76 using std::inserter;
  77 using std::max;
  78 using std::make_pair;
  79 using std::make_shared;
  80 using std::min;
  81 using std::pair;
  82 using std::set;
  83 using std::set_difference;
  84 using std::shared_ptr;
  85 using std::stringstream;
  86 using std::unordered_map;
  87 using std::unordered_set;
  88 using std::vector;
  89
  90 namespace pv {
  91 namespace views {
  92 namespace trace {
  93
  94 const Timestamp View::MaxScale("1e9");
  95 const Timestamp View::MinScale("1e-12");
  96
  97 const int View::MaxScrollValue = INT_MAX / 2;
  98
  99 const int View::ScaleUnits[3] = {1, 2, 5};
 100
 101
 102 CustomScrollArea::CustomScrollArea(QWidget *parent) :
 103         QAbstractScrollArea(parent)
 104 {
 105 }
 106
 107 bool CustomScrollArea::viewportEvent(QEvent *event)
 108 {
 109         switch (event->type()) {
 110         case QEvent::Paint:
 111         case QEvent::MouseButtonPress:
 112         case QEvent::MouseButtonRelease:
 113         case QEvent::MouseButtonDblClick:
 114         case QEvent::MouseMove:
 115         case QEvent::Wheel:
 116         case QEvent::TouchBegin:
 117         case QEvent::TouchUpdate:
 118         case QEvent::TouchEnd:
 119                 return false;
 120         default:
 121                 return QAbstractScrollArea::viewportEvent(event);
 122         }
 123 }
 124
 125 View::View(Session &session, bool is_main_view, QWidget *parent) :
 126         ViewBase(session, is_main_view, parent),
 127         splitter_(new QSplitter()),
 128         scale_(1e-3),
 129         offset_(0),
 130         updating_scroll_(false),
 131         settings_restored_(false),
 132         header_was_shrunk_(false),
 133         sticky_scrolling_(false), // Default setting is set in MainWindow::setup_ui()
 134         always_zoom_to_fit_(false),
 135         tick_period_(0),
 136         tick_prefix_(pv::util::SIPrefix::yocto),
 137         tick_precision_(0),
 138         time_unit_(util::TimeUnit::Time),
 139         show_cursors_(false),
 140         cursors_(new CursorPair(*this)),
 141         next_flag_text_('A'),
 142         trigger_markers_(),
 143         hover_point_(-1, -1),
 144         scroll_needs_defaults_(true),
 145         saved_v_offset_(0),
 146         scale_at_acq_start_(0),
 147         offset_at_acq_start_(0),
 148         suppress_zoom_to_fit_after_acq_(false)
 149 {
 150         QVBoxLayout *root_layout = new QVBoxLayout(this);
 151         root_layout->setContentsMargins(0, 0, 0, 0);
 152         root_layout->addWidget(splitter_);
 153
 154         viewport_ = new Viewport(*this);
 155         scrollarea_ = new CustomScrollArea(splitter_);
 156         scrollarea_->setViewport(viewport_);
 157         scrollarea_->setFrameShape(QFrame::NoFrame);
 158
 159         ruler_ = new Ruler(*this);
 160
 161         header_ = new Header(*this);
 162         header_->setMinimumWidth(10);  // So that the arrow tips show at least
 163
 164         // We put the header into a simple layout so that we can add the top margin,
 165         // allowing us to make it line up with the bottom of the ruler
 166         QWidget *header_container = new QWidget();
 167         header_container->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
 168         QVBoxLayout *header_layout = new QVBoxLayout(header_container);
 169         header_layout->setContentsMargins(0, ruler_->sizeHint().height(), 0, 0);
 170         header_layout->addWidget(header_);
 171
 172         // To let the ruler and scrollarea be on the same split pane, we need a layout
 173         QWidget *trace_container = new QWidget();
 174         trace_container->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
 175         QVBoxLayout *trace_layout = new QVBoxLayout(trace_container);
 176         trace_layout->setSpacing(0);  // We don't want space between the ruler and scrollarea
 177         trace_layout->setContentsMargins(0, 0, 0, 0);
 178         trace_layout->addWidget(ruler_);
 179         trace_layout->addWidget(scrollarea_);
 180
 181         splitter_->addWidget(header_container);
 182         splitter_->addWidget(trace_container);
 183         splitter_->setHandleWidth(1);  // Don't show a visible rubber band
 184         splitter_->setCollapsible(0, false);  // Prevent the header from collapsing
 185         splitter_->setCollapsible(1, false);  // Prevent the traces from collapsing
 186         splitter_->setStretchFactor(0, 0);  // Prevent the panes from being resized
 187         splitter_->setStretchFactor(1, 1);  // when the entire view is resized
 188         splitter_->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
 189
 190         viewport_->installEventFilter(this);
 191         ruler_->installEventFilter(this);
 192         header_->installEventFilter(this);
 193
 194         // Set up settings and event handlers
 195         GlobalSettings settings;
 196         coloured_bg_ = settings.value(GlobalSettings::Key_View_ColouredBG).toBool();
 197
 198         connect(scrollarea_->horizontalScrollBar(), SIGNAL(valueChanged(int)),
 199                 this, SLOT(h_scroll_value_changed(int)));
 200         connect(scrollarea_->verticalScrollBar(), SIGNAL(valueChanged(int)),
 201                 this, SLOT(v_scroll_value_changed()));
 202
 203         connect(header_, SIGNAL(selection_changed()),
 204                 ruler_, SLOT(clear_selection()));
 205         connect(ruler_, SIGNAL(selection_changed()),
 206                 header_, SLOT(clear_selection()));
 207
 208         connect(header_, SIGNAL(selection_changed()),
 209                 this, SIGNAL(selection_changed()));
 210         connect(ruler_, SIGNAL(selection_changed()),
 211                 this, SIGNAL(selection_changed()));
 212
 213         connect(splitter_, SIGNAL(splitterMoved(int, int)),
 214                 this, SLOT(on_splitter_moved()));
 215
 216         connect(&lazy_event_handler_, SIGNAL(timeout()),
 217                 this, SLOT(process_sticky_events()));
 218         lazy_event_handler_.setSingleShot(true);
 219
 220         // Trigger the initial event manually. The default device has signals
 221         // which were created before this object came into being
 222         signals_changed();
 223
 224         // make sure the transparent widgets are on the top
 225         ruler_->raise();
 226         header_->raise();
 227
 228         // Update the zoom state
 229         calculate_tick_spacing();
 230 }
 231
 232 Session& View::session()
 233 {
 234         return session_;
 235 }
 236
 237 const Session& View::session() const
 238 {
 239         return session_;
 240 }
 241
 242 unordered_set< shared_ptr<Signal> > View::signals() const
 243 {
 244         return signals_;
 245 }
 246
 247 void View::clear_signals()
 248 {
 249         ViewBase::clear_signalbases();
 250         signals_.clear();
 251 }
 252
 253 void View::add_signal(const shared_ptr<Signal> signal)
 254 {
 255         ViewBase::add_signalbase(signal->base());
 256         signals_.insert(signal);
 257
 258         connect(signal->base().get(), SIGNAL(name_changed(const QString&)),
 259                 this, SLOT(on_signal_name_changed()));
 260 }
 261
 262 #ifdef ENABLE_DECODE
 263 void View::clear_decode_signals()
 264 {
 265         decode_traces_.clear();
 266 }
 267
 268 void View::add_decode_signal(shared_ptr<data::DecodeSignal> signal)
 269 {
 270         shared_ptr<DecodeTrace> d(
 271                 new DecodeTrace(session_, signal, decode_traces_.size()));
 272         decode_traces_.push_back(d);
 273
 274         connect(signal.get(), SIGNAL(name_changed(const QString&)),
 275                 this, SLOT(on_signal_name_changed()));
 276 }
 277
 278 void View::remove_decode_signal(shared_ptr<data::DecodeSignal> signal)
 279 {
 280         for (auto i = decode_traces_.begin(); i != decode_traces_.end(); i++)
 281                 if ((*i)->base() == signal) {
 282                         decode_traces_.erase(i);
 283                         signals_changed();
 284                         return;
 285                 }
 286 }
 287 #endif
 288
 289 View* View::view()
 290 {
 291         return this;
 292 }
 293
 294 const View* View::view() const
 295 {
 296         return this;
 297 }
 298
 299 Viewport* View::viewport()
 300 {
 301         return viewport_;
 302 }
 303
 304 const Viewport* View::viewport() const
 305 {
 306         return viewport_;
 307 }
 308
 309 void View::save_settings(QSettings &settings) const
 310 {
 311         settings.setValue("scale", scale_);
 312         settings.setValue("v_offset",
 313                 scrollarea_->verticalScrollBar()->sliderPosition());
 314
 315         settings.setValue("splitter_state", splitter_->saveState());
 316
 317         stringstream ss;
 318         boost::archive::text_oarchive oa(ss);
 319         oa << boost::serialization::make_nvp("offset", offset_);
 320         settings.setValue("offset", QString::fromStdString(ss.str()));
 321
 322         for (shared_ptr<Signal> signal : signals_) {
 323                 settings.beginGroup(signal->base()->internal_name());
 324                 signal->save_settings(settings);
 325                 settings.endGroup();
 326         }
 327 }
 328
 329 void View::restore_settings(QSettings &settings)
 330 {
 331         // Note: It is assumed that this function is only called once,
 332         // immediately after restoring a previous session.
 333
 334         if (settings.contains("scale"))
 335                 set_scale(settings.value("scale").toDouble());
 336
 337         if (settings.contains("offset")) {
 338                 util::Timestamp offset;
 339                 stringstream ss;
 340                 ss << settings.value("offset").toString().toStdString();
 341
 342                 boost::archive::text_iarchive ia(ss);
 343                 ia >> boost::serialization::make_nvp("offset", offset);
 344
 345                 set_offset(offset);
 346         }
 347
 348         if (settings.contains("splitter_state"))
 349                 splitter_->restoreState(settings.value("splitter_state").toByteArray());
 350
 351         for (shared_ptr<Signal> signal : signals_) {
 352                 settings.beginGroup(signal->base()->internal_name());
 353                 signal->restore_settings(settings);
 354                 settings.endGroup();
 355         }
 356
 357         if (settings.contains("v_offset")) {
 358                 saved_v_offset_ = settings.value("v_offset").toInt();
 359                 set_v_offset(saved_v_offset_);
 360                 scroll_needs_defaults_ = false;
 361                 // Note: see eventFilter() for additional information
 362         }
 363
 364         settings_restored_ = true;
 365         suppress_zoom_to_fit_after_acq_ = true;
 366
 367         // Update the ruler so that it uses the new scale
 368         calculate_tick_spacing();
 369 }
 370
 371 vector< shared_ptr<TimeItem> > View::time_items() const
 372 {
 373         const vector<shared_ptr<Flag>> f(flags());
 374         vector<shared_ptr<TimeItem>> items(f.begin(), f.end());
 375         items.push_back(cursors_);
 376         items.push_back(cursors_->first());
 377         items.push_back(cursors_->second());
 378
 379         for (auto trigger_marker : trigger_markers_)
 380                 items.push_back(trigger_marker);
 381
 382         return items;
 383 }
 384
 385 double View::scale() const
 386 {
 387         return scale_;
 388 }
 389
 390 void View::set_scale(double scale)
 391 {
 392         if (scale_ != scale) {
 393                 scale_ = scale;
 394                 scale_changed();
 395         }
 396 }
 397
 398 const Timestamp& View::offset() const
 399 {
 400         return offset_;
 401 }
 402
 403 void View::set_offset(const pv::util::Timestamp& offset)
 404 {
 405         if (offset_ != offset) {
 406                 offset_ = offset;
 407                 offset_changed();
 408         }
 409 }
 410
 411 int View::owner_visual_v_offset() const
 412 {
 413         return -scrollarea_->verticalScrollBar()->sliderPosition();
 414 }
 415
 416 void View::set_v_offset(int offset)
 417 {
 418         scrollarea_->verticalScrollBar()->setSliderPosition(offset);
 419         header_->update();
 420         viewport_->update();
 421 }
 422
 423 unsigned int View::depth() const
 424 {
 425         return 0;
 426 }
 427
 428 pv::util::SIPrefix View::tick_prefix() const
 429 {
 430         return tick_prefix_;
 431 }
 432
 433 void View::set_tick_prefix(pv::util::SIPrefix tick_prefix)
 434 {
 435         if (tick_prefix_ != tick_prefix) {
 436                 tick_prefix_ = tick_prefix;
 437                 tick_prefix_changed();
 438         }
 439 }
 440
 441 unsigned int View::tick_precision() const
 442 {
 443         return tick_precision_;
 444 }
 445
 446 void View::set_tick_precision(unsigned tick_precision)
 447 {
 448         if (tick_precision_ != tick_precision) {
 449                 tick_precision_ = tick_precision;
 450                 tick_precision_changed();
 451         }
 452 }
 453
 454 const pv::util::Timestamp& View::tick_period() const
 455 {
 456         return tick_period_;
 457 }
 458
 459 void View::set_tick_period(const pv::util::Timestamp& tick_period)
 460 {
 461         if (tick_period_ != tick_period) {
 462                 tick_period_ = tick_period;
 463                 tick_period_changed();
 464         }
 465 }
 466
 467 TimeUnit View::time_unit() const
 468 {
 469         return time_unit_;
 470 }
 471
 472 void View::set_time_unit(pv::util::TimeUnit time_unit)
 473 {
 474         if (time_unit_ != time_unit) {
 475                 time_unit_ = time_unit;
 476                 time_unit_changed();
 477         }
 478 }
 479
 480 void View::zoom(double steps)
 481 {
 482         zoom(steps, viewport_->width() / 2);
 483 }
 484
 485 void View::zoom(double steps, int offset)
 486 {
 487         set_zoom(scale_ * pow(3.0 / 2.0, -steps), offset);
 488 }
 489
 490 void View::zoom_fit(bool gui_state)
 491 {
 492         // Act as one-shot when stopped, toggle along with the GUI otherwise
 493         if (session_.get_capture_state() == Session::Stopped) {
 494                 always_zoom_to_fit_ = false;
 495                 always_zoom_to_fit_changed(false);
 496         } else {
 497                 always_zoom_to_fit_ = gui_state;
 498                 always_zoom_to_fit_changed(gui_state);
 499         }
 500
 501         const pair<Timestamp, Timestamp> extents = get_time_extents();
 502         const Timestamp delta = extents.second - extents.first;
 503         if (delta < Timestamp("1e-12"))
 504                 return;
 505
 506         assert(viewport_);
 507         const int w = viewport_->width();
 508         if (w <= 0)
 509                 return;
 510
 511         const Timestamp scale = max(min(delta / w, MaxScale), MinScale);
 512         set_scale_offset(scale.convert_to<double>(), extents.first);
 513 }
 514
 515 void View::zoom_one_to_one()
 516 {
 517         using pv::data::SignalData;
 518
 519         // Make a set of all the visible data objects
 520         set< shared_ptr<SignalData> > visible_data = get_visible_data();
 521         if (visible_data.empty())
 522                 return;
 523
 524         assert(viewport_);
 525         const int w = viewport_->width();
 526         if (w <= 0)
 527                 return;
 528
 529         set_zoom(1.0 / session_.get_samplerate(), w / 2);
 530 }
 531
 532 void View::set_scale_offset(double scale, const Timestamp& offset)
 533 {
 534         // Disable sticky scrolling / always zoom to fit when acquisition runs
 535         // and user drags the viewport
 536         if ((scale_ == scale) && (offset_ != offset) &&
 537                         (session_.get_capture_state() == Session::Running)) {
 538
 539                 if (sticky_scrolling_) {
 540                         sticky_scrolling_ = false;
 541                         sticky_scrolling_changed(false);
 542                 }
 543
 544                 if (always_zoom_to_fit_) {
 545                         always_zoom_to_fit_ = false;
 546                         always_zoom_to_fit_changed(false);
 547                 }
 548         }
 549
 550         set_scale(scale);
 551         set_offset(offset);
 552
 553         calculate_tick_spacing();
 554
 555         update_scroll();
 556         ruler_->update();
 557         viewport_->update();
 558 }
 559
 560 set< shared_ptr<SignalData> > View::get_visible_data() const
 561 {
 562         // Make a set of all the visible data objects
 563         set< shared_ptr<SignalData> > visible_data;
 564         for (const shared_ptr<Signal> sig : signals_)
 565                 if (sig->enabled())
 566                         visible_data.insert(sig->data());
 567
 568         return visible_data;
 569 }
 570
 571 pair<Timestamp, Timestamp> View::get_time_extents() const
 572 {
 573         boost::optional<Timestamp> left_time, right_time;
 574         const set< shared_ptr<SignalData> > visible_data = get_visible_data();
 575         for (const shared_ptr<SignalData> d : visible_data) {
 576                 const vector< shared_ptr<Segment> > segments = d->segments();
 577                 for (const shared_ptr<Segment> &s : segments) {
 578                         double samplerate = s->samplerate();
 579                         samplerate = (samplerate <= 0.0) ? 1.0 : samplerate;
 580
 581                         const Timestamp start_time = s->start_time();
 582                         left_time = left_time ?
 583                                 min(*left_time, start_time) :
 584                                                 start_time;
 585                         right_time = right_time ?
 586                                 max(*right_time, start_time + d->max_sample_count() / samplerate) :
 587                                                  start_time + d->max_sample_count() / samplerate;
 588                 }
 589         }
 590
 591         if (!left_time || !right_time)
 592                 return make_pair(0, 0);
 593
 594         assert(*left_time < *right_time);
 595         return make_pair(*left_time, *right_time);
 596 }
 597
 598 void View::enable_show_sampling_points(bool state)
 599 {
 600         (void)state;
 601
 602         viewport_->update();
 603 }
 604
 605 void View::enable_show_analog_minor_grid(bool state)
 606 {
 607         (void)state;
 608
 609         viewport_->update();
 610 }
 611
 612 void View::enable_coloured_bg(bool state)
 613 {
 614         coloured_bg_ = state;
 615         viewport_->update();
 616 }
 617
 618 bool View::coloured_bg() const
 619 {
 620         return coloured_bg_;
 621 }
 622
 623 bool View::cursors_shown() const
 624 {
 625         return show_cursors_;
 626 }
 627
 628 void View::show_cursors(bool show)
 629 {
 630         show_cursors_ = show;
 631         ruler_->update();
 632         viewport_->update();
 633 }
 634
 635 void View::centre_cursors()
 636 {
 637         const double time_width = scale_ * viewport_->width();
 638         cursors_->first()->set_time(offset_ + time_width * 0.4);
 639         cursors_->second()->set_time(offset_ + time_width * 0.6);
 640         ruler_->update();
 641         viewport_->update();
 642 }
 643
 644 shared_ptr<CursorPair> View::cursors() const
 645 {
 646         return cursors_;
 647 }
 648
 649 void View::add_flag(const Timestamp& time)
 650 {
 651         flags_.push_back(make_shared<Flag>(*this, time,
 652                 QString("%1").arg(next_flag_text_)));
 653
 654         next_flag_text_ = (next_flag_text_ >= 'Z') ? 'A' :
 655                 (next_flag_text_ + 1);
 656
 657         time_item_appearance_changed(true, true);
 658 }
 659
 660 void View::remove_flag(shared_ptr<Flag> flag)
 661 {
 662         flags_.remove(flag);
 663         time_item_appearance_changed(true, true);
 664 }
 665
 666 vector< shared_ptr<Flag> > View::flags() const
 667 {
 668         vector< shared_ptr<Flag> > flags(flags_.begin(), flags_.end());
 669         stable_sort(flags.begin(), flags.end(),
 670                 [](const shared_ptr<Flag> &a, const shared_ptr<Flag> &b) {
 671                         return a->time() < b->time();
 672                 });
 673
 674         return flags;
 675 }
 676
 677 const QPoint& View::hover_point() const
 678 {
 679         return hover_point_;
 680 }
 681
 682 void View::restack_all_trace_tree_items()
 683 {
 684         // Make a list of owners that is sorted from deepest first
 685         const vector<shared_ptr<TraceTreeItem>> items(
 686                 list_by_type<TraceTreeItem>());
 687         set< TraceTreeItemOwner* > owners;
 688         for (const auto &r : items)
 689                 owners.insert(r->owner());
 690         vector< TraceTreeItemOwner* > sorted_owners(owners.begin(), owners.end());
 691         sort(sorted_owners.begin(), sorted_owners.end(),
 692                 [](const TraceTreeItemOwner* a, const TraceTreeItemOwner *b) {
 693                         return a->depth() > b->depth(); });
 694
 695         // Restack the items recursively
 696         for (auto &o : sorted_owners)
 697                 o->restack_items();
 698
 699         // Animate the items to their destination
 700         for (const auto &i : items)
 701                 i->animate_to_layout_v_offset();
 702 }
 703
 704 void View::trigger_event(util::Timestamp location)
 705 {
 706         trigger_markers_.push_back(make_shared<TriggerMarker>(*this, location));
 707 }
 708
 709 void View::get_scroll_layout(double &length, Timestamp &offset) const
 710 {
 711         const pair<Timestamp, Timestamp> extents = get_time_extents();
 712         length = ((extents.second - extents.first) / scale_).convert_to<double>();
 713         offset = offset_ / scale_;
 714 }
 715
 716 void View::set_zoom(double scale, int offset)
 717 {
 718         // Reset the "always zoom to fit" feature as the user changed the zoom
 719         always_zoom_to_fit_ = false;
 720         always_zoom_to_fit_changed(false);
 721
 722         const Timestamp cursor_offset = offset_ + scale_ * offset;
 723         const Timestamp new_scale = max(min(Timestamp(scale), MaxScale), MinScale);
 724         const Timestamp new_offset = cursor_offset - new_scale * offset;
 725         set_scale_offset(new_scale.convert_to<double>(), new_offset);
 726 }
 727
 728 void View::calculate_tick_spacing()
 729 {
 730         const double SpacingIncrement = 10.0f;
 731         const double MinValueSpacing = 40.0f;
 732
 733         // Figure out the highest numeric value visible on a label
 734         const QSize areaSize = viewport_->size();
 735         const Timestamp max_time = max(fabs(offset_),
 736                 fabs(offset_ + scale_ * areaSize.width()));
 737
 738         double min_width = SpacingIncrement;
 739         double label_width, tick_period_width;
 740
 741         QFontMetrics m(QApplication::font());
 742
 743         // Copies of the member variables with the same name, used in the calculation
 744         // and written back afterwards, so that we don't emit signals all the time
 745         // during the calculation.
 746         pv::util::Timestamp tick_period = tick_period_;
 747         pv::util::SIPrefix tick_prefix = tick_prefix_;
 748         unsigned tick_precision = tick_precision_;
 749
 750         do {
 751                 const double min_period = scale_ * min_width;
 752
 753                 const int order = (int)floorf(log10f(min_period));
 754                 const pv::util::Timestamp order_decimal =
 755                         pow(pv::util::Timestamp(10), order);
 756
 757                 // Allow for a margin of error so that a scale unit of 1 can be used.
 758                 // Otherwise, for a SU of 1 the tick period will almost always be below
 759                 // the min_period by a small amount - and thus skipped in favor of 2.
 760                 // Note: margin assumes that SU[0] and SU[1] contain the smallest values
 761                 double tp_margin = (ScaleUnits[0] + ScaleUnits[1]) / 2.0;
 762                 double tp_with_margin;
 763                 unsigned int unit = 0;
 764
 765                 do {
 766                         tp_with_margin = order_decimal.convert_to<double>() *
 767                                 (ScaleUnits[unit++] + tp_margin);
 768                 } while (tp_with_margin < min_period && unit < countof(ScaleUnits));
 769
 770                 tick_period = order_decimal * ScaleUnits[unit - 1];
 771                 tick_prefix = static_cast<pv::util::SIPrefix>(
 772                         (order - pv::util::exponent(pv::util::SIPrefix::yocto)) / 3);
 773
 774                 // Precision is the number of fractional digits required, not
 775                 // taking the prefix into account (and it must never be negative)
 776                 tick_precision = max(ceil(log10(1 / tick_period)).convert_to<int>(), 0);
 777
 778                 tick_period_width = (tick_period / scale_).convert_to<double>();
 779
 780                 const QString label_text = Ruler::format_time_with_distance(
 781                         tick_period, max_time, tick_prefix, time_unit_, tick_precision);
 782
 783                 label_width = m.boundingRect(0, 0, INT_MAX, INT_MAX,
 784                         Qt::AlignLeft | Qt::AlignTop, label_text).width() +
 785                                 MinValueSpacing;
 786
 787                 min_width += SpacingIncrement;
 788         } while (tick_period_width < label_width);
 789
 790         set_tick_period(tick_period);
 791         set_tick_prefix(tick_prefix);
 792         set_tick_precision(tick_precision);
 793 }
 794
 795 void View::adjust_top_margin()
 796 {
 797         assert(viewport_);
 798
 799         const QSize areaSize = viewport_->size();
 800
 801         const pair<int, int> extents = v_extents();
 802         const int top_margin = owner_visual_v_offset() + extents.first;
 803         const int trace_bottom = owner_visual_v_offset() + extents.first + extents.second;
 804
 805         // Do we have empty space at the top while the last trace goes out of screen?
 806         if ((top_margin > 0) && (trace_bottom > areaSize.height())) {
 807                 const int trace_height = extents.second - extents.first;
 808
 809                 // Center everything vertically if there is enough space
 810                 if (areaSize.height() >= trace_height)
 811                         set_v_offset(extents.first -
 812                                 ((areaSize.height() - trace_height) / 2));
 813                 else
 814                         // Remove the top margin to make as many traces fit on screen as possible
 815                         set_v_offset(extents.first);
 816         }
 817 }
 818
 819 void View::update_scroll()
 820 {
 821         assert(viewport_);
 822         QScrollBar *hscrollbar = scrollarea_->horizontalScrollBar();
 823         QScrollBar *vscrollbar = scrollarea_->verticalScrollBar();
 824
 825         const QSize areaSize = viewport_->size();
 826
 827         // Set the horizontal scroll bar
 828         double length = 0;
 829         Timestamp offset;
 830         get_scroll_layout(length, offset);
 831         length = max(length - areaSize.width(), 0.0);
 832
 833         int major_tick_distance = (tick_period_ / scale_).convert_to<int>();
 834
 835         hscrollbar->setPageStep(areaSize.width() / 2);
 836         hscrollbar->setSingleStep(major_tick_distance);
 837
 838         updating_scroll_ = true;
 839
 840         if (length < MaxScrollValue) {
 841                 hscrollbar->setRange(0, length);
 842                 hscrollbar->setSliderPosition(offset.convert_to<double>());
 843         } else {
 844                 hscrollbar->setRange(0, MaxScrollValue);
 845                 hscrollbar->setSliderPosition(
 846                         (offset_ * MaxScrollValue / (scale_ * length)).convert_to<double>());
 847         }
 848
 849         updating_scroll_ = false;
 850
 851         // Set the vertical scrollbar
 852         vscrollbar->setPageStep(areaSize.height());
 853         vscrollbar->setSingleStep(areaSize.height() / 8);
 854
 855         const pair<int, int> extents = v_extents();
 856
 857         // Don't change the scrollbar range if there are no traces
 858         if (extents.first != extents.second)
 859                 vscrollbar->setRange(extents.first - areaSize.height(),
 860                         extents.second);
 861
 862         if (scroll_needs_defaults_)
 863                 set_scroll_default();
 864 }
 865
 866 void View::reset_scroll()
 867 {
 868         scrollarea_->verticalScrollBar()->setRange(0, 0);
 869 }
 870
 871 void View::set_scroll_default()
 872 {
 873         assert(viewport_);
 874
 875         const QSize areaSize = viewport_->size();
 876
 877         const pair<int, int> extents = v_extents();
 878         const int trace_height = extents.second - extents.first;
 879
 880         // Do all traces fit in the view?
 881         if (areaSize.height() >= trace_height)
 882                 // Center all traces vertically
 883                 set_v_offset(extents.first -
 884                         ((areaSize.height() - trace_height) / 2));
 885         else
 886                 // Put the first trace at the top, letting the bottom ones overflow
 887                 set_v_offset(extents.first);
 888 }
 889
 890 void View::determine_if_header_was_shrunk()
 891 {
 892         const int header_pane_width = splitter_->sizes().front();
 893         const int header_width = header_->extended_size_hint().width();
 894
 895         // Allow for a slight margin of error so that we also accept
 896         // slight differences when e.g. a label name change increased
 897         // the overall width
 898         header_was_shrunk_ = (header_pane_width < (header_width - 10));
 899 }
 900
 901 void View::resize_header_to_fit()
 902 {
 903         // Setting the maximum width of the header widget doesn't work as
 904         // expected because the splitter would allow the user to make the
 905         // pane wider than that, creating empty space as a result.
 906         // To make this work, we stricly enforce the maximum width by
 907         // expanding the header unless the user shrunk it on purpose.
 908         // As we're then setting the width of the header pane, we set the
 909         // splitter to the maximum allowed position.
 910
 911         int splitter_area_width = 0;
 912         for (int w : splitter_->sizes())
 913                 splitter_area_width += w;
 914
 915         // Make sure the header has enough horizontal space to show all labels fully
 916         QList<int> pane_sizes;
 917         pane_sizes.push_back(header_->extended_size_hint().width());
 918         pane_sizes.push_back(splitter_area_width - header_->extended_size_hint().width());
 919         splitter_->setSizes(pane_sizes);
 920 }
 921
 922 void View::update_layout()
 923 {
 924         update_scroll();
 925 }
 926
 927 TraceTreeItemOwner* View::find_prevalent_trace_group(
 928         const shared_ptr<sigrok::ChannelGroup> &group,
 929         const unordered_map<shared_ptr<data::SignalBase>, shared_ptr<Signal> >
 930                 &signal_map)
 931 {
 932         assert(group);
 933
 934         unordered_set<TraceTreeItemOwner*> owners;
 935         vector<TraceTreeItemOwner*> owner_list;
 936
 937         // Make a set and a list of all the owners
 938         for (const auto &channel : group->channels()) {
 939                 for (auto entry : signal_map) {
 940                         if (entry.first->channel() == channel) {
 941                                 TraceTreeItemOwner *const o = (entry.second)->owner();
 942                                 owner_list.push_back(o);
 943                                 owners.insert(o);
 944                         }
 945                 }
 946         }
 947
 948         // Iterate through the list of owners, and find the most prevalent
 949         size_t max_prevalence = 0;
 950         TraceTreeItemOwner *prevalent_owner = nullptr;
 951         for (TraceTreeItemOwner *owner : owners) {
 952                 const size_t prevalence = count_if(
 953                         owner_list.begin(), owner_list.end(),
 954                         [&](TraceTreeItemOwner *o) { return o == owner; });
 955                 if (prevalence > max_prevalence) {
 956                         max_prevalence = prevalence;
 957                         prevalent_owner = owner;
 958                 }
 959         }
 960
 961         return prevalent_owner;
 962 }
 963
 964 vector< shared_ptr<Trace> > View::extract_new_traces_for_channels(
 965         const vector< shared_ptr<sigrok::Channel> > &channels,
 966         const unordered_map<shared_ptr<data::SignalBase>, shared_ptr<Signal> >
 967                 &signal_map,
 968         set< shared_ptr<Trace> > &add_list)
 969 {
 970         vector< shared_ptr<Trace> > filtered_traces;
 971
 972         for (const auto &channel : channels) {
 973                 for (auto entry : signal_map) {
 974                         if (entry.first->channel() == channel) {
 975                                 shared_ptr<Trace> trace = entry.second;
 976                                 const auto list_iter = add_list.find(trace);
 977                                 if (list_iter == add_list.end())
 978                                         continue;
 979
 980                                 filtered_traces.push_back(trace);
 981                                 add_list.erase(list_iter);
 982                         }
 983                 }
 984         }
 985
 986         return filtered_traces;
 987 }
 988
 989 void View::determine_time_unit()
 990 {
 991         // Check whether we know the sample rate and hence can use time as the unit
 992         if (time_unit_ == util::TimeUnit::Samples) {
 993                 // Check all signals but...
 994                 for (const shared_ptr<Signal> signal : signals_) {
 995                         const shared_ptr<SignalData> data = signal->data();
 996
 997                         // ...only check first segment of each
 998                         const vector< shared_ptr<Segment> > segments = data->segments();
 999                         if (!segments.empty())
1000                                 if (segments[0]->samplerate()) {
1001                                         set_time_unit(util::TimeUnit::Time);
1002                                         break;
1003                                 }
1004                 }
1005         }
1006 }
1007
1008 bool View::eventFilter(QObject *object, QEvent *event)
1009 {
1010         const QEvent::Type type = event->type();
1011         if (type == QEvent::MouseMove) {
1012
1013                 const QMouseEvent *const mouse_event = (QMouseEvent*)event;
1014                 if (object == viewport_)
1015                         hover_point_ = mouse_event->pos();
1016                 else if (object == ruler_)
1017                         hover_point_ = QPoint(mouse_event->x(), 0);
1018                 else if (object == header_)
1019                         hover_point_ = QPoint(0, mouse_event->y());
1020                 else
1021                         hover_point_ = QPoint(-1, -1);
1022
1023                 update_hover_point();
1024
1025         } else if (type == QEvent::Leave) {
1026                 hover_point_ = QPoint(-1, -1);
1027                 update_hover_point();
1028         } else if (type == QEvent::Show) {
1029
1030                 // This is somewhat of a hack, unfortunately. We cannot use
1031                 // set_v_offset() from within restore_settings() as the view
1032                 // at that point is neither visible nor properly sized.
1033                 // This is the least intrusive workaround I could come up
1034                 // with: set the vertical offset (or scroll defaults) when
1035                 // the view is shown, which happens after all widgets were
1036                 // resized to their final sizes.
1037                 update_layout();
1038
1039                 if (settings_restored_)
1040                         determine_if_header_was_shrunk();
1041                 else
1042                         resize_header_to_fit();
1043
1044                 if (scroll_needs_defaults_) {
1045                         set_scroll_default();
1046                         scroll_needs_defaults_ = false;
1047                 }
1048
1049                 if (saved_v_offset_) {
1050                         set_v_offset(saved_v_offset_);
1051                         saved_v_offset_ = 0;
1052                 }
1053         }
1054
1055         return QObject::eventFilter(object, event);
1056 }
1057
1058 void View::resizeEvent(QResizeEvent* event)
1059 {
1060         // Only adjust the top margin if we shrunk vertically
1061         if (event->size().height() < event->oldSize().height())
1062                 adjust_top_margin();
1063
1064         update_layout();
1065 }
1066
1067 void View::update_hover_point()
1068 {
1069         const vector<shared_ptr<TraceTreeItem>> trace_tree_items(
1070                 list_by_type<TraceTreeItem>());
1071         for (shared_ptr<TraceTreeItem> r : trace_tree_items)
1072                 r->hover_point_changed(hover_point_);
1073
1074         hover_point_changed(hover_point_);
1075 }
1076
1077 void View::row_item_appearance_changed(bool label, bool content)
1078 {
1079         if (label)
1080                 header_->update();
1081         if (content)
1082                 viewport_->update();
1083 }
1084
1085 void View::time_item_appearance_changed(bool label, bool content)
1086 {
1087         if (label) {
1088                 ruler_->update();
1089
1090                 // Make sure the header pane width is updated, too
1091                 update_layout();
1092         }
1093
1094         if (content)
1095                 viewport_->update();
1096 }
1097
1098 void View::extents_changed(bool horz, bool vert)
1099 {
1100         sticky_events_ |=
1101                 (horz ? TraceTreeItemHExtentsChanged : 0) |
1102                 (vert ? TraceTreeItemVExtentsChanged : 0);
1103
1104         lazy_event_handler_.start();
1105 }
1106
1107 void View::on_signal_name_changed()
1108 {
1109         if (!header_was_shrunk_)
1110                 resize_header_to_fit();
1111 }
1112
1113 void View::on_splitter_moved()
1114 {
1115         // The header can only shrink when the splitter is moved manually
1116         determine_if_header_was_shrunk();
1117
1118         if (!header_was_shrunk_)
1119                 resize_header_to_fit();
1120 }
1121
1122 void View::h_scroll_value_changed(int value)
1123 {
1124         if (updating_scroll_)
1125                 return;
1126
1127         // Disable sticky scrolling when user moves the horizontal scroll bar
1128         // during a running acquisition
1129         if (sticky_scrolling_ && (session_.get_capture_state() == Session::Running)) {
1130                 sticky_scrolling_ = false;
1131                 sticky_scrolling_changed(false);
1132         }
1133
1134         const int range = scrollarea_->horizontalScrollBar()->maximum();
1135         if (range < MaxScrollValue)
1136                 set_offset(scale_ * value);
1137         else {
1138                 double length = 0;
1139                 Timestamp offset;
1140                 get_scroll_layout(length, offset);
1141                 set_offset(scale_ * length * value / MaxScrollValue);
1142         }
1143
1144         ruler_->update();
1145         viewport_->update();
1146 }
1147
1148 void View::v_scroll_value_changed()
1149 {
1150         header_->update();
1151         viewport_->update();
1152 }
1153
1154 void View::signals_changed()
1155 {
1156         using sigrok::Channel;
1157
1158         vector< shared_ptr<Channel> > channels;
1159         shared_ptr<sigrok::Device> sr_dev;
1160         bool signals_added_or_removed = false;
1161
1162         // Do we need to set the vertical scrollbar to its default position later?
1163         // We do if there are no traces, i.e. the scroll bar has no range set
1164         bool reset_scrollbar =
1165                 (scrollarea_->verticalScrollBar()->minimum() ==
1166                         scrollarea_->verticalScrollBar()->maximum());
1167
1168         if (!session_.device()) {
1169                 reset_scroll();
1170                 signals_.clear();
1171         } else {
1172                 sr_dev = session_.device()->device();
1173                 assert(sr_dev);
1174                 channels = sr_dev->channels();
1175         }
1176
1177         vector< shared_ptr<TraceTreeItem> > new_top_level_items;
1178
1179         // Make a list of traces that are being added, and a list of traces
1180         // that are being removed
1181         const vector<shared_ptr<Trace>> prev_trace_list = list_by_type<Trace>();
1182         const set<shared_ptr<Trace>> prev_traces(
1183                 prev_trace_list.begin(), prev_trace_list.end());
1184
1185         set< shared_ptr<Trace> > traces(signals_.begin(), signals_.end());
1186
1187 #ifdef ENABLE_DECODE
1188         traces.insert(decode_traces_.begin(), decode_traces_.end());
1189 #endif
1190
1191         set< shared_ptr<Trace> > add_traces;
1192         set_difference(traces.begin(), traces.end(),
1193                 prev_traces.begin(), prev_traces.end(),
1194                 inserter(add_traces, add_traces.begin()));
1195
1196         set< shared_ptr<Trace> > remove_traces;
1197         set_difference(prev_traces.begin(), prev_traces.end(),
1198                 traces.begin(), traces.end(),
1199                 inserter(remove_traces, remove_traces.begin()));
1200
1201         // Make a look-up table of sigrok Channels to pulseview Signals
1202         unordered_map<shared_ptr<data::SignalBase>, shared_ptr<Signal> >
1203                 signal_map;
1204         for (const shared_ptr<Signal> &sig : signals_)
1205                 signal_map[sig->base()] = sig;
1206
1207         // Populate channel groups
1208         if (sr_dev)
1209                 for (auto entry : sr_dev->channel_groups()) {
1210                         const shared_ptr<sigrok::ChannelGroup> &group = entry.second;
1211
1212                         if (group->channels().size() <= 1)
1213                                 continue;
1214
1215                         // Find best trace group to add to
1216                         TraceTreeItemOwner *owner = find_prevalent_trace_group(
1217                                 group, signal_map);
1218
1219                         // If there is no trace group, create one
1220                         shared_ptr<TraceGroup> new_trace_group;
1221                         if (!owner) {
1222                                 new_trace_group.reset(new TraceGroup());
1223                                 owner = new_trace_group.get();
1224                         }
1225
1226                         // Extract traces for the trace group, removing them from
1227                         // the add list
1228                         const vector< shared_ptr<Trace> > new_traces_in_group =
1229                                 extract_new_traces_for_channels(group->channels(),
1230                                         signal_map, add_traces);
1231
1232                         // Add the traces to the group
1233                         const pair<int, int> prev_v_extents = owner->v_extents();
1234                         int offset = prev_v_extents.second - prev_v_extents.first;
1235                         for (shared_ptr<Trace> trace : new_traces_in_group) {
1236                                 assert(trace);
1237                                 owner->add_child_item(trace);
1238
1239                                 const pair<int, int> extents = trace->v_extents();
1240                                 if (trace->enabled())
1241                                         offset += -extents.first;
1242                                 trace->force_to_v_offset(offset);
1243                                 if (trace->enabled())
1244                                         offset += extents.second;
1245                         }
1246
1247                         if (new_trace_group) {
1248                                 // Assign proper vertical offsets to each channel in the group
1249                                 new_trace_group->restack_items();
1250
1251                                 // If this is a new group, enqueue it in the new top level
1252                                 // items list
1253                                 if (!new_traces_in_group.empty())
1254                                         new_top_level_items.push_back(new_trace_group);
1255                         }
1256                 }
1257
1258         // Enqueue the remaining logic channels in a group
1259         vector< shared_ptr<Channel> > logic_channels;
1260         copy_if(channels.begin(), channels.end(), back_inserter(logic_channels),
1261                 [](const shared_ptr<Channel>& c) {
1262                         return c->type() == sigrok::ChannelType::LOGIC; });
1263
1264         const vector< shared_ptr<Trace> > non_grouped_logic_signals =
1265                 extract_new_traces_for_channels(logic_channels, signal_map, add_traces);
1266
1267         if (non_grouped_logic_signals.size() > 0) {
1268                 const shared_ptr<TraceGroup> non_grouped_trace_group(
1269                         make_shared<TraceGroup>());
1270                 for (shared_ptr<Trace> trace : non_grouped_logic_signals)
1271                         non_grouped_trace_group->add_child_item(trace);
1272
1273                 non_grouped_trace_group->restack_items();
1274                 new_top_level_items.push_back(non_grouped_trace_group);
1275         }
1276
1277         // Enqueue the remaining channels as free ungrouped traces
1278         const vector< shared_ptr<Trace> > new_top_level_signals =
1279                 extract_new_traces_for_channels(channels, signal_map, add_traces);
1280         new_top_level_items.insert(new_top_level_items.end(),
1281                 new_top_level_signals.begin(), new_top_level_signals.end());
1282
1283         // Enqueue any remaining traces i.e. decode traces
1284         new_top_level_items.insert(new_top_level_items.end(),
1285                 add_traces.begin(), add_traces.end());
1286
1287         // Remove any removed traces
1288         for (shared_ptr<Trace> trace : remove_traces) {
1289                 TraceTreeItemOwner *const owner = trace->owner();
1290                 assert(owner);
1291                 owner->remove_child_item(trace);
1292                 signals_added_or_removed = true;
1293         }
1294
1295         // Remove any empty trace groups
1296         for (shared_ptr<TraceGroup> group : list_by_type<TraceGroup>())
1297                 if (group->child_items().size() == 0) {
1298                         remove_child_item(group);
1299                         group.reset();
1300                 }
1301
1302         // Add and position the pending top levels items
1303         int offset = v_extents().second;
1304         for (auto item : new_top_level_items) {
1305                 add_child_item(item);
1306
1307                 // Position the item after the last item or at the top if there is none
1308                 const pair<int, int> extents = item->v_extents();
1309
1310                 if (item->enabled())
1311                         offset += -extents.first;
1312
1313                 item->force_to_v_offset(offset);
1314
1315                 if (item->enabled())
1316                         offset += extents.second;
1317                 signals_added_or_removed = true;
1318         }
1319
1320
1321         if (signals_added_or_removed && !header_was_shrunk_)
1322                 resize_header_to_fit();
1323
1324         update_layout();
1325
1326         header_->update();
1327         viewport_->update();
1328
1329         if (reset_scrollbar)
1330                 set_scroll_default();
1331 }
1332
1333 void View::capture_state_updated(int state)
1334 {
1335         GlobalSettings settings;
1336
1337         if (state == Session::Running) {
1338                 set_time_unit(util::TimeUnit::Samples);
1339
1340                 trigger_markers_.clear();
1341
1342                 scale_at_acq_start_ = scale_;
1343                 offset_at_acq_start_ = offset_;
1344
1345                 // Activate "always zoom to fit" if the setting is enabled and we're
1346                 // the main view of this session (other trace views may be used for
1347                 // zooming and we don't want to mess them up)
1348                 bool state = settings.value(GlobalSettings::Key_View_ZoomToFitDuringAcq).toBool();
1349                 if (is_main_view_ && state) {
1350                         always_zoom_to_fit_ = true;
1351                         always_zoom_to_fit_changed(always_zoom_to_fit_);
1352                 }
1353
1354                 // Enable sticky scrolling if the setting is enabled
1355                 sticky_scrolling_ = settings.value(GlobalSettings::Key_View_StickyScrolling).toBool();
1356         }
1357
1358         if (state == Session::Stopped) {
1359                 // After acquisition has stopped we need to re-calculate the ticks once
1360                 // as it's otherwise done when the user pans or zooms, which is too late
1361                 calculate_tick_spacing();
1362
1363                 // Reset "always zoom to fit", the acquisition has stopped
1364                 if (always_zoom_to_fit_) {
1365                         // Perform a final zoom-to-fit before disabling
1366                         zoom_fit(always_zoom_to_fit_);
1367                         always_zoom_to_fit_ = false;
1368                         always_zoom_to_fit_changed(always_zoom_to_fit_);
1369                 }
1370
1371                 bool zoom_to_fit_after_acq =
1372                         settings.value(GlobalSettings::Key_View_ZoomToFitAfterAcq).toBool();
1373
1374                 // Only perform zoom-to-fit if the user hasn't altered the viewport and
1375                 // we didn't restore settings in the meanwhile
1376                 if (zoom_to_fit_after_acq &&
1377                         !suppress_zoom_to_fit_after_acq_ &&
1378                         (scale_ == scale_at_acq_start_) &&
1379                         (offset_ == offset_at_acq_start_))
1380                         zoom_fit(false);  // We're stopped, so the GUI state doesn't matter
1381
1382                 suppress_zoom_to_fit_after_acq_ = false;
1383         }
1384 }
1385
1386 void View::on_segment_changed(int segment)
1387 {
1388         current_segment_ = segment - 1;
1389
1390         for (shared_ptr<Signal> signal : signals_)
1391                 signal->set_current_segment(current_segment_);
1392
1393         viewport_->update();
1394 }
1395
1396 void View::perform_delayed_view_update()
1397 {
1398         if (always_zoom_to_fit_) {
1399                 zoom_fit(true);
1400         } else if (sticky_scrolling_) {
1401                 // Make right side of the view sticky
1402                 double length = 0;
1403                 Timestamp offset;
1404                 get_scroll_layout(length, offset);
1405
1406                 const QSize areaSize = viewport_->size();
1407                 length = max(length - areaSize.width(), 0.0);
1408
1409                 set_offset(scale_ * length);
1410         }
1411
1412         determine_time_unit();
1413         update_scroll();
1414         ruler_->update();
1415         viewport_->update();
1416 }
1417
1418 void View::process_sticky_events()
1419 {
1420         if (sticky_events_ & TraceTreeItemHExtentsChanged)
1421                 update_layout();
1422         if (sticky_events_ & TraceTreeItemVExtentsChanged) {
1423                 restack_all_trace_tree_items();
1424                 update_scroll();
1425         }
1426
1427         // Clear the sticky events
1428         sticky_events_ = 0;
1429 }
1430
1431 } // namespace trace
1432 } // namespace views
1433 } // namespace pv