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