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