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