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, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  19  */
  20
  21 #ifdef ENABLE_DECODE
  22 #include <libsigrokdecode/libsigrokdecode.h>
  23 #endif
  24
  25 #include <extdef.h>
  26
  27 #include <algorithm>
  28 #include <cassert>
  29 #include <climits>
  30 #include <cmath>
  31 #include <iterator>
  32 #include <mutex>
  33 #include <unordered_set>
  34
  35 #include <QApplication>
  36 #include <QEvent>
  37 #include <QFontMetrics>
  38 #include <QMouseEvent>
  39 #include <QScrollBar>
  40
  41 #include <libsigrokcxx/libsigrokcxx.hpp>
  42
  43 #include "decodetrace.hpp"
  44 #include "header.hpp"
  45 #include "logicsignal.hpp"
  46 #include "ruler.hpp"
  47 #include "signal.hpp"
  48 #include "tracegroup.hpp"
  49 #include "view.hpp"
  50 #include "viewport.hpp"
  51
  52 #include "pv/session.hpp"
  53 #include "pv/devices/device.hpp"
  54 #include "pv/data/logic.hpp"
  55 #include "pv/data/logicsegment.hpp"
  56 #include "pv/util.hpp"
  57
  58 using boost::shared_lock;
  59 using boost::shared_mutex;
  60
  61 using pv::data::SignalData;
  62 using pv::data::Segment;
  63 using pv::util::format_time;
  64 using pv::util::TimeUnit;
  65
  66 using std::deque;
  67 using std::dynamic_pointer_cast;
  68 using std::inserter;
  69 using std::list;
  70 using std::lock_guard;
  71 using std::max;
  72 using std::make_pair;
  73 using std::min;
  74 using std::pair;
  75 using std::set;
  76 using std::set_difference;
  77 using std::shared_ptr;
  78 using std::unordered_map;
  79 using std::unordered_set;
  80 using std::vector;
  81 using std::weak_ptr;
  82
  83 namespace pv {
  84 namespace view {
  85
  86 const double View::MaxScale = 1e9;
  87 const double View::MinScale = 1e-15;
  88
  89 const int View::MaxScrollValue = INT_MAX / 2;
  90 const int View::MaxViewAutoUpdateRate = 25; // No more than 25 Hz with sticky scrolling
  91
  92 const int View::ScaleUnits[3] = {1, 2, 5};
  93
  94 View::View(Session &session, QWidget *parent) :
  95         QAbstractScrollArea(parent),
  96         session_(session),
  97         viewport_(new Viewport(*this)),
  98         ruler_(new Ruler(*this)),
  99         header_(new Header(*this)),
 100         scale_(1e-3),
 101         offset_(0),
 102         updating_scroll_(false),
 103         sticky_scrolling_(false), // Default setting is set in MainWindow::setup_ui()
 104         always_zoom_to_fit_(false),
 105         tick_period_(0.0),
 106         tick_prefix_(0),
 107         time_unit_(util::Time),
 108         show_cursors_(false),
 109         cursors_(new CursorPair(*this)),
 110         next_flag_text_('A'),
 111         hover_point_(-1, -1)
 112 {
 113         connect(horizontalScrollBar(), SIGNAL(valueChanged(int)),
 114                 this, SLOT(h_scroll_value_changed(int)));
 115         connect(verticalScrollBar(), SIGNAL(valueChanged(int)),
 116                 this, SLOT(v_scroll_value_changed()));
 117
 118         connect(&session_, SIGNAL(signals_changed()),
 119                 this, SLOT(signals_changed()));
 120         connect(&session_, SIGNAL(capture_state_changed(int)),
 121                 this, SLOT(capture_state_updated(int)));
 122         connect(&session_, SIGNAL(data_received()),
 123                 this, SLOT(data_updated()));
 124         connect(&session_, SIGNAL(frame_ended()),
 125                 this, SLOT(data_updated()));
 126
 127         connect(header_, SIGNAL(selection_changed()),
 128                 ruler_, SLOT(clear_selection()));
 129         connect(ruler_, SIGNAL(selection_changed()),
 130                 header_, SLOT(clear_selection()));
 131
 132         connect(header_, SIGNAL(selection_changed()),
 133                 this, SIGNAL(selection_changed()));
 134         connect(ruler_, SIGNAL(selection_changed()),
 135                 this, SIGNAL(selection_changed()));
 136
 137         connect(this, SIGNAL(hover_point_changed()),
 138                 this, SLOT(on_hover_point_changed()));
 139
 140         connect(&lazy_event_handler_, SIGNAL(timeout()),
 141                 this, SLOT(process_sticky_events()));
 142         lazy_event_handler_.setSingleShot(true);
 143
 144         connect(&delayed_view_updater_, SIGNAL(timeout()),
 145                 this, SLOT(perform_delayed_view_update()));
 146         delayed_view_updater_.setSingleShot(true);
 147         delayed_view_updater_.setInterval(1000 / MaxViewAutoUpdateRate);
 148
 149         setViewport(viewport_);
 150
 151         viewport_->installEventFilter(this);
 152         ruler_->installEventFilter(this);
 153         header_->installEventFilter(this);
 154
 155         // Trigger the initial event manually. The default device has signals
 156         // which were created before this object came into being
 157         signals_changed();
 158
 159         // make sure the transparent widgets are on the top
 160         ruler_->raise();
 161         header_->raise();
 162
 163         // Update the zoom state
 164         calculate_tick_spacing();
 165 }
 166
 167 Session& View::session()
 168 {
 169         return session_;
 170 }
 171
 172 const Session& View::session() const
 173 {
 174         return session_;
 175 }
 176
 177 View* View::view()
 178 {
 179         return this;
 180 }
 181
 182 const View* View::view() const
 183 {
 184         return this;
 185 }
 186
 187 Viewport* View::viewport()
 188 {
 189         return viewport_;
 190 }
 191
 192 const Viewport* View::viewport() const
 193 {
 194         return viewport_;
 195 }
 196
 197 vector< shared_ptr<TimeItem> > View::time_items() const
 198 {
 199         const vector<shared_ptr<Flag>> f(flags());
 200         vector<shared_ptr<TimeItem>> items(f.begin(), f.end());
 201         items.push_back(cursors_);
 202         items.push_back(cursors_->first());
 203         items.push_back(cursors_->second());
 204         return items;
 205 }
 206
 207 double View::scale() const
 208 {
 209         return scale_;
 210 }
 211
 212 double View::offset() const
 213 {
 214         return offset_;
 215 }
 216
 217 int View::owner_visual_v_offset() const
 218 {
 219         return -verticalScrollBar()->sliderPosition();
 220 }
 221
 222 void View::set_v_offset(int offset)
 223 {
 224         verticalScrollBar()->setSliderPosition(offset);
 225         header_->update();
 226         viewport_->update();
 227 }
 228
 229 unsigned int View::depth() const
 230 {
 231         return 0;
 232 }
 233
 234 unsigned int View::tick_prefix() const
 235 {
 236         return tick_prefix_;
 237 }
 238
 239 double View::tick_period() const
 240 {
 241         return tick_period_;
 242 }
 243
 244 TimeUnit View::time_unit() const
 245 {
 246         return time_unit_;
 247 }
 248
 249 void View::zoom(double steps)
 250 {
 251         zoom(steps, viewport_->width() / 2);
 252 }
 253
 254 void View::zoom(double steps, int offset)
 255 {
 256         set_zoom(scale_ * pow(3.0/2.0, -steps), offset);
 257 }
 258
 259 void View::zoom_fit(bool gui_state)
 260 {
 261         // Act as one-shot when stopped, toggle along with the GUI otherwise
 262         if (session_.get_capture_state() == Session::Stopped) {
 263                 always_zoom_to_fit_ = false;
 264                 always_zoom_to_fit_changed(false);
 265         } else {
 266                 always_zoom_to_fit_ = gui_state;
 267                 always_zoom_to_fit_changed(gui_state);
 268         }
 269
 270         const pair<double, double> extents = get_time_extents();
 271         const double delta = extents.second - extents.first;
 272         if (delta < 1e-12)
 273                 return;
 274
 275         assert(viewport_);
 276         const int w = viewport_->width();
 277         if (w <= 0)
 278                 return;
 279
 280         const double scale = max(min(delta / w, MaxScale), MinScale);
 281         set_scale_offset(scale, extents.first);
 282 }
 283
 284 void View::zoom_one_to_one()
 285 {
 286         using pv::data::SignalData;
 287
 288         // Make a set of all the visible data objects
 289         set< shared_ptr<SignalData> > visible_data = get_visible_data();
 290         if (visible_data.empty())
 291                 return;
 292
 293         double samplerate = 0.0;
 294         for (const shared_ptr<SignalData> d : visible_data) {
 295                 assert(d);
 296                 const vector< shared_ptr<Segment> > segments =
 297                         d->segments();
 298                 for (const shared_ptr<Segment> &s : segments)
 299                         samplerate = max(samplerate, s->samplerate());
 300         }
 301
 302         if (samplerate == 0.0)
 303                 return;
 304
 305         assert(viewport_);
 306         const int w = viewport_->width();
 307         if (w <= 0)
 308                 return;
 309
 310         set_zoom(1.0 / samplerate, w / 2);
 311 }
 312
 313 void View::set_scale_offset(double scale, double offset)
 314 {
 315         // Disable sticky scrolling / always zoom to fit when acquisition runs
 316         // and user drags the viewport
 317         if ((scale_ == scale) && (offset_ != offset) &&
 318                         (session_.get_capture_state() == Session::Running)) {
 319
 320                 if (sticky_scrolling_) {
 321                         sticky_scrolling_ = false;
 322                         sticky_scrolling_changed(false);
 323                 }
 324
 325                 if (always_zoom_to_fit_) {
 326                         always_zoom_to_fit_ = false;
 327                         always_zoom_to_fit_changed(false);
 328                 }
 329         }
 330
 331         scale_ = scale;
 332         offset_ = offset;
 333
 334         calculate_tick_spacing();
 335
 336         update_scroll();
 337         ruler_->update();
 338         viewport_->update();
 339         scale_offset_changed();
 340 }
 341
 342 set< shared_ptr<SignalData> > View::get_visible_data() const
 343 {
 344         shared_lock<shared_mutex> lock(session().signals_mutex());
 345         const unordered_set< shared_ptr<Signal> > &sigs(session().signals());
 346
 347         // Make a set of all the visible data objects
 348         set< shared_ptr<SignalData> > visible_data;
 349         for (const shared_ptr<Signal> sig : sigs)
 350                 if (sig->enabled())
 351                         visible_data.insert(sig->data());
 352
 353         return visible_data;
 354 }
 355
 356 pair<double, double> View::get_time_extents() const
 357 {
 358         double left_time = DBL_MAX, right_time = DBL_MIN;
 359         const set< shared_ptr<SignalData> > visible_data = get_visible_data();
 360         for (const shared_ptr<SignalData> d : visible_data)
 361         {
 362                 const vector< shared_ptr<Segment> > segments =
 363                         d->segments();
 364                 for (const shared_ptr<Segment> &s : segments) {
 365                         double samplerate = s->samplerate();
 366                         samplerate = (samplerate <= 0.0) ? 1.0 : samplerate;
 367
 368                         const double start_time = s->start_time();
 369                         left_time = min(left_time, start_time);
 370                         right_time = max(right_time, start_time +
 371                                 d->max_sample_count() / samplerate);
 372                 }
 373         }
 374
 375         if (left_time == DBL_MAX && right_time == DBL_MIN)
 376                 return make_pair(0.0, 0.0);
 377
 378         assert(left_time < right_time);
 379         return make_pair(left_time, right_time);
 380 }
 381
 382 void View::enable_sticky_scrolling(bool state)
 383 {
 384         sticky_scrolling_ = state;
 385 }
 386
 387 bool View::cursors_shown() const
 388 {
 389         return show_cursors_;
 390 }
 391
 392 void View::show_cursors(bool show)
 393 {
 394         show_cursors_ = show;
 395         ruler_->update();
 396         viewport_->update();
 397 }
 398
 399 void View::centre_cursors()
 400 {
 401         const double time_width = scale_ * viewport_->width();
 402         cursors_->first()->set_time(offset_ + time_width * 0.4);
 403         cursors_->second()->set_time(offset_ + time_width * 0.6);
 404         ruler_->update();
 405         viewport_->update();
 406 }
 407
 408 std::shared_ptr<CursorPair> View::cursors() const
 409 {
 410         return cursors_;
 411 }
 412
 413 void View::add_flag(double time)
 414 {
 415         flags_.push_back(shared_ptr<Flag>(new Flag(*this, time,
 416                 QString("%1").arg(next_flag_text_))));
 417         next_flag_text_ = (next_flag_text_ >= 'Z') ? 'A' :
 418                 (next_flag_text_ + 1);
 419         time_item_appearance_changed(true, true);
 420 }
 421
 422 void View::remove_flag(std::shared_ptr<Flag> flag)
 423 {
 424         flags_.remove(flag);
 425         time_item_appearance_changed(true, true);
 426 }
 427
 428 vector< std::shared_ptr<Flag> > View::flags() const
 429 {
 430         vector< std::shared_ptr<Flag> > flags(flags_.begin(), flags_.end());
 431         stable_sort(flags.begin(), flags.end(),
 432                 [](const shared_ptr<Flag> &a, const shared_ptr<Flag> &b) {
 433                         return a->time() < b->time();
 434                 });
 435
 436         return flags;
 437 }
 438
 439 const QPoint& View::hover_point() const
 440 {
 441         return hover_point_;
 442 }
 443
 444 void View::update_viewport()
 445 {
 446         assert(viewport_);
 447         viewport_->update();
 448         header_->update();
 449 }
 450
 451 void View::restack_all_row_items()
 452 {
 453         // Make a list of owners that is sorted from deepest first
 454         const auto owners = list_row_item_owners();
 455         vector< RowItemOwner* > sorted_owners(owners.begin(), owners.end());
 456         sort(sorted_owners.begin(), sorted_owners.end(),
 457                 [](const RowItemOwner* a, const RowItemOwner *b) {
 458                         return a->depth() > b->depth(); });
 459
 460         // Restack the items recursively
 461         for (auto &o : sorted_owners)
 462                 o->restack_items();
 463
 464         // Animate the items to their destination
 465         for (const auto &r : *this)
 466                 r->animate_to_layout_v_offset();
 467 }
 468
 469 void View::get_scroll_layout(double &length, double &offset) const
 470 {
 471         const pair<double, double> extents = get_time_extents();
 472         length = (extents.second - extents.first) / scale_;
 473         offset = offset_ / scale_;
 474 }
 475
 476 void View::set_zoom(double scale, int offset)
 477 {
 478         // Reset the "always zoom to fit" feature as the user changed the zoom
 479         always_zoom_to_fit_ = false;
 480         always_zoom_to_fit_changed(false);
 481
 482         const double cursor_offset = offset_ + scale_ * offset;
 483         const double new_scale = max(min(scale, MaxScale), MinScale);
 484         const double new_offset = cursor_offset - new_scale * offset;
 485         set_scale_offset(new_scale, new_offset);
 486 }
 487
 488 void View::calculate_tick_spacing()
 489 {
 490         const double SpacingIncrement = 32.0f;
 491         const double MinValueSpacing = 32.0f;
 492
 493         double min_width = SpacingIncrement, typical_width;
 494
 495         QFontMetrics m(QApplication::font());
 496
 497         do {
 498                 const double min_period = scale_ * min_width;
 499
 500                 const int order = (int)floorf(log10f(min_period));
 501                 const double order_decimal = pow(10.0, order);
 502
 503                 unsigned int unit = 0;
 504
 505                 do {
 506                         tick_period_ = order_decimal * ScaleUnits[unit++];
 507                 } while (tick_period_ < min_period &&
 508                         unit < countof(ScaleUnits));
 509
 510                 tick_prefix_ = (order - pv::util::FirstSIPrefixPower) / 3;
 511
 512                 typical_width = m.boundingRect(0, 0, INT_MAX, INT_MAX,
 513                         Qt::AlignLeft | Qt::AlignTop,
 514                         format_time(offset_, tick_prefix_, time_unit_)).width() +
 515                                 MinValueSpacing;
 516
 517                 min_width += SpacingIncrement;
 518
 519         } while (typical_width > tick_period_ / scale_);
 520 }
 521
 522 void View::update_scroll()
 523 {
 524         assert(viewport_);
 525
 526         const QSize areaSize = viewport_->size();
 527
 528         // Set the horizontal scroll bar
 529         double length = 0, offset = 0;
 530         get_scroll_layout(length, offset);
 531         length = max(length - areaSize.width(), 0.0);
 532
 533         int major_tick_distance = tick_period_ / scale_;
 534
 535         horizontalScrollBar()->setPageStep(areaSize.width() / 2);
 536         horizontalScrollBar()->setSingleStep(major_tick_distance);
 537
 538         updating_scroll_ = true;
 539
 540         if (length < MaxScrollValue) {
 541                 horizontalScrollBar()->setRange(0, length);
 542                 horizontalScrollBar()->setSliderPosition(offset);
 543         } else {
 544                 horizontalScrollBar()->setRange(0, MaxScrollValue);
 545                 horizontalScrollBar()->setSliderPosition(
 546                         offset_ * MaxScrollValue / (scale_ * length));
 547         }
 548
 549         updating_scroll_ = false;
 550
 551         // Set the vertical scrollbar
 552         verticalScrollBar()->setPageStep(areaSize.height());
 553         verticalScrollBar()->setSingleStep(areaSize.height() / 8);
 554
 555         const pair<int, int> extents = v_extents();
 556         verticalScrollBar()->setRange(extents.first - (areaSize.height() / 2),
 557                 extents.second - (areaSize.height() / 2));
 558 }
 559
 560 void View::update_layout()
 561 {
 562         setViewportMargins(
 563                 header_->sizeHint().width() - pv::view::Header::BaselineOffset,
 564                 ruler_->sizeHint().height(), 0, 0);
 565         ruler_->setGeometry(viewport_->x(), 0,
 566                 viewport_->width(), ruler_->extended_size_hint().height());
 567         header_->setGeometry(0, viewport_->y(),
 568                 header_->extended_size_hint().width(), viewport_->height());
 569         update_scroll();
 570 }
 571
 572 void View::paint_label(QPainter &p, const QRect &rect, bool hover)
 573 {
 574         (void)p;
 575         (void)rect;
 576         (void)hover;
 577 }
 578
 579 QRectF View::label_rect(const QRectF &rect)
 580 {
 581         (void)rect;
 582         return QRectF();
 583 }
 584
 585 RowItemOwner* View::find_prevalent_trace_group(
 586         const shared_ptr<sigrok::ChannelGroup> &group,
 587         const unordered_map<shared_ptr<sigrok::Channel>, shared_ptr<Signal> >
 588                 &signal_map)
 589 {
 590         assert(group);
 591
 592         unordered_set<RowItemOwner*> owners;
 593         vector<RowItemOwner*> owner_list;
 594
 595         // Make a set and a list of all the owners
 596         for (const auto &channel : group->channels()) {
 597                 const auto iter = signal_map.find(channel);
 598                 if (iter == signal_map.end())
 599                         continue;
 600
 601                 RowItemOwner *const o = (*iter).second->owner();
 602                 owner_list.push_back(o);
 603                 owners.insert(o);
 604         }
 605
 606         // Iterate through the list of owners, and find the most prevalent
 607         size_t max_prevalence = 0;
 608         RowItemOwner *prevalent_owner = nullptr;
 609         for (RowItemOwner *owner : owners) {
 610                 const size_t prevalence = std::count_if(
 611                         owner_list.begin(), owner_list.end(),
 612                         [&](RowItemOwner *o) { return o == owner; });
 613                 if (prevalence > max_prevalence) {
 614                         max_prevalence = prevalence;
 615                         prevalent_owner = owner;
 616                 }
 617         }
 618
 619         return prevalent_owner;
 620 }
 621
 622 vector< shared_ptr<Trace> > View::extract_new_traces_for_channels(
 623         const vector< shared_ptr<sigrok::Channel> > &channels,
 624         const unordered_map<shared_ptr<sigrok::Channel>, shared_ptr<Signal> >
 625                 &signal_map,
 626         set< shared_ptr<Trace> > &add_list)
 627 {
 628         vector< shared_ptr<Trace> > filtered_traces;
 629
 630         for (const auto &channel : channels)
 631         {
 632                 const auto map_iter = signal_map.find(channel);
 633                 if (map_iter == signal_map.end())
 634                         continue;
 635
 636                 shared_ptr<Trace> trace = (*map_iter).second;
 637                 const auto list_iter = add_list.find(trace);
 638                 if (list_iter == add_list.end())
 639                         continue;
 640
 641                 filtered_traces.push_back(trace);
 642                 add_list.erase(list_iter);
 643         }
 644
 645         return filtered_traces;
 646 }
 647
 648 void View::determine_time_unit()
 649 {
 650         // Check whether we know the sample rate and hence can use time as the unit
 651         if (time_unit_ == util::Samples) {
 652                 shared_lock<shared_mutex> lock(session().signals_mutex());
 653                 const unordered_set< shared_ptr<Signal> > &sigs(session().signals());
 654
 655                 // Check all signals but...
 656                 for (const shared_ptr<Signal> signal : sigs) {
 657                         const shared_ptr<SignalData> data = signal->data();
 658
 659                         // ...only check first segment of each
 660                         const vector< shared_ptr<Segment> > segments = data->segments();
 661                         if (!segments.empty())
 662                                 if (segments[0]->samplerate()) {
 663                                         time_unit_ = util::Time;
 664                                         break;
 665                                 }
 666                 }
 667         }
 668 }
 669
 670 bool View::eventFilter(QObject *object, QEvent *event)
 671 {
 672         const QEvent::Type type = event->type();
 673         if (type == QEvent::MouseMove) {
 674
 675                 const QMouseEvent *const mouse_event = (QMouseEvent*)event;
 676                 if (object == viewport_)
 677                         hover_point_ = mouse_event->pos();
 678                 else if (object == ruler_)
 679                         hover_point_ = QPoint(mouse_event->x(), 0);
 680                 else if (object == header_)
 681                         hover_point_ = QPoint(0, mouse_event->y());
 682                 else
 683                         hover_point_ = QPoint(-1, -1);
 684
 685                 hover_point_changed();
 686
 687         } else if (type == QEvent::Leave) {
 688                 hover_point_ = QPoint(-1, -1);
 689                 hover_point_changed();
 690         }
 691
 692         return QObject::eventFilter(object, event);
 693 }
 694
 695 bool View::viewportEvent(QEvent *e)
 696 {
 697         switch(e->type()) {
 698         case QEvent::Paint:
 699         case QEvent::MouseButtonPress:
 700         case QEvent::MouseButtonRelease:
 701         case QEvent::MouseButtonDblClick:
 702         case QEvent::MouseMove:
 703         case QEvent::Wheel:
 704         case QEvent::TouchBegin:
 705         case QEvent::TouchUpdate:
 706         case QEvent::TouchEnd:
 707                 return false;
 708
 709         default:
 710                 return QAbstractScrollArea::viewportEvent(e);
 711         }
 712 }
 713
 714 void View::resizeEvent(QResizeEvent*)
 715 {
 716         update_layout();
 717 }
 718
 719 void View::row_item_appearance_changed(bool label, bool content)
 720 {
 721         if (label)
 722                 header_->update();
 723         if (content)
 724                 viewport_->update();
 725 }
 726
 727 void View::time_item_appearance_changed(bool label, bool content)
 728 {
 729         if (label)
 730                 ruler_->update();
 731         if (content)
 732                 viewport_->update();
 733 }
 734
 735 void View::extents_changed(bool horz, bool vert)
 736 {
 737         sticky_events_ |=
 738                 (horz ? RowItemHExtentsChanged : 0) |
 739                 (vert ? RowItemVExtentsChanged : 0);
 740         lazy_event_handler_.start();
 741 }
 742
 743 void View::h_scroll_value_changed(int value)
 744 {
 745         if (updating_scroll_)
 746                 return;
 747
 748         // Disable sticky scrolling when user moves the horizontal scroll bar
 749         // during a running acquisition
 750         if (sticky_scrolling_ && (session_.get_capture_state() == Session::Running)) {
 751                 sticky_scrolling_ = false;
 752                 sticky_scrolling_changed(false);
 753         }
 754
 755         const int range = horizontalScrollBar()->maximum();
 756         if (range < MaxScrollValue)
 757                 offset_ = scale_ * value;
 758         else {
 759                 double length = 0, offset;
 760                 get_scroll_layout(length, offset);
 761                 offset_ = scale_ * length * value / MaxScrollValue;
 762         }
 763
 764         ruler_->update();
 765         viewport_->update();
 766 }
 767
 768 void View::v_scroll_value_changed()
 769 {
 770         header_->update();
 771         viewport_->update();
 772 }
 773
 774 void View::signals_changed()
 775 {
 776         vector< shared_ptr<RowItem> > new_top_level_items;
 777
 778         const auto device = session_.device();
 779         if (!device)
 780                 return;
 781
 782         shared_ptr<sigrok::Device> sr_dev = device->device();
 783         assert(sr_dev);
 784
 785         // Make a list of traces that are being added, and a list of traces
 786         // that are being removed
 787         const set<shared_ptr<Trace>> prev_traces = list_by_type<Trace>();
 788
 789         shared_lock<shared_mutex> lock(session_.signals_mutex());
 790         const unordered_set< shared_ptr<Signal> > &sigs(session_.signals());
 791
 792         set< shared_ptr<Trace> > traces(sigs.begin(), sigs.end());
 793
 794 #ifdef ENABLE_DECODE
 795         const vector< shared_ptr<DecodeTrace> > decode_traces(
 796                 session().get_decode_signals());
 797         traces.insert(decode_traces.begin(), decode_traces.end());
 798 #endif
 799
 800         set< shared_ptr<Trace> > add_traces;
 801         set_difference(traces.begin(), traces.end(),
 802                 prev_traces.begin(), prev_traces.end(),
 803                 inserter(add_traces, add_traces.begin()));
 804
 805         set< shared_ptr<Trace> > remove_traces;
 806         set_difference(prev_traces.begin(), prev_traces.end(),
 807                 traces.begin(), traces.end(),
 808                 inserter(remove_traces, remove_traces.begin()));
 809
 810         // Make a look-up table of sigrok Channels to pulseview Signals
 811         unordered_map<shared_ptr<sigrok::Channel>, shared_ptr<Signal> >
 812                 signal_map;
 813         for (const shared_ptr<Signal> &sig : sigs)
 814                 signal_map[sig->channel()] = sig;
 815
 816         // Populate channel groups
 817         for (auto entry : sr_dev->channel_groups())
 818         {
 819                 const shared_ptr<sigrok::ChannelGroup> &group = entry.second;
 820
 821                 if (group->channels().size() <= 1)
 822                         continue;
 823
 824                 // Find best trace group to add to
 825                 RowItemOwner *owner = find_prevalent_trace_group(
 826                         group, signal_map);
 827
 828                 // If there is no trace group, create one
 829                 shared_ptr<TraceGroup> new_trace_group;
 830                 if (!owner) {
 831                         new_trace_group.reset(new TraceGroup());
 832                         owner = new_trace_group.get();
 833                 }
 834
 835                 // Extract traces for the trace group, removing them from
 836                 // the add list
 837                 const vector< shared_ptr<Trace> > new_traces_in_group =
 838                         extract_new_traces_for_channels(group->channels(),
 839                                 signal_map, add_traces);
 840
 841                 // Add the traces to the group
 842                 const pair<int, int> prev_v_extents = owner->v_extents();
 843                 int offset = prev_v_extents.second - prev_v_extents.first;
 844                 for (shared_ptr<Trace> trace : new_traces_in_group) {
 845                         assert(trace);
 846                         owner->add_child_item(trace);
 847
 848                         const pair<int, int> extents = trace->v_extents();
 849                         if (trace->enabled())
 850                                 offset += -extents.first;
 851                         trace->force_to_v_offset(offset);
 852                         if (trace->enabled())
 853                                 offset += extents.second;
 854                 }
 855
 856                 // If this is a new group, enqueue it in the new top level
 857                 // items list
 858                 if (!new_traces_in_group.empty() && new_trace_group)
 859                         new_top_level_items.push_back(new_trace_group);
 860         }
 861
 862         // Enqueue the remaining channels as free ungrouped traces
 863         const vector< shared_ptr<Trace> > new_top_level_signals =
 864                 extract_new_traces_for_channels(sr_dev->channels(),
 865                         signal_map, add_traces);
 866         new_top_level_items.insert(new_top_level_items.end(),
 867                 new_top_level_signals.begin(), new_top_level_signals.end());
 868
 869         // Enqueue any remaining traces i.e. decode traces
 870         new_top_level_items.insert(new_top_level_items.end(),
 871                 add_traces.begin(), add_traces.end());
 872
 873         // Remove any removed traces
 874         for (shared_ptr<Trace> trace : remove_traces) {
 875                 RowItemOwner *const owner = trace->owner();
 876                 assert(owner);
 877                 owner->remove_child_item(trace);
 878         }
 879
 880         // Add and position the pending top levels items
 881         for (auto item : new_top_level_items) {
 882                 add_child_item(item);
 883
 884                 // Position the item after the last present item
 885                 int offset = v_extents().second;
 886                 const pair<int, int> extents = item->v_extents();
 887                 if (item->enabled())
 888                         offset += -extents.first;
 889                 item->force_to_v_offset(offset);
 890                 if (item->enabled())
 891                         offset += extents.second;
 892         }
 893
 894         update_layout();
 895
 896         header_->update();
 897         viewport_->update();
 898 }
 899
 900 void View::capture_state_updated(int state)
 901 {
 902         // Reset "always zoom to fit" when we change to the stopped state
 903         if (always_zoom_to_fit_ && (state == Session::Stopped)) {
 904                 always_zoom_to_fit_ = false;
 905                 always_zoom_to_fit_changed(false);
 906         }
 907
 908         if (state == Session::Running)
 909                 time_unit_ = util::Samples;
 910 }
 911
 912 void View::data_updated()
 913 {
 914         if (always_zoom_to_fit_ || sticky_scrolling_) {
 915                 if (!delayed_view_updater_.isActive())
 916                         delayed_view_updater_.start();
 917         } else {
 918                 determine_time_unit();
 919                 update_scroll();
 920                 ruler_->update();
 921                 viewport_->update();
 922         }
 923 }
 924
 925 void View::perform_delayed_view_update()
 926 {
 927         if (always_zoom_to_fit_)
 928                 zoom_fit(true);
 929
 930         if (sticky_scrolling_) {
 931                 // Make right side of the view sticky
 932                 double length = 0, offset;
 933                 get_scroll_layout(length, offset);
 934
 935                 const QSize areaSize = viewport_->size();
 936                 length = max(length - areaSize.width(), 0.0);
 937
 938                 offset_ = scale_ * length;
 939         }
 940
 941         determine_time_unit();
 942         update_scroll();
 943         ruler_->update();
 944         viewport_->update();
 945 }
 946
 947 void View::process_sticky_events()
 948 {
 949         if (sticky_events_ & RowItemHExtentsChanged)
 950                 update_layout();
 951         if (sticky_events_ & RowItemVExtentsChanged) {
 952                 restack_all_row_items();
 953                 update_scroll();
 954         }
 955
 956         // Clear the sticky events
 957         sticky_events_ = 0;
 958 }
 959
 960 void View::on_hover_point_changed()
 961 {
 962         for (shared_ptr<RowItem> r : *this)
 963                 r->hover_point_changed();
 964 }
 965
 966 } // namespace view
 967 } // namespace pv