]> sigrok.org Git - pulseview.git/blobdiff - pv/view/view.cpp
Provide short-term fix for #627 by limiting zoom range to 100 ps
[pulseview.git] / pv / view / view.cpp
index 28408eee39db4723497d906ae8a21b02e901427d..fdb9354b9315cefe4c4a06d23b00a879db7bab82 100644 (file)
 
 #include <extdef.h>
 
+#include <algorithm>
 #include <cassert>
 #include <climits>
 #include <cmath>
+#include <iterator>
 #include <mutex>
 #include <unordered_set>
 
@@ -36,9 +38,8 @@
 #include <QMouseEvent>
 #include <QScrollBar>
 
-#include <libsigrok/libsigrok.hpp>
+#include <libsigrokcxx/libsigrokcxx.hpp>
 
-#include "cursorheader.hpp"
 #include "decodetrace.hpp"
 #include "header.hpp"
 #include "logicsignal.hpp"
@@ -49,6 +50,7 @@
 #include "viewport.hpp"
 
 #include "pv/session.hpp"
+#include "pv/devices/device.hpp"
 #include "pv/data/logic.hpp"
 #include "pv/data/logicsegment.hpp"
 #include "pv/util.hpp"
@@ -59,10 +61,11 @@ using boost::shared_mutex;
 using pv::data::SignalData;
 using pv::data::Segment;
 using pv::util::format_time;
+using pv::util::TimeUnit;
 
-using std::back_inserter;
 using std::deque;
 using std::dynamic_pointer_cast;
+using std::inserter;
 using std::list;
 using std::lock_guard;
 using std::max;
@@ -70,6 +73,7 @@ using std::make_pair;
 using std::min;
 using std::pair;
 using std::set;
+using std::set_difference;
 using std::shared_ptr;
 using std::unordered_map;
 using std::unordered_set;
@@ -80,63 +84,55 @@ namespace pv {
 namespace view {
 
 const double View::MaxScale = 1e9;
-const double View::MinScale = 1e-15;
+const double View::MinScale = 1e-12;
 
 const int View::MaxScrollValue = INT_MAX / 2;
+const int View::MaxViewAutoUpdateRate = 25; // No more than 25 Hz with sticky scrolling
 
 const int View::ScaleUnits[3] = {1, 2, 5};
 
-const QColor View::CursorAreaColour(220, 231, 243);
-
-const QSizeF View::LabelPadding(4, 0);
-
 View::View(Session &session, QWidget *parent) :
        QAbstractScrollArea(parent),
        session_(session),
        viewport_(new Viewport(*this)),
        ruler_(new Ruler(*this)),
-       cursorheader_(new CursorHeader(*this)),
        header_(new Header(*this)),
-       scale_(1e-6),
+       scale_(1e-3),
        offset_(0),
-       v_offset_(0),
        updating_scroll_(false),
+       sticky_scrolling_(false), // Default setting is set in MainWindow::setup_ui()
+       always_zoom_to_fit_(false),
        tick_period_(0.0),
        tick_prefix_(0),
+       tick_precision_(0),
+       time_unit_(util::Time),
        show_cursors_(false),
-       cursors_(*this),
+       cursors_(new CursorPair(*this)),
+       next_flag_text_('A'),
        hover_point_(-1, -1)
 {
        connect(horizontalScrollBar(), SIGNAL(valueChanged(int)),
                this, SLOT(h_scroll_value_changed(int)));
        connect(verticalScrollBar(), SIGNAL(valueChanged(int)),
-               this, SLOT(v_scroll_value_changed(int)));
+               this, SLOT(v_scroll_value_changed()));
 
        connect(&session_, SIGNAL(signals_changed()),
                this, SLOT(signals_changed()));
        connect(&session_, SIGNAL(capture_state_changed(int)),
-               this, SLOT(data_updated()));
+               this, SLOT(capture_state_updated(int)));
        connect(&session_, SIGNAL(data_received()),
                this, SLOT(data_updated()));
        connect(&session_, SIGNAL(frame_ended()),
                this, SLOT(data_updated()));
 
-       connect(cursors_.first().get(), SIGNAL(time_changed()),
-               this, SLOT(marker_time_changed()));
-       connect(cursors_.second().get(), SIGNAL(time_changed()),
-               this, SLOT(marker_time_changed()));
-
-       connect(header_, SIGNAL(signals_moved()),
-               this, SLOT(on_signals_moved()));
-
        connect(header_, SIGNAL(selection_changed()),
-               cursorheader_, SLOT(clear_selection()));
-       connect(cursorheader_, SIGNAL(selection_changed()),
+               ruler_, SLOT(clear_selection()));
+       connect(ruler_, SIGNAL(selection_changed()),
                header_, SLOT(clear_selection()));
 
        connect(header_, SIGNAL(selection_changed()),
                this, SIGNAL(selection_changed()));
-       connect(cursorheader_, SIGNAL(selection_changed()),
+       connect(ruler_, SIGNAL(selection_changed()),
                this, SIGNAL(selection_changed()));
 
        connect(this, SIGNAL(hover_point_changed()),
@@ -146,11 +142,15 @@ View::View(Session &session, QWidget *parent) :
                this, SLOT(process_sticky_events()));
        lazy_event_handler_.setSingleShot(true);
 
+       connect(&delayed_view_updater_, SIGNAL(timeout()),
+               this, SLOT(perform_delayed_view_update()));
+       delayed_view_updater_.setSingleShot(true);
+       delayed_view_updater_.setInterval(1000 / MaxViewAutoUpdateRate);
+
        setViewport(viewport_);
 
        viewport_->installEventFilter(this);
        ruler_->installEventFilter(this);
-       cursorheader_->installEventFilter(this);
        header_->installEventFilter(this);
 
        // Trigger the initial event manually. The default device has signals
@@ -158,7 +158,7 @@ View::View(Session &session, QWidget *parent) :
        signals_changed();
 
        // make sure the transparent widgets are on the top
-       cursorheader_->raise();
+       ruler_->raise();
        header_->raise();
 
        // Update the zoom state
@@ -197,9 +197,11 @@ const Viewport* View::viewport() const
 
 vector< shared_ptr<TimeItem> > View::time_items() const
 {
-       vector< shared_ptr<TimeItem> > items;
-       items.push_back(cursors_.first());
-       items.push_back(cursors_.second());
+       const vector<shared_ptr<Flag>> f(flags());
+       vector<shared_ptr<TimeItem>> items(f.begin(), f.end());
+       items.push_back(cursors_);
+       items.push_back(cursors_->first());
+       items.push_back(cursors_->second());
        return items;
 }
 
@@ -215,7 +217,14 @@ double View::offset() const
 
 int View::owner_visual_v_offset() const
 {
-       return -v_offset_;
+       return -verticalScrollBar()->sliderPosition();
+}
+
+void View::set_v_offset(int offset)
+{
+       verticalScrollBar()->setSliderPosition(offset);
+       header_->update();
+       viewport_->update();
 }
 
 unsigned int View::depth() const
@@ -228,11 +237,21 @@ unsigned int View::tick_prefix() const
        return tick_prefix_;
 }
 
+unsigned int View::tick_precision() const
+{
+       return tick_precision_;
+}
+
 double View::tick_period() const
 {
        return tick_period_;
 }
 
+TimeUnit View::time_unit() const
+{
+       return time_unit_;
+}
+
 void View::zoom(double steps)
 {
        zoom(steps, viewport_->width() / 2);
@@ -243,8 +262,17 @@ void View::zoom(double steps, int offset)
        set_zoom(scale_ * pow(3.0/2.0, -steps), offset);
 }
 
-void View::zoom_fit()
+void View::zoom_fit(bool gui_state)
 {
+       // Act as one-shot when stopped, toggle along with the GUI otherwise
+       if (session_.get_capture_state() == Session::Stopped) {
+               always_zoom_to_fit_ = false;
+               always_zoom_to_fit_changed(false);
+       } else {
+               always_zoom_to_fit_ = gui_state;
+               always_zoom_to_fit_changed(gui_state);
+       }
+
        const pair<double, double> extents = get_time_extents();
        const double delta = extents.second - extents.first;
        if (delta < 1e-12)
@@ -290,6 +318,22 @@ void View::zoom_one_to_one()
 
 void View::set_scale_offset(double scale, double offset)
 {
+       // Disable sticky scrolling / always zoom to fit when acquisition runs
+       // and user drags the viewport
+       if ((scale_ == scale) && (offset_ != offset) &&
+                       (session_.get_capture_state() == Session::Running)) {
+
+               if (sticky_scrolling_) {
+                       sticky_scrolling_ = false;
+                       sticky_scrolling_changed(false);
+               }
+
+               if (always_zoom_to_fit_) {
+                       always_zoom_to_fit_ = false;
+                       always_zoom_to_fit_changed(false);
+               }
+       }
+
        scale_ = scale;
        offset_ = offset;
 
@@ -297,7 +341,6 @@ void View::set_scale_offset(double scale, double offset)
 
        update_scroll();
        ruler_->update();
-       cursorheader_->update();
        viewport_->update();
        scale_offset_changed();
 }
@@ -305,7 +348,7 @@ void View::set_scale_offset(double scale, double offset)
 set< shared_ptr<SignalData> > View::get_visible_data() const
 {
        shared_lock<shared_mutex> lock(session().signals_mutex());
-       const vector< shared_ptr<Signal> > &sigs(session().signals());
+       const unordered_set< shared_ptr<Signal> > &sigs(session().signals());
 
        // Make a set of all the visible data objects
        set< shared_ptr<SignalData> > visible_data;
@@ -331,7 +374,7 @@ pair<double, double> View::get_time_extents() const
                        const double start_time = s->start_time();
                        left_time = min(left_time, start_time);
                        right_time = max(right_time, start_time +
-                               d->get_max_sample_count() / samplerate);
+                               d->max_sample_count() / samplerate);
                }
        }
 
@@ -342,6 +385,11 @@ pair<double, double> View::get_time_extents() const
        return make_pair(left_time, right_time);
 }
 
+void View::enable_sticky_scrolling(bool state)
+{
+       sticky_scrolling_ = state;
+}
+
 bool View::cursors_shown() const
 {
        return show_cursors_;
@@ -350,27 +398,48 @@ bool View::cursors_shown() const
 void View::show_cursors(bool show)
 {
        show_cursors_ = show;
-       cursorheader_->update();
+       ruler_->update();
        viewport_->update();
 }
 
 void View::centre_cursors()
 {
        const double time_width = scale_ * viewport_->width();
-       cursors_.first()->set_time(offset_ + time_width * 0.4);
-       cursors_.second()->set_time(offset_ + time_width * 0.6);
-       cursorheader_->update();
+       cursors_->first()->set_time(offset_ + time_width * 0.4);
+       cursors_->second()->set_time(offset_ + time_width * 0.6);
+       ruler_->update();
        viewport_->update();
 }
 
-CursorPair& View::cursors()
+std::shared_ptr<CursorPair> View::cursors() const
 {
        return cursors_;
 }
 
-const CursorPair& View::cursors() const
+void View::add_flag(double time)
 {
-       return cursors_;
+       flags_.push_back(shared_ptr<Flag>(new Flag(*this, time,
+               QString("%1").arg(next_flag_text_))));
+       next_flag_text_ = (next_flag_text_ >= 'Z') ? 'A' :
+               (next_flag_text_ + 1);
+       time_item_appearance_changed(true, true);
+}
+
+void View::remove_flag(std::shared_ptr<Flag> flag)
+{
+       flags_.remove(flag);
+       time_item_appearance_changed(true, true);
+}
+
+vector< std::shared_ptr<Flag> > View::flags() const
+{
+       vector< std::shared_ptr<Flag> > flags(flags_.begin(), flags_.end());
+       stable_sort(flags.begin(), flags.end(),
+               [](const shared_ptr<Flag> &a, const shared_ptr<Flag> &b) {
+                       return a->time() < b->time();
+               });
+
+       return flags;
 }
 
 const QPoint& View::hover_point() const
@@ -387,12 +456,8 @@ void View::update_viewport()
 
 void View::restack_all_row_items()
 {
-       // Make a set of owners
-       unordered_set< RowItemOwner* > owners;
-       for (const auto &r : *this)
-               owners.insert(r->owner());
-
-       // Make a list that is sorted from deepest first
+       // Make a list of owners that is sorted from deepest first
+       const auto owners = list_row_item_owners();
        vector< RowItemOwner* > sorted_owners(owners.begin(), owners.end());
        sort(sorted_owners.begin(), sorted_owners.end(),
                [](const RowItemOwner* a, const RowItemOwner *b) {
@@ -416,6 +481,10 @@ void View::get_scroll_layout(double &length, double &offset) const
 
 void View::set_zoom(double scale, int offset)
 {
+       // Reset the "always zoom to fit" feature as the user changed the zoom
+       always_zoom_to_fit_ = false;
+       always_zoom_to_fit_changed(false);
+
        const double cursor_offset = offset_ + scale_ * offset;
        const double new_scale = max(min(scale, MaxScale), MinScale);
        const double new_offset = cursor_offset - new_scale * offset;
@@ -424,10 +493,16 @@ void View::set_zoom(double scale, int offset)
 
 void View::calculate_tick_spacing()
 {
-       const double SpacingIncrement = 32.0f;
-       const double MinValueSpacing = 32.0f;
+       const double SpacingIncrement = 10.0f;
+       const double MinValueSpacing = 25.0f;
 
-       double min_width = SpacingIncrement, typical_width;
+       // Figure out the highest numeric value visible on a label
+       const QSize areaSize = viewport_->size();
+       const double max_time = max(fabs(offset_),
+               fabs(offset_ + scale_ * areaSize.width()));
+
+       double min_width = SpacingIncrement;
+       double label_width, tick_period_width;
 
        QFontMetrics m(QApplication::font());
 
@@ -437,23 +512,37 @@ void View::calculate_tick_spacing()
                const int order = (int)floorf(log10f(min_period));
                const double order_decimal = pow(10.0, order);
 
+               // Allow for a margin of error so that a scale unit of 1 can be used.
+               // Otherwise, for a SU of 1 the tick period will almost always be below
+               // the min_period by a small amount - and thus skipped in favor of 2.
+               // Note: margin assumes that SU[0] and SU[1] contain the smallest values
+               double tp_margin = (ScaleUnits[0] + ScaleUnits[1]) / 2.0;
+               double tp_with_margin;
                unsigned int unit = 0;
 
                do {
-                       tick_period_ = order_decimal * ScaleUnits[unit++];
-               } while (tick_period_ < min_period &&
-                       unit < countof(ScaleUnits));
+                       tp_with_margin = order_decimal * (ScaleUnits[unit++] + tp_margin);
+               } while (tp_with_margin < min_period && unit < countof(ScaleUnits));
 
+               tick_period_ = order_decimal * ScaleUnits[unit - 1];
                tick_prefix_ = (order - pv::util::FirstSIPrefixPower) / 3;
 
-               typical_width = m.boundingRect(0, 0, INT_MAX, INT_MAX,
-                       Qt::AlignLeft | Qt::AlignTop,
-                       format_time(offset_, tick_prefix_)).width() +
+               // Precision is the number of fractional digits required, not
+               // taking the prefix into account (and it must never be negative)
+               tick_precision_ = std::max((int)ceil(log10f(1 / tick_period_)), 0);
+
+               tick_period_width = tick_period_ / scale_;
+
+               const QString label_text =
+                       format_time(max_time, tick_prefix_, time_unit_, tick_precision_);
+
+               label_width = m.boundingRect(0, 0, INT_MAX, INT_MAX,
+                       Qt::AlignLeft | Qt::AlignTop, label_text).width() +
                                MinValueSpacing;
 
                min_width += SpacingIncrement;
 
-       } while(typical_width > tick_period_ / scale_);
+       } while (tick_period_width < label_width);
 }
 
 void View::update_scroll()
@@ -487,11 +576,11 @@ void View::update_scroll()
 
        // Set the vertical scrollbar
        verticalScrollBar()->setPageStep(areaSize.height());
+       verticalScrollBar()->setSingleStep(areaSize.height() / 8);
 
        const pair<int, int> extents = v_extents();
-       const int extra_scroll_height = (extents.second - extents.first) / 4;
-       verticalScrollBar()->setRange(extents.first - extra_scroll_height,
-               extents.first + extra_scroll_height);
+       verticalScrollBar()->setRange(extents.first - (areaSize.height() / 2),
+               extents.second - (areaSize.height() / 2));
 }
 
 void View::update_layout()
@@ -500,66 +589,108 @@ void View::update_layout()
                header_->sizeHint().width() - pv::view::Header::BaselineOffset,
                ruler_->sizeHint().height(), 0, 0);
        ruler_->setGeometry(viewport_->x(), 0,
-               viewport_->width(), viewport_->y());
-       cursorheader_->setGeometry(
-               viewport_->x(),
-               ruler_->sizeHint().height() - cursorheader_->sizeHint().height() / 2,
-               viewport_->width(), cursorheader_->sizeHint().height());
+               viewport_->width(), ruler_->extended_size_hint().height());
        header_->setGeometry(0, viewport_->y(),
-               header_->sizeHint().width(), viewport_->height());
+               header_->extended_size_hint().width(), viewport_->height());
        update_scroll();
 }
 
-void View::paint_label(QPainter &p, int right, bool hover)
+void View::paint_label(QPainter &p, const QRect &rect, bool hover)
 {
        (void)p;
-       (void)right;
+       (void)rect;
        (void)hover;
 }
 
-QRectF View::label_rect(int right)
+QRectF View::label_rect(const QRectF &rect)
 {
-       (void)right;
+       (void)rect;
        return QRectF();
 }
 
-bool View::add_channels_to_owner(
+RowItemOwner* View::find_prevalent_trace_group(
+       const shared_ptr<sigrok::ChannelGroup> &group,
+       const unordered_map<shared_ptr<sigrok::Channel>, shared_ptr<Signal> >
+               &signal_map)
+{
+       assert(group);
+
+       unordered_set<RowItemOwner*> owners;
+       vector<RowItemOwner*> owner_list;
+
+       // Make a set and a list of all the owners
+       for (const auto &channel : group->channels()) {
+               const auto iter = signal_map.find(channel);
+               if (iter == signal_map.end())
+                       continue;
+
+               RowItemOwner *const o = (*iter).second->owner();
+               owner_list.push_back(o);
+               owners.insert(o);
+       }
+
+       // Iterate through the list of owners, and find the most prevalent
+       size_t max_prevalence = 0;
+       RowItemOwner *prevalent_owner = nullptr;
+       for (RowItemOwner *owner : owners) {
+               const size_t prevalence = std::count_if(
+                       owner_list.begin(), owner_list.end(),
+                       [&](RowItemOwner *o) { return o == owner; });
+               if (prevalence > max_prevalence) {
+                       max_prevalence = prevalence;
+                       prevalent_owner = owner;
+               }
+       }
+
+       return prevalent_owner;
+}
+
+vector< shared_ptr<Trace> > View::extract_new_traces_for_channels(
        const vector< shared_ptr<sigrok::Channel> > &channels,
-       RowItemOwner *owner, int &offset,
-       unordered_map<shared_ptr<sigrok::Channel>, shared_ptr<Signal> >
+       const unordered_map<shared_ptr<sigrok::Channel>, shared_ptr<Signal> >
                &signal_map,
-       std::function<bool (shared_ptr<RowItem>)> filter_func)
+       set< shared_ptr<Trace> > &add_list)
 {
-       bool any_added = false;
-
-       assert(owner);
+       vector< shared_ptr<Trace> > filtered_traces;
 
        for (const auto &channel : channels)
        {
-               const auto iter = signal_map.find(channel);
-               if (iter == signal_map.end() ||
-                       (filter_func && !filter_func((*iter).second)))
+               const auto map_iter = signal_map.find(channel);
+               if (map_iter == signal_map.end())
                        continue;
 
-               shared_ptr<RowItem> row_item = (*iter).second;
-               owner->add_child_item(row_item);
-               apply_offset(row_item, offset);
-               signal_map.erase(iter);
+               shared_ptr<Trace> trace = (*map_iter).second;
+               const auto list_iter = add_list.find(trace);
+               if (list_iter == add_list.end())
+                       continue;
 
-               any_added = true;
+               filtered_traces.push_back(trace);
+               add_list.erase(list_iter);
        }
 
-       return any_added;
+       return filtered_traces;
 }
 
-void View::apply_offset(shared_ptr<RowItem> row_item, int &offset) {
-       assert(row_item);
-       const pair<int, int> extents = row_item->v_extents();
-       if (row_item->enabled())
-               offset += -extents.first;
-       row_item->force_to_v_offset(offset);
-       if (row_item->enabled())
-               offset += extents.second;
+void View::determine_time_unit()
+{
+       // Check whether we know the sample rate and hence can use time as the unit
+       if (time_unit_ == util::Samples) {
+               shared_lock<shared_mutex> lock(session().signals_mutex());
+               const unordered_set< shared_ptr<Signal> > &sigs(session().signals());
+
+               // Check all signals but...
+               for (const shared_ptr<Signal> signal : sigs) {
+                       const shared_ptr<SignalData> data = signal->data();
+
+                       // ...only check first segment of each
+                       const vector< shared_ptr<Segment> > segments = data->segments();
+                       if (!segments.empty())
+                               if (segments[0]->samplerate()) {
+                                       time_unit_ = util::Time;
+                                       break;
+                               }
+               }
+       }
 }
 
 bool View::eventFilter(QObject *object, QEvent *event)
@@ -570,7 +701,7 @@ bool View::eventFilter(QObject *object, QEvent *event)
                const QMouseEvent *const mouse_event = (QMouseEvent*)event;
                if (object == viewport_)
                        hover_point_ = mouse_event->pos();
-               else if (object == ruler_ || object == cursorheader_)
+               else if (object == ruler_)
                        hover_point_ = QPoint(mouse_event->x(), 0);
                else if (object == header_)
                        hover_point_ = QPoint(0, mouse_event->y());
@@ -611,7 +742,7 @@ void View::resizeEvent(QResizeEvent*)
        update_layout();
 }
 
-void View::appearance_changed(bool label, bool content)
+void View::row_item_appearance_changed(bool label, bool content)
 {
        if (label)
                header_->update();
@@ -619,11 +750,19 @@ void View::appearance_changed(bool label, bool content)
                viewport_->update();
 }
 
+void View::time_item_appearance_changed(bool label, bool content)
+{
+       if (label)
+               ruler_->update();
+       if (content)
+               viewport_->update();
+}
+
 void View::extents_changed(bool horz, bool vert)
 {
        sticky_events_ |=
-               (horz ? SelectableItemHExtentsChanged : 0) |
-               (vert ? SelectableItemVExtentsChanged : 0);
+               (horz ? RowItemHExtentsChanged : 0) |
+               (vert ? RowItemVExtentsChanged : 0);
        lazy_event_handler_.start();
 }
 
@@ -632,6 +771,13 @@ void View::h_scroll_value_changed(int value)
        if (updating_scroll_)
                return;
 
+       // Disable sticky scrolling when user moves the horizontal scroll bar
+       // during a running acquisition
+       if (sticky_scrolling_ && (session_.get_capture_state() == Session::Running)) {
+               sticky_scrolling_ = false;
+               sticky_scrolling_changed(false);
+       }
+
        const int range = horizontalScrollBar()->maximum();
        if (range < MaxScrollValue)
                offset_ = scale_ * value;
@@ -642,114 +788,196 @@ void View::h_scroll_value_changed(int value)
        }
 
        ruler_->update();
-       cursorheader_->update();
        viewport_->update();
 }
 
-void View::v_scroll_value_changed(int value)
+void View::v_scroll_value_changed()
 {
-       v_offset_ = value;
        header_->update();
        viewport_->update();
 }
 
 void View::signals_changed()
 {
-       int offset = 0;
+       vector< shared_ptr<RowItem> > new_top_level_items;
 
-       // Populate the traces
-       clear_child_items();
+       const auto device = session_.device();
+       if (!device)
+               return;
 
-       shared_ptr<sigrok::Device> device = session_.device();
-       assert(device);
+       shared_ptr<sigrok::Device> sr_dev = device->device();
+       assert(sr_dev);
 
-       // Collect a set of signals
-       unordered_map<shared_ptr<sigrok::Channel>, shared_ptr<Signal> >
-               signal_map;
+       // Make a list of traces that are being added, and a list of traces
+       // that are being removed
+       const set<shared_ptr<Trace>> prev_traces = list_by_type<Trace>();
 
        shared_lock<shared_mutex> lock(session_.signals_mutex());
-       const vector< shared_ptr<Signal> > &sigs(session_.signals());
+       const unordered_set< shared_ptr<Signal> > &sigs(session_.signals());
+
+       set< shared_ptr<Trace> > traces(sigs.begin(), sigs.end());
 
+#ifdef ENABLE_DECODE
+       const vector< shared_ptr<DecodeTrace> > decode_traces(
+               session().get_decode_signals());
+       traces.insert(decode_traces.begin(), decode_traces.end());
+#endif
+
+       set< shared_ptr<Trace> > add_traces;
+       set_difference(traces.begin(), traces.end(),
+               prev_traces.begin(), prev_traces.end(),
+               inserter(add_traces, add_traces.begin()));
+
+       set< shared_ptr<Trace> > remove_traces;
+       set_difference(prev_traces.begin(), prev_traces.end(),
+               traces.begin(), traces.end(),
+               inserter(remove_traces, remove_traces.begin()));
+
+       // Make a look-up table of sigrok Channels to pulseview Signals
+       unordered_map<shared_ptr<sigrok::Channel>, shared_ptr<Signal> >
+               signal_map;
        for (const shared_ptr<Signal> &sig : sigs)
                signal_map[sig->channel()] = sig;
 
        // Populate channel groups
-       for (auto entry : device->channel_groups())
+       for (auto entry : sr_dev->channel_groups())
        {
                const shared_ptr<sigrok::ChannelGroup> &group = entry.second;
 
                if (group->channels().size() <= 1)
                        continue;
 
-               shared_ptr<TraceGroup> trace_group(new TraceGroup());
-               int child_offset = 0;
-               if (add_channels_to_owner(group->channels(),
-                       trace_group.get(), child_offset, signal_map))
-               {
-                       add_child_item(trace_group);
-                       apply_offset(trace_group, offset);
-               }
-       }
+               // Find best trace group to add to
+               RowItemOwner *owner = find_prevalent_trace_group(
+                       group, signal_map);
 
-       // Add the remaining logic channels
-       shared_ptr<TraceGroup> logic_trace_group(new TraceGroup());
-       int child_offset = 0;
+               // If there is no trace group, create one
+               shared_ptr<TraceGroup> new_trace_group;
+               if (!owner) {
+                       new_trace_group.reset(new TraceGroup());
+                       owner = new_trace_group.get();
+               }
 
-       if (add_channels_to_owner(device->channels(),
-               logic_trace_group.get(), child_offset, signal_map,
-               [](shared_ptr<RowItem> r) -> bool {
-                       return dynamic_pointer_cast<LogicSignal>(r) != nullptr;
-                       }))
+               // Extract traces for the trace group, removing them from
+               // the add list
+               const vector< shared_ptr<Trace> > new_traces_in_group =
+                       extract_new_traces_for_channels(group->channels(),
+                               signal_map, add_traces);
+
+               // Add the traces to the group
+               const pair<int, int> prev_v_extents = owner->v_extents();
+               int offset = prev_v_extents.second - prev_v_extents.first;
+               for (shared_ptr<Trace> trace : new_traces_in_group) {
+                       assert(trace);
+                       owner->add_child_item(trace);
+
+                       const pair<int, int> extents = trace->v_extents();
+                       if (trace->enabled())
+                               offset += -extents.first;
+                       trace->force_to_v_offset(offset);
+                       if (trace->enabled())
+                               offset += extents.second;
+               }
 
-       {
-               add_child_item(logic_trace_group);
-               apply_offset(logic_trace_group, offset);
+               // If this is a new group, enqueue it in the new top level
+               // items list
+               if (!new_traces_in_group.empty() && new_trace_group)
+                       new_top_level_items.push_back(new_trace_group);
        }
 
-       // Add the remaining channels
-       add_channels_to_owner(device->channels(), this, offset, signal_map);
-       assert(signal_map.empty());
+       // Enqueue the remaining channels as free ungrouped traces
+       const vector< shared_ptr<Trace> > new_top_level_signals =
+               extract_new_traces_for_channels(sr_dev->channels(),
+                       signal_map, add_traces);
+       new_top_level_items.insert(new_top_level_items.end(),
+               new_top_level_signals.begin(), new_top_level_signals.end());
+
+       // Enqueue any remaining traces i.e. decode traces
+       new_top_level_items.insert(new_top_level_items.end(),
+               add_traces.begin(), add_traces.end());
+
+       // Remove any removed traces
+       for (shared_ptr<Trace> trace : remove_traces) {
+               RowItemOwner *const owner = trace->owner();
+               assert(owner);
+               owner->remove_child_item(trace);
+       }
 
-       // Add decode signals
-#ifdef ENABLE_DECODE
-       const vector< shared_ptr<DecodeTrace> > decode_sigs(
-               session().get_decode_signals());
-       for (auto s : decode_sigs) {
-               add_child_item(s);
-               apply_offset(s, offset);
+       // Add and position the pending top levels items
+       for (auto item : new_top_level_items) {
+               add_child_item(item);
+
+               // Position the item after the last present item
+               int offset = v_extents().second;
+               const pair<int, int> extents = item->v_extents();
+               if (item->enabled())
+                       offset += -extents.first;
+               item->force_to_v_offset(offset);
+               if (item->enabled())
+                       offset += extents.second;
        }
-#endif
 
        update_layout();
+
+       header_->update();
+       viewport_->update();
 }
 
-void View::data_updated()
+void View::capture_state_updated(int state)
 {
-       // Update the scroll bars
-       update_scroll();
+       // Reset "always zoom to fit" when we change to the stopped state
+       if (always_zoom_to_fit_ && (state == Session::Stopped)) {
+               always_zoom_to_fit_ = false;
+               always_zoom_to_fit_changed(false);
+       }
 
-       // Repaint the view
-       viewport_->update();
+       if (state == Session::Running)
+               time_unit_ = util::Samples;
 }
 
-void View::marker_time_changed()
+void View::data_updated()
 {
-       cursorheader_->update();
-       viewport_->update();
+       if (always_zoom_to_fit_ || sticky_scrolling_) {
+               if (!delayed_view_updater_.isActive())
+                       delayed_view_updater_.start();
+       } else {
+               determine_time_unit();
+               update_scroll();
+               ruler_->update();
+               viewport_->update();
+       }
 }
 
-void View::on_signals_moved()
+void View::perform_delayed_view_update()
 {
+       if (always_zoom_to_fit_)
+               zoom_fit(true);
+
+       if (sticky_scrolling_) {
+               // Make right side of the view sticky
+               double length = 0, offset;
+               get_scroll_layout(length, offset);
+
+               const QSize areaSize = viewport_->size();
+               length = max(length - areaSize.width(), 0.0);
+
+               offset_ = scale_ * length;
+       }
+
+       determine_time_unit();
        update_scroll();
-       signals_moved();
+       ruler_->update();
+       viewport_->update();
 }
 
 void View::process_sticky_events()
 {
-       if (sticky_events_ & SelectableItemHExtentsChanged)
+       if (sticky_events_ & RowItemHExtentsChanged)
                update_layout();
-       if (sticky_events_ & SelectableItemVExtentsChanged)
+       if (sticky_events_ & RowItemVExtentsChanged) {
                restack_all_row_items();
+               update_scroll();
+       }
 
        // Clear the sticky events
        sticky_events_ = 0;