Fix random clazy warnings
[pulseview.git] / pv / views / trace / analogsignal.cpp
index 90e441e09f125392c5ccd215e0b2441b55f3c026..ae3fe8d28e20e1dfd5c1802b473e9018d0bf7e9a 100644 (file)
@@ -38,6 +38,7 @@
 #include "logicsignal.hpp"
 #include "view.hpp"
 
+#include "pv/util.hpp"
 #include "pv/data/analog.hpp"
 #include "pv/data/analogsegment.hpp"
 #include "pv/data/logic.hpp"
 
 #include <libsigrokcxx/libsigrokcxx.hpp>
 
-using std::bind;
 using std::deque;
 using std::div;
 using std::div_t;
+// Note that "using std::isnan;" is _not_ put here since that would break
+// compilation on some platforms. Use "std::isnan()" instead in checks below.
 using std::max;
 using std::make_pair;
 using std::min;
 using std::numeric_limits;
 using std::out_of_range;
 using std::pair;
-using std::placeholders::_1;
 using std::shared_ptr;
 using std::vector;
 
+using pv::data::LogicSegment;
 using pv::data::SignalBase;
+using pv::util::SIPrefix;
 
 namespace pv {
 namespace views {
 namespace trace {
 
-const QColor AnalogSignal::SignalColours[4] = {
+const QColor AnalogSignal::SignalColors[4] = {
        QColor(0xC4, 0xA0, 0x00),       // Yellow
        QColor(0x87, 0x20, 0x7A),       // Magenta
        QColor(0x20, 0x4A, 0x87),       // Blue
@@ -78,10 +81,10 @@ const QPen AnalogSignal::AxisPen(QColor(0, 0, 0, 30 * 256 / 100), 2);
 const QColor AnalogSignal::GridMajorColor = QColor(0, 0, 0, 40 * 256 / 100);
 const QColor AnalogSignal::GridMinorColor = QColor(0, 0, 0, 20 * 256 / 100);
 
-const QColor AnalogSignal::SamplingPointColour(0x77, 0x77, 0x77);
-const QColor AnalogSignal::SamplingPointColourLo = QColor(200, 0, 0, 80 * 256 / 100);
-const QColor AnalogSignal::SamplingPointColourNe = QColor(0,   0, 0, 80 * 256 / 100);
-const QColor AnalogSignal::SamplingPointColourHi = QColor(0, 200, 0, 80 * 256 / 100);
+const QColor AnalogSignal::SamplingPointColor(0x77, 0x77, 0x77);
+const QColor AnalogSignal::SamplingPointColorLo = QColor(200, 0, 0, 80 * 256 / 100);
+const QColor AnalogSignal::SamplingPointColorNe = QColor(0,   0, 0, 80 * 256 / 100);
+const QColor AnalogSignal::SamplingPointColorHi = QColor(0, 200, 0, 80 * 256 / 100);
 
 const QColor AnalogSignal::ThresholdColor = QColor(0, 0, 0, 30 * 256 / 100);
 const QColor AnalogSignal::ThresholdColorLo = QColor(255, 0, 0, 8 * 256 / 100);
@@ -103,12 +106,12 @@ AnalogSignal::AnalogSignal(
        shared_ptr<data::SignalBase> base) :
        Signal(session, base),
        scale_index_(4), // 20 per div
-       scale_index_drag_offset_(0),
        pos_vdivs_(1),
        neg_vdivs_(1),
        resolution_(0),
        display_type_(DisplayBoth),
-       autoranging_(true)
+       autoranging_(true),
+       value_at_hover_pos_(std::numeric_limits<float>::quiet_NaN())
 {
        axis_pen_ = AxisPen;
 
@@ -118,16 +121,13 @@ AnalogSignal::AnalogSignal(
        connect(analog_data, SIGNAL(min_max_changed(float, float)),
                this, SLOT(on_min_max_changed(float, float)));
 
-       GlobalSettings::register_change_handler(GlobalSettings::Key_View_ConversionThresholdDispMode,
-               bind(&AnalogSignal::on_settingViewConversionThresholdDispMode_changed, this, _1));
-
        GlobalSettings gs;
        conversion_threshold_disp_mode_ =
                gs.value(GlobalSettings::Key_View_ConversionThresholdDispMode).toInt();
 
        div_height_ = gs.value(GlobalSettings::Key_View_DefaultDivHeight).toInt();
 
-       base_->set_colour(SignalColours[base_->index() % countof(SignalColours)]);
+       base_->set_color(SignalColors[base_->index() % countof(SignalColors)]);
        update_scale();
 }
 
@@ -184,26 +184,12 @@ pair<int, int> AnalogSignal::v_extents() const
        return make_pair(-ph, nh);
 }
 
-int AnalogSignal::scale_handle_offset() const
-{
-       const int h = (pos_vdivs_ + neg_vdivs_) * div_height_;
-
-       return ((scale_index_drag_offset_ - scale_index_) * h / 4) - h / 2;
-}
-
-void AnalogSignal::scale_handle_dragged(int offset)
+void AnalogSignal::on_setting_changed(const QString &key, const QVariant &value)
 {
-       const int h = (pos_vdivs_ + neg_vdivs_) * div_height_;
-
-       scale_index_ = scale_index_drag_offset_ - (offset + h / 2) / (h / 4);
-
-       update_scale();
-}
+       Signal::on_setting_changed(key, value);
 
-void AnalogSignal::scale_handle_drag_release()
-{
-       scale_index_drag_offset_ = scale_index_;
-       update_scale();
+       if (key == GlobalSettings::Key_View_ConversionThresholdDispMode)
+               on_settingViewConversionThresholdDispMode_changed(value);
 }
 
 void AnalogSignal::paint_back(QPainter &p, ViewItemPaintParams &pp)
@@ -250,7 +236,7 @@ void AnalogSignal::paint_back(QPainter &p, ViewItemPaintParams &pp)
 
                paint_axis(p, pp, get_visual_y());
        } else {
-               Trace::paint_back(p, pp);
+               Signal::paint_back(p, pp);
                paint_axis(p, pp, get_visual_y());
        }
 }
@@ -269,13 +255,13 @@ void AnalogSignal::paint_mid(QPainter &p, ViewItemPaintParams &pp)
                paint_grid(p, y, pp.left(), pp.right());
 
                shared_ptr<pv::data::AnalogSegment> segment = get_analog_segment_to_paint();
-               if (!segment)
+               if (!segment || (segment->get_sample_count() == 0))
                        return;
 
                const double pixels_offset = pp.pixels_offset();
                const double samplerate = max(1.0, segment->samplerate());
                const pv::util::Timestamp& start_time = segment->start_time();
-               const int64_t last_sample = segment->get_sample_count() - 1;
+               const int64_t last_sample = (int64_t)segment->get_sample_count() - 1;
                const double samples_per_pixel = samplerate * pp.scale();
                const pv::util::Timestamp start = samplerate * (pp.offset() - start_time);
                const pv::util::Timestamp end = start + samples_per_pixel * pp.width();
@@ -286,12 +272,10 @@ void AnalogSignal::paint_mid(QPainter &p, ViewItemPaintParams &pp)
                        (int64_t)0), last_sample);
 
                if (samples_per_pixel < EnvelopeThreshold)
-                       paint_trace(p, segment, y, pp.left(),
-                               start_sample, end_sample,
+                       paint_trace(p, segment, y, pp.left(), start_sample, end_sample,
                                pixels_offset, samples_per_pixel);
                else
-                       paint_envelope(p, segment, y, pp.left(),
-                               start_sample, end_sample,
+                       paint_envelope(p, segment, y, pp.left(), start_sample, end_sample,
                                pixels_offset, samples_per_pixel);
        }
 
@@ -307,10 +291,19 @@ void AnalogSignal::paint_fore(QPainter &p, ViewItemPaintParams &pp)
        if ((display_type_ == DisplayAnalog) || (display_type_ == DisplayBoth)) {
                const int y = get_visual_y();
 
-               // Show the info section on the right side of the trace
-               const QString infotext = QString("%1 V/div").arg(resolution_);
+               QString infotext;
+
+               // Show the info section on the right side of the trace, including
+               // the value at the hover point when the hover marker is enabled
+               // and we have corresponding data available
+               if (show_hover_marker_ && !std::isnan(value_at_hover_pos_)) {
+                       infotext = QString("[%1] %2 V/div")
+                               .arg(format_value_si(value_at_hover_pos_, SIPrefix::unspecified, 0, "V", false))
+                               .arg(resolution_);
+               } else
+                       infotext = QString("%1 V/div").arg(resolution_);
 
-               p.setPen(base_->colour());
+               p.setPen(base_->color());
                p.setFont(QApplication::font());
 
                const QRectF bounding_rect = QRectF(pp.left(),
@@ -320,6 +313,9 @@ void AnalogSignal::paint_fore(QPainter &p, ViewItemPaintParams &pp)
 
                p.drawText(bounding_rect, Qt::AlignRight | Qt::AlignBottom, infotext);
        }
+
+       if (show_hover_marker_)
+               paint_hover_marker(p);
 }
 
 void AnalogSignal::paint_grid(QPainter &p, int y, int left, int right)
@@ -397,9 +393,9 @@ void AnalogSignal::paint_trace(QPainter &p,
                (settings.value(GlobalSettings::Key_View_ShowSamplingPoints).toBool() ||
                paint_thr_dots) && (samples_per_pixel < 0.25);
 
-       p.setPen(base_->colour());
+       p.setPen(base_->color());
 
-       const int64_t points_count = end - start;
+       const int64_t points_count = end - start + 1;
 
        QPointF *points = new QPointF[points_count];
        QPointF *point = points;
@@ -411,20 +407,29 @@ void AnalogSignal::paint_trace(QPainter &p,
        float *sample_block = new float[TracePaintBlockSize];
        segment->get_samples(start, start + sample_count, sample_block);
 
+       if (show_hover_marker_)
+               reset_pixel_values();
+
        const int w = 2;
-       for (int64_t sample = start; sample != end; sample++, block_sample++) {
+       for (int64_t sample = start; sample <= end; sample++, block_sample++) {
 
+               // Fetch next block of samples if we finished the current one
                if (block_sample == TracePaintBlockSize) {
                        block_sample = 0;
                        sample_count = min(points_count - sample, TracePaintBlockSize);
                        segment->get_samples(sample, sample + sample_count, sample_block);
                }
 
-               const float x = (sample / samples_per_pixel -
-                       pixels_offset) + left;
+               const float abs_x = sample / samples_per_pixel - pixels_offset;
+               const float x = left + abs_x;
 
                *point++ = QPointF(x, y - sample_block[block_sample] * scale_);
 
+               // Generate the pixel<->value lookup table for the mouse hover
+               if (show_hover_marker_)
+                       process_next_sample_value(abs_x, sample_block[block_sample]);
+
+               // Create the sampling points if needed
                if (show_sampling_points) {
                        int idx = 0;  // Neutral
 
@@ -439,8 +444,7 @@ void AnalogSignal::paint_trace(QPainter &p,
                                }
                        }
 
-                       sampling_points[idx].push_back(
-                               QRectF(x - (w / 2), y - sample_block[block_sample] * scale_ - (w / 2), w, w));
+                       sampling_points[idx].emplace_back(x - (w / 2), y - sample_block[block_sample] * scale_ - (w / 2), w, w);
                }
        }
        delete[] sample_block;
@@ -449,14 +453,14 @@ void AnalogSignal::paint_trace(QPainter &p,
 
        if (show_sampling_points) {
                if (paint_thr_dots) {
-                       p.setPen(SamplingPointColourNe);
+                       p.setPen(SamplingPointColorNe);
                        p.drawRects(sampling_points[0].data(), sampling_points[0].size());
-                       p.setPen(SamplingPointColourLo);
+                       p.setPen(SamplingPointColorLo);
                        p.drawRects(sampling_points[1].data(), sampling_points[1].size());
-                       p.setPen(SamplingPointColourHi);
+                       p.setPen(SamplingPointColorHi);
                        p.drawRects(sampling_points[2].data(), sampling_points[2].size());
                } else {
-                       p.setPen(SamplingPointColour);
+                       p.setPen(SamplingPointColor);
                        p.drawRects(sampling_points[0].data(), sampling_points[0].size());
                }
        }
@@ -471,6 +475,10 @@ void AnalogSignal::paint_envelope(QPainter &p,
 {
        using pv::data::AnalogSegment;
 
+       // Note: Envelope painting currently doesn't generate a pixel<->value lookup table
+       if (show_hover_marker_)
+               reset_pixel_values();
+
        AnalogSegment::EnvelopeSection e;
        segment->get_envelope_section(e, start, end, samples_per_pixel);
 
@@ -478,7 +486,7 @@ void AnalogSignal::paint_envelope(QPainter &p,
                return;
 
        p.setPen(QPen(Qt::NoPen));
-       p.setBrush(base_->colour());
+       p.setBrush(base_->color());
 
        QRectF *const rects = new QRectF[e.length];
        QRectF *rect = rects;
@@ -486,8 +494,8 @@ void AnalogSignal::paint_envelope(QPainter &p,
        for (uint64_t sample = 0; sample < e.length - 1; sample++) {
                const float x = ((e.scale * sample + e.start) /
                        samples_per_pixel - pixels_offset) + left;
-               const AnalogSegment::EnvelopeSample *const s =
-                       e.samples + sample;
+
+               const AnalogSegment::EnvelopeSample *const s = e.samples + sample;
 
                // We overlap this sample with the next so that vertical
                // gaps do not appear during steep rising or falling edges
@@ -529,9 +537,10 @@ void AnalogSignal::paint_logic_mid(QPainter &p, ViewItemPaintParams &pp)
        const int nh = min(neg_vdivs_, 1) * div_height_;
        const float high_offset = y - ph + signal_margin + 0.5f;
        const float low_offset = y + nh - signal_margin - 0.5f;
+       const float signal_height = low_offset - high_offset;
 
        shared_ptr<pv::data::LogicSegment> segment = get_logic_segment_to_paint();
-       if (!segment)
+       if (!segment || (segment->get_sample_count() == 0))
                return;
 
        double samplerate = segment->samplerate();
@@ -542,7 +551,7 @@ void AnalogSignal::paint_logic_mid(QPainter &p, ViewItemPaintParams &pp)
 
        const double pixels_offset = pp.pixels_offset();
        const pv::util::Timestamp& start_time = segment->start_time();
-       const int64_t last_sample = segment->get_sample_count() - 1;
+       const int64_t last_sample = (int64_t)segment->get_sample_count() - 1;
        const double samples_per_pixel = samplerate * pp.scale();
        const double pixels_per_sample = 1 / samples_per_pixel;
        const pv::util::Timestamp start = samplerate * (pp.offset() - start_time);
@@ -557,6 +566,11 @@ void AnalogSignal::paint_logic_mid(QPainter &p, ViewItemPaintParams &pp)
                samples_per_pixel / LogicSignal::Oversampling, 0);
        assert(edges.size() >= 2);
 
+       const float first_sample_x =
+               pp.left() + (edges.front().first / samples_per_pixel - pixels_offset);
+       const float last_sample_x =
+               pp.left() + (edges.back().first / samples_per_pixel - pixels_offset);
+
        // Check whether we need to paint the sampling points
        GlobalSettings settings;
        const bool show_sampling_points =
@@ -564,25 +578,57 @@ void AnalogSignal::paint_logic_mid(QPainter &p, ViewItemPaintParams &pp)
                (samples_per_pixel < 0.25);
 
        vector<QRectF> sampling_points;
-       float sampling_point_x = 0.0f;
+       float sampling_point_x = first_sample_x;
        int64_t sampling_point_sample = start_sample;
        const int w = 2;
 
-       if (show_sampling_points) {
+       if (show_sampling_points)
                sampling_points.reserve(end_sample - start_sample + 1);
-               sampling_point_x = (edges.cbegin()->first / samples_per_pixel - pixels_offset) + pp.left();
-       }
+
+       // Check whether we need to fill the high areas
+       const bool fill_high_areas =
+               settings.value(GlobalSettings::Key_View_FillSignalHighAreas).toBool();
+       vector<QRectF> high_rects;
+       float rising_edge_x;
+       bool rising_edge_seen = false;
 
        // Paint the edges
        const unsigned int edge_count = edges.size() - 2;
        QLineF *const edge_lines = new QLineF[edge_count];
        line = edge_lines;
 
+       if (edges.front().second) {
+               // Beginning of trace is high
+               rising_edge_x = first_sample_x;
+               rising_edge_seen = true;
+       }
+
        for (auto i = edges.cbegin() + 1; i != edges.cend() - 1; i++) {
-               const float x = ((*i).first / samples_per_pixel -
-                       pixels_offset) + pp.left();
+               // Note: multiple edges occupying a single pixel are represented by an edge
+               // with undefined logic level. This means that only the first falling edge
+               // after a rising edge corresponds to said rising edge - and vice versa. If
+               // more edges with the same logic level follow, they denote multiple edges.
+
+               const float x = pp.left() + ((*i).first / samples_per_pixel - pixels_offset);
                *line++ = QLineF(x, high_offset, x, low_offset);
 
+               if (fill_high_areas) {
+                       // Any edge terminates a high area
+                       if (rising_edge_seen) {
+                               const int width = x - rising_edge_x;
+                               if (width > 0)
+                                       high_rects.emplace_back(rising_edge_x, high_offset,
+                                               width, signal_height);
+                               rising_edge_seen = false;
+                       }
+
+                       // Only rising edges start high areas
+                       if ((*i).second) {
+                               rising_edge_x = x;
+                               rising_edge_seen = true;
+                       }
+               }
+
                if (show_sampling_points)
                        while (sampling_point_sample < (*i).first) {
                                const float y = (*i).second ? low_offset : high_offset;
@@ -604,7 +650,20 @@ void AnalogSignal::paint_logic_mid(QPainter &p, ViewItemPaintParams &pp)
                        sampling_point_x += pixels_per_sample;
                };
 
-       p.setPen(LogicSignal::EdgeColour);
+       if (fill_high_areas) {
+               // Add last high rectangle if the signal is still high at the end of the trace
+               if (rising_edge_seen && (edges.cend() - 1)->second)
+                       high_rects.emplace_back(rising_edge_x, high_offset,
+                               last_sample_x - rising_edge_x, signal_height);
+
+               const QColor fill_color = QColor::fromRgba(settings.value(
+                       GlobalSettings::Key_View_FillSignalHighAreaColor).value<uint32_t>());
+               p.setPen(fill_color);
+               p.setBrush(fill_color);
+               p.drawRects((const QRectF*)(high_rects.data()), high_rects.size());
+       }
+
+       p.setPen(LogicSignal::EdgeColor);
        p.drawLines(edge_lines, edge_count);
        delete[] edge_lines;
 
@@ -612,10 +671,10 @@ void AnalogSignal::paint_logic_mid(QPainter &p, ViewItemPaintParams &pp)
        const unsigned int max_cap_line_count = edges.size();
        QLineF *const cap_lines = new QLineF[max_cap_line_count];
 
-       p.setPen(LogicSignal::HighColour);
+       p.setPen(LogicSignal::HighColor);
        paint_logic_caps(p, cap_lines, edges, true, samples_per_pixel,
                pixels_offset, pp.left(), high_offset);
-       p.setPen(LogicSignal::LowColour);
+       p.setPen(LogicSignal::LowColor);
        paint_logic_caps(p, cap_lines, edges, false, samples_per_pixel,
                pixels_offset, pp.left(), low_offset);
 
@@ -623,7 +682,7 @@ void AnalogSignal::paint_logic_mid(QPainter &p, ViewItemPaintParams &pp)
 
        // Paint the sampling points
        if (show_sampling_points) {
-               p.setPen(SamplingPointColour);
+               p.setPen(SamplingPointColor);
                p.drawRects(sampling_points.data(), sampling_points.size());
        }
 }
@@ -658,11 +717,12 @@ shared_ptr<pv::data::AnalogSegment> AnalogSignal::get_analog_segment_to_paint()
                if (segment_display_mode_ == ShowLastSegmentOnly)
                        segment = segments.back();
 
-               if (segment_display_mode_ == ShowSingleSegmentOnly) {
+               if ((segment_display_mode_ == ShowSingleSegmentOnly) ||
+                               (segment_display_mode_ == ShowLastCompleteSegmentOnly)) {
                        try {
                                segment = segments.at(current_segment_);
-                       } catch (out_of_range) {
-                               qDebug() << "Current analog segment out of range for signal" << base_->name();
+                       } catch (out_of_range&) {
+                               qDebug() << "Current analog segment out of range for signal" << base_->name() << ":" << current_segment_;
                        }
                }
        }
@@ -681,11 +741,12 @@ shared_ptr<pv::data::LogicSegment> AnalogSignal::get_logic_segment_to_paint() co
                if (segment_display_mode_ == ShowLastSegmentOnly)
                        segment = segments.back();
 
-               if (segment_display_mode_ == ShowSingleSegmentOnly) {
+               if ((segment_display_mode_ == ShowSingleSegmentOnly) ||
+                               (segment_display_mode_ == ShowLastCompleteSegmentOnly)) {
                        try {
                                segment = segments.at(current_segment_);
-                       } catch (out_of_range) {
-                               qDebug() << "Current logic segment out of range for signal" << base_->name();
+                       } catch (out_of_range&) {
+                               qDebug() << "Current logic segment out of range for signal" << base_->name() << ":" << current_segment_;
                        }
                }
        }
@@ -727,7 +788,7 @@ void AnalogSignal::update_conversion_widgets()
        conv_threshold_cb_->blockSignals(true);
 
        // Set available options depending on chosen conversion
-       for (pair<QString, int> preset : presets)
+       for (pair<QString, int>& preset : presets)
                conv_threshold_cb_->addItem(preset.first, preset.second);
 
        map < QString, QVariant > options = base_->get_conversion_options();
@@ -754,6 +815,37 @@ void AnalogSignal::update_conversion_widgets()
        conv_threshold_cb_->blockSignals(false);
 }
 
+vector<data::LogicSegment::EdgePair> AnalogSignal::get_nearest_level_changes(uint64_t sample_pos)
+{
+       assert(base_);
+       assert(owner_);
+
+       // Return if there's no logic data or we're showing only the analog trace
+       if (!base_->logic_data() || (display_type_ == DisplayAnalog))
+               return vector<data::LogicSegment::EdgePair>();
+
+       if (sample_pos == 0)
+               return vector<LogicSegment::EdgePair>();
+
+       shared_ptr<LogicSegment> segment = get_logic_segment_to_paint();
+       if (!segment || (segment->get_sample_count() == 0))
+               return vector<LogicSegment::EdgePair>();
+
+       const View *view = owner_->view();
+       assert(view);
+       const double samples_per_pixel = base_->get_samplerate() * view->scale();
+
+       vector<LogicSegment::EdgePair> edges;
+
+       segment->get_surrounding_edges(edges, sample_pos,
+               samples_per_pixel / LogicSignal::Oversampling, 0);
+
+       if (edges.empty())
+               return vector<LogicSegment::EdgePair>();
+
+       return edges;
+}
+
 void AnalogSignal::perform_autoranging(bool keep_divs, bool force_update)
 {
        const deque< shared_ptr<pv::data::AnalogSegment> > &segments =
@@ -765,7 +857,7 @@ void AnalogSignal::perform_autoranging(bool keep_divs, bool force_update)
        static double prev_min = 0, prev_max = 0;
        double min = 0, max = 0;
 
-       for (shared_ptr<pv::data::AnalogSegment> segment : segments) {
+       for (const shared_ptr<pv::data::AnalogSegment>& segment : segments) {
                pair<double, double> mm = segment->get_min_max();
                min = std::min(min, mm.first);
                max = std::max(max, mm.second);
@@ -824,6 +916,64 @@ void AnalogSignal::perform_autoranging(bool keep_divs, bool force_update)
        update_scale();
 }
 
+void AnalogSignal::reset_pixel_values()
+{
+       value_at_pixel_pos_.clear();
+       current_pixel_pos_ = -1;
+       prev_value_at_pixel_ = std::numeric_limits<float>::quiet_NaN();
+}
+
+void AnalogSignal::process_next_sample_value(float x, float value)
+{
+       // Note: NAN is used to indicate the non-existance of a value at this pixel
+
+       if (std::isnan(prev_value_at_pixel_)) {
+               if (x < 0) {
+                       min_value_at_pixel_ = value;
+                       max_value_at_pixel_ = value;
+                       prev_value_at_pixel_ = value;
+                       current_pixel_pos_ = x;
+               } else
+                       prev_value_at_pixel_ = std::numeric_limits<float>::quiet_NaN();
+       }
+
+       const int pixel_pos = (int)(x + 0.5);
+
+       if (pixel_pos > current_pixel_pos_) {
+               if (pixel_pos - current_pixel_pos_ == 1) {
+                       if (std::isnan(prev_value_at_pixel_)) {
+                               value_at_pixel_pos_.push_back(prev_value_at_pixel_);
+                       } else {
+                               // Average the min/max range to create one value for the previous pixel
+                               const float avg = (min_value_at_pixel_ + max_value_at_pixel_) / 2;
+                               value_at_pixel_pos_.push_back(avg);
+                       }
+               } else {
+                       // Interpolate values to create values for the intermediate pixels
+                       const float start_value = prev_value_at_pixel_;
+                       const float end_value = value;
+                       const int steps = fabs(pixel_pos - current_pixel_pos_);
+                       const double gradient = (end_value - start_value) / steps;
+                       for (int i = 0; i < steps; i++) {
+                               if (current_pixel_pos_ + i < 0)
+                                       continue;
+                               value_at_pixel_pos_.push_back(start_value + i * gradient);
+                       }
+               }
+
+               min_value_at_pixel_ = value;
+               max_value_at_pixel_ = value;
+               prev_value_at_pixel_ = value;
+               current_pixel_pos_ = pixel_pos;
+       } else {
+               // Another sample for the same pixel
+               if (value < min_value_at_pixel_)
+                       min_value_at_pixel_ = value;
+               if (value > max_value_at_pixel_)
+                       max_value_at_pixel_ = value;
+       }
+}
+
 void AnalogSignal::populate_popup_form(QWidget *parent, QFormLayout *form)
 {
        // Add the standard options
@@ -911,7 +1061,7 @@ void AnalogSignal::populate_popup_form(QWidget *parent, QFormLayout *form)
 
     connect(conv_threshold_cb_, SIGNAL(currentIndexChanged(int)),
             this, SLOT(on_conv_threshold_changed(int)));
-    connect(conv_threshold_cb_, SIGNAL(editTextChanged(const QString)),
+    connect(conv_threshold_cb_, SIGNAL(editTextChanged(const QString&)),
             this, SLOT(on_conv_threshold_changed()));  // index will be -1
 
        // Add the display type dropdown
@@ -935,6 +1085,24 @@ void AnalogSignal::populate_popup_form(QWidget *parent, QFormLayout *form)
        form->addRow(layout);
 }
 
+void AnalogSignal::hover_point_changed(const QPoint &hp)
+{
+       Signal::hover_point_changed(hp);
+
+       // Note: Even though the view area begins at 0, we exclude 0 because
+       // that's also the value given when the cursor is over the header to the
+       // left of the trace paint area
+       if (hp.x() <= 0) {
+               value_at_hover_pos_ = std::numeric_limits<float>::quiet_NaN();
+       } else {
+               try {
+                       value_at_hover_pos_ = value_at_pixel_pos_.at(hp.x());
+               } catch (out_of_range&) {
+                       value_at_hover_pos_ = std::numeric_limits<float>::quiet_NaN();
+               }
+       }
+}
+
 void AnalogSignal::on_min_max_changed(float min, float max)
 {
        (void)min;