+ scale_index_drag_offset_ = scale_index_;
+}
+
+void AnalogSignal::paint_back(QPainter &p, const ViewItemPaintParams &pp)
+{
+ if (channel_->enabled()) {
+ Trace::paint_back(p, pp);
+ paint_axis(p, pp, get_visual_y());
+ }
+}
+
+void AnalogSignal::paint_mid(QPainter &p, const ViewItemPaintParams &pp)
+{
+ assert(data_);
+ assert(owner_);
+
+ const int y = get_visual_y();
+
+ if (!channel_->enabled())
+ return;
+
+ const deque< shared_ptr<pv::data::AnalogSegment> > &segments =
+ data_->analog_segments();
+ if (segments.empty())
+ return;
+
+ const shared_ptr<pv::data::AnalogSegment> &segment =
+ segments.front();
+
+ 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 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();
+
+ const int64_t start_sample = min(max(floor(start).convert_to<int64_t>(),
+ (int64_t)0), last_sample);
+ const int64_t end_sample = min(max((ceil(end) + 1).convert_to<int64_t>(),
+ (int64_t)0), last_sample);
+
+ if (samples_per_pixel < EnvelopeThreshold)
+ 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,
+ pixels_offset, samples_per_pixel);
+}
+
+void AnalogSignal::paint_trace(QPainter &p,
+ const shared_ptr<pv::data::AnalogSegment> &segment,
+ int y, int left, const int64_t start, const int64_t end,
+ const double pixels_offset, const double samples_per_pixel)
+{
+ const float scale = this->scale();
+ const int64_t sample_count = end - start;
+
+ const float *const samples = segment->get_samples(start, end);
+ assert(samples);
+
+ p.setPen(colour_);
+
+ QPointF *points = new QPointF[sample_count];
+ QPointF *point = points;
+
+ for (int64_t sample = start; sample != end; sample++) {
+ const float x = (sample / samples_per_pixel -
+ pixels_offset) + left;
+ *point++ = QPointF(x,
+ y - samples[sample - start] * scale);
+ }
+
+ p.drawPolyline(points, point - points);
+
+ delete[] samples;
+ delete[] points;
+}
+
+void AnalogSignal::paint_envelope(QPainter &p,
+ const shared_ptr<pv::data::AnalogSegment> &segment,
+ int y, int left, const int64_t start, const int64_t end,
+ const double pixels_offset, const double samples_per_pixel)
+{
+ using pv::data::AnalogSegment;
+
+ const float scale = this->scale();
+
+ AnalogSegment::EnvelopeSection e;
+ segment->get_envelope_section(e, start, end, samples_per_pixel);
+
+ if (e.length < 2)
+ return;
+
+ p.setPen(QPen(Qt::NoPen));
+ p.setBrush(colour_);
+
+ QRectF *const rects = new QRectF[e.length];
+ QRectF *rect = rects;
+
+ 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;
+
+ // We overlap this sample with the next so that vertical
+ // gaps do not appear during steep rising or falling edges
+ const float b = y - max(s->max, (s+1)->min) * scale;
+ const float t = y - min(s->min, (s+1)->max) * scale;
+
+ float h = b - t;
+ if (h >= 0.0f && h <= 1.0f)
+ h = 1.0f;
+ if (h <= 0.0f && h >= -1.0f)
+ h = -1.0f;
+
+ *rect++ = QRectF(x, t, 1.0f, h);
+ }
+
+ p.drawRects(rects, e.length);
+
+ delete[] rects;
+ delete[] e.samples;