+ paint_axis(p, y, left, right);
+
+ const deque< shared_ptr<pv::data::AnalogSnapshot> > &snapshots =
+ _data->get_snapshots();
+ if (snapshots.empty())
+ return;
+
+ const shared_ptr<pv::data::AnalogSnapshot> &snapshot =
+ snapshots.front();
+
+ const double pixels_offset = offset / scale;
+ const double samplerate = _data->get_samplerate();
+ const double start_time = _data->get_start_time();
+ const int64_t last_sample = snapshot->get_sample_count() - 1;
+ const double samples_per_pixel = samplerate * scale;
+ const double start = samplerate * (offset - start_time);
+ const double end = start + samples_per_pixel * (right - left);
+
+ const int64_t start_sample = min(max((int64_t)floor(start),
+ (int64_t)0), last_sample);
+ const int64_t end_sample = min(max((int64_t)ceil(end),
+ (int64_t)0), last_sample);
+
+ const float* samples = snapshot->get_samples();
+ assert(samples);
+
+ QPointF *points = new QPointF[end_sample - start_sample];
+ QPointF *point = points;
+
+ for (int64_t sample = start_sample;
+ sample != end_sample; sample++) {
+ const float x = (sample / samples_per_pixel -
+ pixels_offset) + left;
+ *point++ = QPointF(x, samples[sample] + y);
+ }
+
+ p.drawPoints(points, point - points);
+
+ delete[] points;