pv/view/analogsignal.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 #include <extdef.h>
  22
  23 #include <cassert>
  24 #include <cmath>
  25
  26 #include "analogsignal.h"
  27 #include "pv/data/analog.h"
  28 #include "pv/data/analogsnapshot.h"
  29 #include "pv/view/view.h"
  30
  31 #include <libsigrok/libsigrok.hpp>
  32
  33 using std::max;
  34 using std::min;
  35 using std::shared_ptr;
  36 using std::deque;
  37
  38 using sigrok::Channel;
  39
  40 namespace pv {
  41 namespace view {
  42
  43 const QColor AnalogSignal::SignalColours[4] = {
  44         QColor(0xC4, 0xA0, 0x00),       // Yellow
  45         QColor(0x87, 0x20, 0x7A),       // Magenta
  46         QColor(0x20, 0x4A, 0x87),       // Blue
  47         QColor(0x4E, 0x9A, 0x06)        // Green
  48 };
  49
  50 const float AnalogSignal::EnvelopeThreshold = 256.0f;
  51
  52 AnalogSignal::AnalogSignal(
  53         pv::SigSession &session,
  54         shared_ptr<Channel> channel,
  55         shared_ptr<data::Analog> data) :
  56         Signal(session, channel),
  57         _data(data),
  58         _scale(1.0f)
  59 {
  60         _colour = SignalColours[_channel->index() % countof(SignalColours)];
  61 }
  62
  63 AnalogSignal::~AnalogSignal()
  64 {
  65 }
  66
  67 shared_ptr<pv::data::SignalData> AnalogSignal::data() const
  68 {
  69         return _data;
  70 }
  71
  72 shared_ptr<pv::data::Analog> AnalogSignal::analog_data() const
  73 {
  74         return _data;
  75 }
  76
  77 void AnalogSignal::set_scale(float scale)
  78 {
  79         _scale = scale;
  80 }
  81
  82 void AnalogSignal::paint_back(QPainter &p, int left, int right)
  83 {
  84         if (_channel->enabled())
  85                 paint_axis(p, get_y(), left, right);
  86 }
  87
  88 void AnalogSignal::paint_mid(QPainter &p, int left, int right)
  89 {
  90         assert(_data);
  91         assert(right >= left);
  92
  93         assert(_view);
  94         const int y = _v_offset - _view->v_offset();
  95
  96         const double scale = _view->scale();
  97         assert(scale > 0);
  98
  99         const double offset = _view->offset();
 100
 101         if (!_channel->enabled())
 102                 return;
 103
 104         const deque< shared_ptr<pv::data::AnalogSnapshot> > &snapshots =
 105                 _data->get_snapshots();
 106         if (snapshots.empty())
 107                 return;
 108
 109         const shared_ptr<pv::data::AnalogSnapshot> &snapshot =
 110                 snapshots.front();
 111
 112         const double pixels_offset = offset / scale;
 113         const double samplerate = _data->samplerate();
 114         const double start_time = _data->get_start_time();
 115         const int64_t last_sample = snapshot->get_sample_count() - 1;
 116         const double samples_per_pixel = samplerate * scale;
 117         const double start = samplerate * (offset - start_time);
 118         const double end = start + samples_per_pixel * (right - left);
 119
 120         const int64_t start_sample = min(max((int64_t)floor(start),
 121                 (int64_t)0), last_sample);
 122         const int64_t end_sample = min(max((int64_t)ceil(end) + 1,
 123                 (int64_t)0), last_sample);
 124
 125         if (samples_per_pixel < EnvelopeThreshold)
 126                 paint_trace(p, snapshot, y, left,
 127                         start_sample, end_sample,
 128                         pixels_offset, samples_per_pixel);
 129         else
 130                 paint_envelope(p, snapshot, y, left,
 131                         start_sample, end_sample,
 132                         pixels_offset, samples_per_pixel);
 133 }
 134
 135 void AnalogSignal::paint_trace(QPainter &p,
 136         const shared_ptr<pv::data::AnalogSnapshot> &snapshot,
 137         int y, int left, const int64_t start, const int64_t end,
 138         const double pixels_offset, const double samples_per_pixel)
 139 {
 140         const int64_t sample_count = end - start;
 141
 142         const float *const samples = snapshot->get_samples(start, end);
 143         assert(samples);
 144
 145         p.setPen(_colour);
 146
 147         QPointF *points = new QPointF[sample_count];
 148         QPointF *point = points;
 149
 150         for (int64_t sample = start; sample != end; sample++) {
 151                 const float x = (sample / samples_per_pixel -
 152                         pixels_offset) + left;
 153                 *point++ = QPointF(x,
 154                         y - samples[sample - start] * _scale);
 155         }
 156
 157         p.drawPolyline(points, point - points);
 158
 159         delete[] samples;
 160         delete[] points;
 161 }
 162
 163 void AnalogSignal::paint_envelope(QPainter &p,
 164         const shared_ptr<pv::data::AnalogSnapshot> &snapshot,
 165         int y, int left, const int64_t start, const int64_t end,
 166         const double pixels_offset, const double samples_per_pixel)
 167 {
 168         using pv::data::AnalogSnapshot;
 169
 170         AnalogSnapshot::EnvelopeSection e;
 171         snapshot->get_envelope_section(e, start, end, samples_per_pixel);
 172
 173         if (e.length < 2)
 174                 return;
 175
 176         p.setPen(QPen(Qt::NoPen));
 177         p.setBrush(_colour);
 178
 179         QRectF *const rects = new QRectF[e.length];
 180         QRectF *rect = rects;
 181
 182         for(uint64_t sample = 0; sample < e.length-1; sample++) {
 183                 const float x = ((e.scale * sample + e.start) /
 184                         samples_per_pixel - pixels_offset) + left;
 185                 const AnalogSnapshot::EnvelopeSample *const s =
 186                         e.samples + sample;
 187
 188                 // We overlap this sample with the next so that vertical
 189                 // gaps do not appear during steep rising or falling edges
 190                 const float b = y - max(s->max, (s+1)->min) * _scale;
 191                 const float t = y - min(s->min, (s+1)->max) * _scale;
 192
 193                 float h = b - t;
 194                 if(h >= 0.0f && h <= 1.0f)
 195                         h = 1.0f;
 196                 if(h <= 0.0f && h >= -1.0f)
 197                         h = -1.0f;
 198
 199                 *rect++ = QRectF(x, t, 1.0f, h);
 200         }
 201
 202         p.drawRects(rects, e.length);
 203
 204         delete[] rects;
 205         delete[] e.samples;
 206 }
 207
 208 } // namespace view
 209 } // namespace pv