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.hpp"
  27 #include "pv/data/analog.hpp"
  28 #include "pv/data/analogsnapshot.hpp"
  29 #include "pv/view/view.hpp"
  30
  31 #include <libsigrok/libsigrok.hpp>
  32
  33 using std::max;
  34 using std::make_pair;
  35 using std::min;
  36 using std::shared_ptr;
  37 using std::deque;
  38
  39 using sigrok::Channel;
  40
  41 namespace pv {
  42 namespace view {
  43
  44 const int AnalogSignal::NominalHeight = 80;
  45
  46 const QColor AnalogSignal::SignalColours[4] = {
  47         QColor(0xC4, 0xA0, 0x00),       // Yellow
  48         QColor(0x87, 0x20, 0x7A),       // Magenta
  49         QColor(0x20, 0x4A, 0x87),       // Blue
  50         QColor(0x4E, 0x9A, 0x06)        // Green
  51 };
  52
  53 const float AnalogSignal::EnvelopeThreshold = 256.0f;
  54
  55 AnalogSignal::AnalogSignal(
  56         pv::Session &session,
  57         shared_ptr<Channel> channel,
  58         shared_ptr<data::Analog> data) :
  59         Signal(session, channel),
  60         data_(data),
  61         scale_(1.0f)
  62 {
  63         colour_ = SignalColours[channel_->index() % countof(SignalColours)];
  64 }
  65
  66 AnalogSignal::~AnalogSignal()
  67 {
  68 }
  69
  70 shared_ptr<pv::data::SignalData> AnalogSignal::data() const
  71 {
  72         return data_;
  73 }
  74
  75 shared_ptr<pv::data::Analog> AnalogSignal::analog_data() const
  76 {
  77         return data_;
  78 }
  79
  80 void AnalogSignal::set_scale(float scale)
  81 {
  82         scale_ = scale;
  83 }
  84
  85 std::pair<int, int> AnalogSignal::v_extents() const
  86 {
  87         return make_pair(-NominalHeight / 2, NominalHeight / 2);
  88 }
  89
  90 void AnalogSignal::paint_back(QPainter &p, const RowItemPaintParams &pp)
  91 {
  92         if (channel_->enabled())
  93                 paint_axis(p, get_visual_y(), pp.left(), pp.right());
  94 }
  95
  96 void AnalogSignal::paint_mid(QPainter &p, const RowItemPaintParams &pp)
  97 {
  98         assert(data_);
  99         assert(owner_);
 100
 101         const int y = get_visual_y();
 102
 103         const View *const view = owner_->view();
 104         assert(view);
 105
 106         const double scale = view->scale();
 107         assert(scale > 0);
 108
 109         const double offset = view->offset();
 110
 111         if (!channel_->enabled())
 112                 return;
 113
 114         const deque< shared_ptr<pv::data::AnalogSnapshot> > &snapshots =
 115                 data_->get_snapshots();
 116         if (snapshots.empty())
 117                 return;
 118
 119         const shared_ptr<pv::data::AnalogSnapshot> &snapshot =
 120                 snapshots.front();
 121
 122         const double pixels_offset = offset / scale;
 123         const double samplerate = data_->samplerate();
 124         const double start_time = data_->get_start_time();
 125         const int64_t last_sample = snapshot->get_sample_count() - 1;
 126         const double samples_per_pixel = samplerate * scale;
 127         const double start = samplerate * (offset - start_time);
 128         const double end = start + samples_per_pixel * pp.width();
 129
 130         const int64_t start_sample = min(max((int64_t)floor(start),
 131                 (int64_t)0), last_sample);
 132         const int64_t end_sample = min(max((int64_t)ceil(end) + 1,
 133                 (int64_t)0), last_sample);
 134
 135         if (samples_per_pixel < EnvelopeThreshold)
 136                 paint_trace(p, snapshot, y, pp.left(),
 137                         start_sample, end_sample,
 138                         pixels_offset, samples_per_pixel);
 139         else
 140                 paint_envelope(p, snapshot, y, pp.left(),
 141                         start_sample, end_sample,
 142                         pixels_offset, samples_per_pixel);
 143 }
 144
 145 void AnalogSignal::paint_trace(QPainter &p,
 146         const shared_ptr<pv::data::AnalogSnapshot> &snapshot,
 147         int y, int left, const int64_t start, const int64_t end,
 148         const double pixels_offset, const double samples_per_pixel)
 149 {
 150         const int64_t sample_count = end - start;
 151
 152         const float *const samples = snapshot->get_samples(start, end);
 153         assert(samples);
 154
 155         p.setPen(colour_);
 156
 157         QPointF *points = new QPointF[sample_count];
 158         QPointF *point = points;
 159
 160         for (int64_t sample = start; sample != end; sample++) {
 161                 const float x = (sample / samples_per_pixel -
 162                         pixels_offset) + left;
 163                 *point++ = QPointF(x,
 164                         y - samples[sample - start] * scale_);
 165         }
 166
 167         p.drawPolyline(points, point - points);
 168
 169         delete[] samples;
 170         delete[] points;
 171 }
 172
 173 void AnalogSignal::paint_envelope(QPainter &p,
 174         const shared_ptr<pv::data::AnalogSnapshot> &snapshot,
 175         int y, int left, const int64_t start, const int64_t end,
 176         const double pixels_offset, const double samples_per_pixel)
 177 {
 178         using pv::data::AnalogSnapshot;
 179
 180         AnalogSnapshot::EnvelopeSection e;
 181         snapshot->get_envelope_section(e, start, end, samples_per_pixel);
 182
 183         if (e.length < 2)
 184                 return;
 185
 186         p.setPen(QPen(Qt::NoPen));
 187         p.setBrush(colour_);
 188
 189         QRectF *const rects = new QRectF[e.length];
 190         QRectF *rect = rects;
 191
 192         for(uint64_t sample = 0; sample < e.length-1; sample++) {
 193                 const float x = ((e.scale * sample + e.start) /
 194                         samples_per_pixel - pixels_offset) + left;
 195                 const AnalogSnapshot::EnvelopeSample *const s =
 196                         e.samples + sample;
 197
 198                 // We overlap this sample with the next so that vertical
 199                 // gaps do not appear during steep rising or falling edges
 200                 const float b = y - max(s->max, (s+1)->min) * scale_;
 201                 const float t = y - min(s->min, (s+1)->max) * scale_;
 202
 203                 float h = b - t;
 204                 if(h >= 0.0f && h <= 1.0f)
 205                         h = 1.0f;
 206                 if(h <= 0.0f && h >= -1.0f)
 207                         h = -1.0f;
 208
 209                 *rect++ = QRectF(x, t, 1.0f, h);
 210         }
 211
 212         p.drawRects(rects, e.length);
 213
 214         delete[] rects;
 215         delete[] e.samples;
 216 }
 217
 218 } // namespace view
 219 } // namespace pv