sigview.cpp

   1 /*
   2  * This file is part of the sigrok 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 "sigview.h"
  22
  23 #include "sigsession.h"
  24 #include "signal.h"
  25
  26 #include "extdef.h"
  27
  28 #include <QMouseEvent>
  29 #include <QTextStream>
  30
  31 #include <math.h>
  32
  33 #include <boost/foreach.hpp>
  34
  35 using namespace boost;
  36 using namespace std;
  37
  38 const double SigView::MaxScale = 1e9;
  39 const double SigView::MinScale = 1e-15;
  40
  41 const int SigView::SignalHeight = 50;
  42 const int SigView::LabelMarginWidth = 70;
  43 const int SigView::RulerHeight = 30;
  44
  45 const int SigView::MinorTickSubdivision = 4;
  46 const int SigView::ScaleUnits[3] = {1, 2, 5};
  47
  48 const QString SigView::SIPrefixes[9] =
  49         {"f", "p", "n", QChar(0x03BC), "m", "", "k", "M", "G"};
  50 const int SigView::FirstSIPrefixPower = -15;
  51
  52 SigView::SigView(SigSession &session, QWidget *parent) :
  53         QGLWidget(parent),
  54         _session(session),
  55         _scale(1e-6),
  56         _offset(0)
  57 {
  58         connect(&_session, SIGNAL(data_updated()),
  59                 this, SLOT(data_updated()));
  60
  61         setMouseTracking(true);
  62         setAutoFillBackground(false);
  63 }
  64
  65 void SigView::initializeGL()
  66 {
  67 }
  68
  69 void SigView::resizeGL(int width, int height)
  70 {
  71         setup_viewport(width, height);
  72 }
  73
  74 void SigView::paintEvent(QPaintEvent *event)
  75 {
  76         int offset;
  77
  78         const vector< shared_ptr<Signal> > &sigs =
  79                 _session.get_signals();
  80
  81         // Prepare for OpenGL rendering
  82         makeCurrent();
  83         glMatrixMode(GL_MODELVIEW);
  84         glPushMatrix();
  85
  86         setup_viewport(width(), height());
  87
  88         qglClearColor(Qt::white);
  89         glClear(GL_COLOR_BUFFER_BIT);
  90
  91         // Plot the signal
  92         glEnable(GL_SCISSOR_TEST);
  93         glScissor(LabelMarginWidth, 0, width(), height());
  94         offset = RulerHeight;
  95         BOOST_FOREACH(const shared_ptr<Signal> s, sigs)
  96         {
  97                 assert(s);
  98
  99                 const QRect signal_rect(LabelMarginWidth, offset,
 100                         width() - LabelMarginWidth, SignalHeight);
 101
 102                 s->paint(*this, signal_rect, _scale, _offset);
 103
 104                 offset += SignalHeight;
 105         }
 106
 107         glDisable(GL_SCISSOR_TEST);
 108
 109         // Prepare for QPainter rendering
 110         glMatrixMode(GL_MODELVIEW);
 111         glPopMatrix();
 112
 113         QPainter painter(this);
 114         painter.setRenderHint(QPainter::Antialiasing);
 115
 116         // Paint the labels
 117         offset = RulerHeight;
 118         BOOST_FOREACH(const shared_ptr<Signal> s, sigs)
 119         {
 120                 assert(s);
 121
 122                 const QRect label_rect(0, offset,
 123                         LabelMarginWidth, SignalHeight);
 124                 s->paint_label(painter, label_rect);
 125
 126                 offset += SignalHeight;
 127         }
 128
 129         // Paint the ruler
 130         paint_ruler(painter);
 131
 132         painter.end();
 133 }
 134
 135 void SigView::data_updated()
 136 {
 137         update();
 138 }
 139
 140 void SigView::mousePressEvent(QMouseEvent *event)
 141 {
 142         assert(event);
 143
 144         _mouse_down_point = event->pos();
 145         _mouse_down_offset = _offset;
 146 }
 147
 148 void SigView::mouseMoveEvent(QMouseEvent *event)
 149 {
 150         assert(event);
 151
 152         if(event->buttons() & Qt::LeftButton)
 153         {
 154                 _offset = _mouse_down_offset + (_mouse_down_point - event->pos()).x() * _scale;
 155                 update();
 156         }
 157 }
 158
 159 void SigView::mouseReleaseEvent(QMouseEvent *event)
 160 {
 161         assert(event);
 162 }
 163
 164 void SigView::wheelEvent(QWheelEvent *event)
 165 {
 166         assert(event);
 167
 168         const double x = event->x() - LabelMarginWidth;
 169         const double cursor_offset = _offset + _scale * x;
 170         _scale *= powf(3.0/2.0, -event->delta() / 120);
 171         _scale = max(min(_scale, MaxScale), MinScale);
 172         _offset = cursor_offset - _scale * x;
 173         update();
 174 }
 175
 176 void SigView::setup_viewport(int width, int height)
 177 {
 178         glViewport(0, 0, (GLint)width, (GLint)height);
 179         glMatrixMode(GL_PROJECTION);
 180         glLoadIdentity();
 181         glOrtho(0, width, height, 0, -1, 1);
 182         glMatrixMode(GL_MODELVIEW);
 183 }
 184
 185 void SigView::paint_ruler(QPainter &p)
 186 {
 187         const double MinSpacing = 80;
 188
 189         const double min_period = _scale * MinSpacing;
 190
 191         const int order = (int)floorf(log10f(min_period));
 192         const double order_decimal = pow(10, order);
 193
 194         int unit = 0;
 195         double tick_period = 0.0f;
 196
 197         do
 198         {
 199                 tick_period = order_decimal * ScaleUnits[unit++];
 200         } while(tick_period < min_period && unit < countof(ScaleUnits));
 201
 202         const int prefix = (order - FirstSIPrefixPower) / 3;
 203         assert(prefix >= 0);
 204         assert(prefix < countof(SIPrefixes));
 205
 206         const int text_height = p.boundingRect(0, 0, INT_MAX, INT_MAX,
 207                 Qt::AlignLeft | Qt::AlignTop, "8").height();
 208
 209         // Draw the tick marks
 210         p.setPen(Qt::black);
 211
 212         const double minor_tick_period = tick_period / MinorTickSubdivision;
 213         const double first_major_division = floor(_offset / tick_period);
 214         const double first_minor_division = ceil(_offset / minor_tick_period);
 215         const double t0 = first_major_division * tick_period;
 216
 217         int division = (int)round(first_minor_division -
 218                 first_major_division * MinorTickSubdivision);
 219         while(1)
 220         {
 221                 const double t = t0 + division * minor_tick_period;
 222                 const double x = (t - _offset) / _scale + LabelMarginWidth;
 223
 224                 if(x >= width())
 225                         break;
 226
 227                 if(division % MinorTickSubdivision == 0)
 228                 {
 229                         // Draw a major tick
 230                         QString s;
 231                         QTextStream ts(&s);
 232                         ts << (t / order_decimal) << SIPrefixes[prefix] << "s";
 233                         p.drawText(x, 0, 0, text_height, Qt::AlignCenter | Qt::AlignTop |
 234                                 Qt::TextDontClip, s);
 235                         p.drawLine(x, text_height, x, RulerHeight);
 236                 }
 237                 else
 238                 {
 239                         // Draw a minor tick
 240                         p.drawLine(x, (text_height + RulerHeight) / 2, x, RulerHeight);
 241                 }
 242
 243                 division++;
 244         }
 245 }