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