pv/view/viewport.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 <cassert>
  22 #include <cmath>
  23 #include <algorithm>
  24
  25 #include "signal.hpp"
  26 #include "view.hpp"
  27 #include "viewport.hpp"
  28
  29 #include <pv/sigsession.hpp>
  30
  31 #include <QMouseEvent>
  32
  33 using std::abs;
  34 using std::max;
  35 using std::min;
  36 using std::shared_ptr;
  37 using std::stable_sort;
  38 using std::vector;
  39
  40 namespace pv {
  41 namespace view {
  42
  43 Viewport::Viewport(View &parent) :
  44         QWidget(&parent),
  45         view_(parent),
  46         mouse_down_valid_(false),
  47         pinch_zoom_active_(false)
  48 {
  49         setAttribute(Qt::WA_AcceptTouchEvents, true);
  50
  51         setMouseTracking(true);
  52         setAutoFillBackground(true);
  53         setBackgroundRole(QPalette::Base);
  54
  55         connect(&view_, SIGNAL(signals_moved()),
  56                 this, SLOT(on_signals_moved()));
  57 }
  58
  59 void Viewport::paintEvent(QPaintEvent*)
  60 {
  61         vector< shared_ptr<RowItem> > row_items(view_.begin(), view_.end());
  62         stable_sort(row_items.begin(), row_items.end(),
  63                 [](const shared_ptr<RowItem> &a, const shared_ptr<RowItem> &b) {
  64                         return a->visual_v_offset() < b->visual_v_offset(); });
  65
  66         QPainter p(this);
  67         p.setRenderHint(QPainter::Antialiasing);
  68
  69         if (view_.cursors_shown())
  70                 view_.cursors().draw_viewport_background(p, rect());
  71
  72         // Plot the signal
  73         for (const shared_ptr<RowItem> r : row_items)
  74         {
  75                 assert(r);
  76                 r->paint_back(p, 0, width());
  77         }
  78
  79         for (const shared_ptr<RowItem> r : row_items)
  80                 r->paint_mid(p, 0, width());
  81
  82         for (const shared_ptr<RowItem> r : row_items)
  83                 r->paint_fore(p, 0, width());
  84
  85         if (view_.cursors_shown())
  86                 view_.cursors().draw_viewport_foreground(p, rect());
  87
  88         p.end();
  89 }
  90
  91 bool Viewport::event(QEvent *event)
  92 {
  93         switch (event->type()) {
  94         case QEvent::TouchBegin:
  95         case QEvent::TouchUpdate:
  96         case QEvent::TouchEnd:
  97                 if (touchEvent(static_cast<QTouchEvent *>(event)))
  98                         return true;
  99                 break;
 100
 101         default:
 102                 break;
 103         }
 104
 105         return QWidget::event(event);
 106 }
 107
 108 void Viewport::mousePressEvent(QMouseEvent *event)
 109 {
 110         assert(event);
 111
 112         if (event->button() == Qt::LeftButton) {
 113                 mouse_down_point_ = event->pos();
 114                 mouse_down_offset_ = view_.offset();
 115                 mouse_down_valid_ = true;
 116         }
 117 }
 118
 119 void Viewport::mouseReleaseEvent(QMouseEvent *event)
 120 {
 121         assert(event);
 122
 123         if (event->button() == Qt::LeftButton)
 124                 mouse_down_valid_ = false;
 125 }
 126
 127 void Viewport::mouseMoveEvent(QMouseEvent *event)
 128 {
 129         assert(event);
 130
 131         if (event->buttons() & Qt::LeftButton) {
 132                 if (!mouse_down_valid_) {
 133                         mouse_down_point_ = event->pos();
 134                         mouse_down_offset_ = view_.offset();
 135                         mouse_down_valid_ = true;
 136                 }
 137
 138                 view_.set_scale_offset(view_.scale(),
 139                         mouse_down_offset_ +
 140                         (mouse_down_point_ - event->pos()).x() *
 141                         view_.scale());
 142         }
 143 }
 144
 145 void Viewport::mouseDoubleClickEvent(QMouseEvent *event)
 146 {
 147         assert(event);
 148
 149         if (event->buttons() & Qt::LeftButton)
 150                 view_.zoom(2.0, event->x());
 151         else if (event->buttons() & Qt::RightButton)
 152                 view_.zoom(-2.0, event->x());
 153 }
 154
 155 void Viewport::wheelEvent(QWheelEvent *event)
 156 {
 157         assert(event);
 158
 159         if (event->orientation() == Qt::Vertical) {
 160                 // Vertical scrolling is interpreted as zooming in/out
 161                 view_.zoom(event->delta() / 120, event->x());
 162         } else if (event->orientation() == Qt::Horizontal) {
 163                 // Horizontal scrolling is interpreted as moving left/right
 164                 view_.set_scale_offset(view_.scale(),
 165                                        event->delta() * view_.scale()
 166                                        + view_.offset());
 167         }
 168 }
 169
 170 bool Viewport::touchEvent(QTouchEvent *event)
 171 {
 172         QList<QTouchEvent::TouchPoint> touchPoints = event->touchPoints();
 173
 174         if (touchPoints.count() != 2) {
 175                 pinch_zoom_active_ = false;
 176                 return false;
 177         }
 178
 179         const QTouchEvent::TouchPoint &touchPoint0 = touchPoints.first();
 180         const QTouchEvent::TouchPoint &touchPoint1 = touchPoints.last();
 181
 182         if (!pinch_zoom_active_ ||
 183             (event->touchPointStates() & Qt::TouchPointPressed)) {
 184                 pinch_offset0_ = view_.offset() + view_.scale() * touchPoint0.pos().x();
 185                 pinch_offset1_ = view_.offset() + view_.scale() * touchPoint1.pos().x();
 186                 pinch_zoom_active_ = true;
 187         }
 188
 189         double w = touchPoint1.pos().x() - touchPoint0.pos().x();
 190         if (abs(w) >= 1.0) {
 191                 double scale = (pinch_offset1_ - pinch_offset0_) / w;
 192                 if (scale < 0)
 193                         scale = -scale;
 194                 double offset = pinch_offset0_ - touchPoint0.pos().x() * scale;
 195                 if (scale > 0)
 196                         view_.set_scale_offset(scale, offset);
 197         }
 198
 199         if (event->touchPointStates() & Qt::TouchPointReleased) {
 200                 pinch_zoom_active_ = false;
 201
 202                 if (touchPoint0.state() & Qt::TouchPointReleased) {
 203                         // Primary touch released
 204                         mouse_down_valid_ = false;
 205                 } else {
 206                         // Update the mouse down fields so that continued
 207                         // dragging with the primary touch will work correctly
 208                         mouse_down_point_ = touchPoint0.pos().toPoint();
 209                         mouse_down_offset_ = view_.offset();
 210                         mouse_down_valid_ = true;
 211                 }
 212         }
 213
 214         return true;
 215 }
 216
 217 void Viewport::on_signals_moved()
 218 {
 219         update();
 220 }
 221
 222 } // namespace view
 223 } // namespace pv