git.sesse.net Git - kdenlive/blob - src/onmonitoritems/onmonitorcornersitem.cpp

   1 /***************************************************************************
   2  *   Copyright (C) 2010 by Till Theato (root@ttill.de)                     *
   3  *                                                                         *
   4  *   This program is free software; you can redistribute it and/or modify  *
   5  *   it under the terms of the GNU General Public License as published by  *
   6  *   the Free Software Foundation; either version 2 of the License, or     *
   7  *   (at your option) any later version.                                   *
   8  *                                                                         *
   9  *   This program is distributed in the hope that it will be useful,       *
  10  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  11  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  12  *   GNU General Public License for more details.                          *
  13  *                                                                         *
  14  *   You should have received a copy of the GNU General Public License     *
  15  *   along with this program; if not, write to the                         *
  16  *   Free Software Foundation, Inc.,                                       *
  17  *   51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA          *
  18  ***************************************************************************/
  19
  20 #include "onmonitorcornersitem.h"
  21 #include "kdenlivesettings.h"
  22
  23 #include <algorithm>
  24
  25 #include <QGraphicsSceneMouseEvent>
  26 #include <QPainter>
  27 #include <QStyleOptionGraphicsItem>
  28 #include <QCursor>
  29
  30 OnMonitorCornersItem::OnMonitorCornersItem(MonitorScene* scene, QGraphicsItem* parent) :
  31         AbstractOnMonitorItem(scene),
  32         QGraphicsPolygonItem(parent)
  33 {
  34     setFlags(QGraphicsItem::ItemIsMovable | QGraphicsItem::ItemIsSelectable);
  35
  36     QPen framepen(Qt::SolidLine);
  37     framepen.setColor(Qt::yellow);
  38     setPen(framepen);
  39     setBrush(Qt::NoBrush);
  40 }
  41
  42 OnMonitorCornersItem::cornersActions OnMonitorCornersItem::getMode(QPointF pos)
  43 {
  44     QPainterPath mouseArea;
  45     pos = mapFromScene(pos);
  46     mouseArea.addRect(pos.x() - 6, pos.y() - 6, 12, 12);
  47     if (mouseArea.contains(polygon().at(0)))
  48         return Corner1;
  49     else if (mouseArea.contains(polygon().at(1)))
  50         return Corner2;
  51     else if (mouseArea.contains(polygon().at(2)))
  52         return Corner3;
  53     else if (mouseArea.contains(polygon().at(3)))
  54         return Corner4;
  55     else if (KdenliveSettings::onmonitoreffects_cornersshowcontrols() && mouseArea.contains(getCentroid()))
  56         return Move;
  57     else
  58         return NoAction;
  59 }
  60
  61 void OnMonitorCornersItem::slotMousePressed(QGraphicsSceneMouseEvent* event)
  62 {
  63     event->accept();
  64
  65     if (!isEnabled())
  66         return;
  67
  68     m_mode = getMode(event->scenePos());
  69     m_lastPoint = event->scenePos();
  70 }
  71
  72 void OnMonitorCornersItem::slotMouseMoved(QGraphicsSceneMouseEvent* event)
  73 {
  74     event->accept();
  75
  76     if (!isEnabled()) {
  77         emit requestCursor(QCursor(Qt::ArrowCursor));
  78         return;
  79     }
  80
  81     /*if (event->buttons() != Qt::NoButton && (event->screenPos() - m_screenClickPoint).manhattanLength() < QApplication::startDragDistance()) {
  82      *   event->accept();
  83      *   return;
  84     }*/
  85
  86     if (event->buttons() & Qt::LeftButton) {
  87         QPointF mousePos = mapFromScene(event->scenePos());
  88         QPolygonF p = polygon();
  89         switch (m_mode) {
  90         case Corner1:
  91             p.replace(0, mousePos);
  92             m_modified = true;
  93             break;
  94         case Corner2:
  95             p.replace(1, mousePos);
  96             m_modified = true;
  97             break;
  98         case Corner3:
  99             p.replace(2, mousePos);
 100             m_modified = true;
 101             break;
 102         case Corner4:
 103             p.replace(3, mousePos);
 104             m_modified = true;
 105             break;
 106         case Move:
 107             p.translate(mousePos - m_lastPoint);
 108             m_modified = true;
 109             break;
 110         default:
 111             break;
 112         }
 113         m_lastPoint = mousePos;
 114         setPolygon(p);
 115     } else {
 116         switch (getMode(event->scenePos())) {
 117         case NoAction:
 118             emit requestCursor(QCursor(Qt::ArrowCursor));
 119             break;
 120         case Move:
 121             emit requestCursor(QCursor(Qt::SizeAllCursor));
 122             break;
 123         default:
 124             emit requestCursor(QCursor(Qt::OpenHandCursor));
 125             break;
 126         }
 127     }
 128     if (m_modified && KdenliveSettings::monitorscene_directupdate()) {
 129         emit actionFinished();
 130         m_modified = false;
 131     }
 132 }
 133
 134 void OnMonitorCornersItem::paint(QPainter* painter, const QStyleOptionGraphicsItem* option, QWidget* widget)
 135 {
 136     painter->setPen(QPen(Qt::yellow, 1, Qt::SolidLine));
 137
 138     if (KdenliveSettings::onmonitoreffects_cornersshowlines())
 139         QGraphicsPolygonItem::paint(painter, option, widget);
 140
 141     painter->setRenderHint(QPainter::Antialiasing);
 142     painter->setBrush(QBrush(Qt::yellow));
 143     double handleSize = 4 / painter->matrix().m11();
 144     painter->drawEllipse(polygon().at(0), handleSize, handleSize);
 145     painter->drawEllipse(polygon().at(1), handleSize, handleSize);
 146     painter->drawEllipse(polygon().at(2), handleSize, handleSize);
 147     painter->drawEllipse(polygon().at(3), handleSize, handleSize);
 148
 149     if (KdenliveSettings::onmonitoreffects_cornersshowcontrols()) {
 150         painter->setPen(QPen(Qt::red, 2, Qt::SolidLine));
 151         QPointF c = getCentroid();
 152         handleSize *= 1.5;
 153         painter->drawLine(QLineF(c - QPointF(handleSize, handleSize), c + QPointF(handleSize, handleSize)));
 154         painter->drawLine(QLineF(c - QPointF(-handleSize, handleSize), c + QPointF(-handleSize, handleSize)));
 155     }
 156 }
 157
 158 QPointF OnMonitorCornersItem::getCentroid()
 159 {
 160     QList <QPointF> p = sortedClockwise();
 161
 162     /*
 163      * See: http://local.wasp.uwa.edu.au/~pbourke/geometry/polyarea/
 164      */
 165
 166     double A = 0;
 167     int i, j;
 168     for (i = 0; i < 4; ++i) {
 169         j = (i + 1) % 4;
 170         A += p[j].x() * p[i].y() - p[i].x() * p[j].y();
 171     }
 172     A /= 2.;
 173     A = qAbs(A);
 174
 175     double x = 0, y = 0, f;
 176     for (i = 0; i < 4; ++i) {
 177         j = (i + 1) % 4;
 178         f = (p[i].x() * p[j].y() - p[j].x() * p[i].y());
 179         x += f * (p[i].x() + p[j].x());
 180         y += f * (p[i].y() + p[j].y());
 181     }
 182     x /= 6*A;
 183     y /= 6*A;
 184     return QPointF(x, y);
 185 }
 186
 187 QList <QPointF> OnMonitorCornersItem::sortedClockwise()
 188 {
 189     QList <QPointF> points = polygon().toList();
 190     QPointF& a = points[0];
 191     QPointF& b = points[1];
 192     QPointF& c = points[2];
 193     QPointF& d = points[3];
 194
 195     /*
 196      * http://stackoverflow.com/questions/242404/sort-four-points-in-clockwise-order
 197      */
 198
 199     double abc = a.x() * b.y() - a.y() * b.x() + b.x() * c.y() - b.y() * c.x() + c.x() * a.y() - c.y() * a.x();
 200     if (abc > 0) {
 201         double acd = a.x() * c.y() - a.y() * c.x() + c.x() * d.y() - c.y() * d.x() + d.x() * a.y() - d.y() * a.x();
 202         if (acd > 0) {
 203             ;
 204         } else {
 205             double abd = a.x() * b.y() - a.y() * b.x() + b.x() * d.y() - b.y() * d.x() + d.x() * a.y() - d.y() * a.x();
 206             if (abd > 0) {
 207                 std::swap(d, c);
 208             } else{
 209                 std::swap(a, d);
 210             }
 211         }
 212     } else {
 213         double acd = a.x() * c.y() - a.y() * c.x() + c.x() * d.y() - c.y() * d.x() + d.x() * a.y() - d.y() * a.x();
 214         if (acd > 0) {
 215             double abd = a.x() * b.y() - a.y() * b.x() + b.x() * d.y() - b.y() * d.x() + d.x() * a.y() - d.y() * a.x();
 216             if (abd > 0) {
 217                 std::swap(b, c);
 218             } else {
 219                 std::swap(a, b);
 220             }
 221         } else {
 222             std::swap(a, c);
 223         }
 224     }
 225     return points;
 226 }
 227
 228 #include "onmonitorcornersitem.moc"