File indexing completed on 2025-01-12 12:39:33

 /************************************************************************
  *                                  *
  *  This file is part of Kooka, a scanning/OCR application using    *
  *  Qt <http://www.qt.io> and KDE Frameworks <http://www.kde.org>.  *
  *                                  *
  *  Copyright (C) 2000-2016 Klaas Freitag <freitag@suse.de>     *
  *                          Jonathan Marten <jjm@keelhaul.me.uk>    *
  *                                  *
  *  Kooka is free software; you can redistribute it and/or modify it    *
  *  under the terms of the GNU Library General Public License as    *
  *  published by the Free Software Foundation and appearing in the  *
  *  file COPYING included in the packaging of this file;  either    *
  *  version 2 of the License, or (at your option) any later version.    *
  *                                  *
  *  As a special exception, permission is given to link this program    *
  *  with any version of the KADMOS OCR/ICR engine (a product of     *
  *  reRecognition GmbH, Kreuzlingen), and distribute the resulting  *
  *  executable without including the source code for KADMOS in the  *
  *  source distribution.                        *
  *                                  *
  *  This program is distributed in the hope that it will be useful, *
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of  *
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the   *
  *  GNU General Public License for more details.            *
  *                                  *
  *  You should have received a copy of the GNU General Public       *
  *  License along with this program;  see the file COPYING.  If     *
  *  not, see <http://www.gnu.org/licenses/>.                *
  *                                  *
  ************************************************************************/
 
 #include "gammawidget.h"
 
 #include <qpainter.h>
 #include <qpixmap.h>
 #include <qevent.h>
 
 #include "kgammatable.h"
 
 
 static const int MARGIN = 5;                // margin around display
 static const int NGRID = 4;             // number of grid lines
 
 
 GammaWidget::GammaWidget(KGammaTable *table, QWidget *parent)
     : QWidget(parent)
 {
     mTable = table;
     connect(mTable, &KGammaTable::tableChanged, this, QOverload<>::of(&QWidget::repaint));
 
     QSizePolicy pol(QSizePolicy::MinimumExpanding, QSizePolicy::MinimumExpanding);
     setSizePolicy(pol);
 }
 
 void GammaWidget::paintEvent(QPaintEvent *ev)
 {
     QPainter p(this);
 
     // Calculate the minimum display size
     int size = qMin(width(), height()) - 2 * MARGIN;
 
     // Limit the painting area to a square of that size
     p.setViewport(MARGIN, MARGIN, size, size);
     p.setWindow(0, 0, size, size);
 
     // background and outer frame
     p.setBrush(palette().base());
     p.setPen(palette().windowText().color());
     p.drawRect(0, 0, size, size);
 
     // grid lines
     p.setPen(QPen(palette().mid().color(), 0, Qt::DotLine));
     int step = size / (NGRID + 1);
     for (int l = 1; l <= NGRID; ++l) {
         p.drawLine(1, l * step, size - 1, l * step);    // horizontal line
         p.drawLine(l * step, 1, l * step, size - 1);    // vertical line
     }
 
     if (mTable == nullptr) return;              // no values to draw
 
     // the gamma curve
     p.setPen(palette().highlight().color());
 
     const int *vals = mTable->getTable();
     const int nvals = mTable->tableSize();
     const int maxval = KGammaTable::valueRange;
     p.setWindow(0, 0, nvals, maxval);
 
     int py = maxval-vals[0];
     for (int x = 1; x<nvals; ++x)
     {
         int y = maxval-vals[x];
         p.drawLine(x-1, py, x, y);
         py = y;
     }
 }
 
 QSize GammaWidget::sizeHint() const
 {
     return (QSize(256 + 2 * MARGIN, 256 + 2 * MARGIN));
 }