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splinegraph.h

/* splinegraph.h   Qt widget for entering a spline curve graphically
 * 
 * Copyright 2001 Ken McMillan
 *
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#include <vector>
#include <qwidget.h>
#include <qpainter.h>

class SplineInterpolator {
 public:
  vector<float> xpts,ypts;
  virtual float operator()(float) = 0;
  virtual void recalculate() = 0;
};

class SplineGraph : public QWidget {
  Q_OBJECT
public:
  SplineGraph(SplineInterpolator *, float _xmin, float _xmax, float _ymin, float _ymax);
  void setXRange(float,float);
  void setYRange(float,float);
  void setPoints(vector<float> &_xpts, vector<float> &_ypts);

protected:
  virtual void paintEvent( QPaintEvent*);
  void mousePressEvent(QMouseEvent *);
  void mouseReleaseEvent ( QMouseEvent *);
  void mouseMoveEvent ( QMouseEvent * );

private:
  SplineInterpolator *interp;
  float xmin,xmax,ymin,ymax,xright,xleft; 
  QSize graphSize;
  int borderwidth;
  int gtop,gbottom,gright,gleft;
  QPixmap* _buffer;
  bool draggingPoint;
  int draggedPoint;
  float XScaleUnit,YScaleUnit;

  int xPoint(float x);
  int yPoint(float y);
  float xPointInv(int x);
  float yPointInv(int y);
  void drawGraph();
  void drawScale(QPainter &p, 
                 Orientation scaleDir, 
                 int pos, int tickDir);
  
};

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