Transformation.h

/******************************************************************************************************
 * (C) 2014 markummitchell@github.com. This file is part of Engauge Digitizer, which is released      *
 * under GNU General Public License version 2 (GPLv2) or (at your option) any later version. See file *
 * LICENSE or go to gnu.org/licenses for details. Distribution requires prior written permission.     *
 ******************************************************************************************************/
 
#ifndef TRANSFORMATION_H
#define TRANSFORMATION_H
 
#include "CmdMediator.h"
#include "DocumentModelCoords.h"
#include "MainWindowModel.h"
#include <QPointF>
#include <QString>
#include <QTransform>
 
class Transformation
{
  // For unit testing
  friend class TestTransformation;
 
public:
  Transformation();
 
  Transformation &operator=(const Transformation &other);
 
  void identity();
 
  bool operator!=(const Transformation &other);
 
  static QTransform calculateTransformFromLinearCartesianPoints (const QPointF &posFrom0,
                                                                 const QPointF &posFrom1,
                                                                 const QPointF &posFrom2,
                                                                 const QPointF &posTo0,
                                                                 const QPointF &posTo1,
                                                                 const QPointF &posTo2);
 
  static QPointF cartesianFromCartesianOrPolar (const DocumentModelCoords &modelCoords,
                                                const QPointF &posGraphIn);
 
  static QPointF cartesianOrPolarFromCartesian (const DocumentModelCoords &modelCoords,
                                                const QPointF &posGraphIn);
 
  void coordTextForStatusBar (QPointF cursorScreen,
                              QString &coordsScreen,
                              QString &coordsGraph,
                              QString &resolutionGraph);
 
  static double logToLinearCartesian (double xy);
 
  static double logToLinearRadius (double r,
                                   double rCenter);
 
  DocumentModelCoords modelCoords() const;
 
  void printStream (QString indentation,
                    QTextStream &str) const;
 
  void resetOnLoad();
 
  bool transformIsDefined() const;
 
  void transformLinearCartesianGraphToRawGraph (const QPointF &coordGraph,
                                                QPointF &coordScreen) const;
 
  void transformLinearCartesianGraphToScreen (const QPointF &coordGraph,
                                              QPointF &coordScreen) const;
 
  QTransform transformMatrix () const;
 
  void transformRawGraphToLinearCartesianGraph (const QPointF &pointRaw,
                                                QPointF &pointLinearCartesian) const;
 
  void transformRawGraphToScreen (const QPointF &pointRaw,
                                  QPointF &pointScreen) const;
 
  void transformScreenToLinearCartesianGraph (const QPointF &pointScreen,
                                              QPointF &pointLinearCartesian) const;
 
  void transformScreenToRawGraph (const QPointF &coordScreen,
                                  QPointF &coordGraph) const;
 
  void update (bool fileIsLoaded,
               const CmdMediator &cmdMediator,
               const MainWindowModel &modelMainWindow);
 
private:
 
  // No need to display values like 1E-17 when it is insignificant relative to the range
  double roundOffSmallValues (double value, double range);
 
  // Model coords are set upon entry from CmdMediator
  void setModelCoords (const DocumentModelCoords &modelCoords,
                       const MainWindowModel &modelMainWindow);
 
  // Compute transform from screen and graph points. The 3x3 matrices are handled as QTransform since QMatrix is deprecated
  void updateTransformFromMatrices (const QTransform &matrixScreen,
                                    const QTransform &matrixGraph);
 
  // State variable
  bool m_transformIsDefined;
 
  // Transform between cartesian screen coordinates and cartesian graph coordinates
  QTransform m_transform;
 
  // Coordinates information from last time the transform was updated. Only defined if  m_transformIsDefined is true
  DocumentModelCoords m_modelCoords;
 
  // Formatting information
  MainWindowModel m_modelMainWindow;
};
 
const Transformation &operator<< (std::ostringstream &str,
                                  const Transformation &transformation);
 
#endif // TRANSFORMATION_H