resolution.h

/*
 * Copyright © 2017 - 2020 Stefan Kebekus <stefan.kebekus@math.uni-freiburg.de>
 *
 * 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 3 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, see <http://www.gnu.org/licenses/>.
 */


#ifndef RESOLUTION
#define RESOLUTION

#include <QMetaType>
#include <QString>
#include <QtGlobal>

#include "length.h"


class resolution
{
  friend resolution qMax(const resolution res1, const resolution res2);

 public:
  enum unit {
    dpcm,   
    dpi,    
    dpm,    
  };
  
  resolution() : _resolution(0) {
  }

  resolution(qreal l, unit u) {
    set(l, u);
  }
  
  qreal get(unit u) const;

  void set(qreal l, unit u);

  bool isNonPositive() const {
    return (_resolution <= 0);
  }

  bool isZero() const {
    return  qFuzzyIsNull(_resolution);
  }

  bool isValid() const {
    qreal ridpi = get(dpi);
    return (ridpi >= minResDPI) && (ridpi <= maxResDPI);
  }
  
  operator QString() const {
    return QString("%1dpi").arg(get(dpi));
  }

  bool operator==(const resolution other) const
  {
    return _resolution == other._resolution;
  }

  static const int minResDPI = 10;
  
  static const int maxResDPI = 10000;

  
 private:
  // Resolution in 1/100 mm
  qreal _resolution;
};


inline length operator/(qreal numerator, const resolution denominator) {
  return length(numerator/denominator.get(resolution::dpi), length::in);
}

inline resolution operator/(qreal numerator, const length denominator) {
  return resolution(numerator/denominator.get(length::in), resolution::dpi);
}

inline resolution qMax(const resolution res1, const resolution res2)
{
  return res1._resolution > res2._resolution ? res1 : res2;
}


// Makes "resolution" known to QMetaType
Q_DECLARE_METATYPE(resolution)

#endif