length.h

/*
 * Copyright © 2017 - 2019 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 LENGTH
#define LENGTH
 
#include <QMetaType>
#include <QString>
#include <QtGlobal>
 
 
class length
{
public:
    enum unit {
        cm,    
        in,    
        mm,    
        pt     
    };
 
    length() : _length(0) {
 
    }
 
    length(qreal l, unit u) {
        set(l, u);
    }
 
    explicit length(QString lstring, bool *ok=0) {
        bool myOk = set(lstring);
        if (ok)
            *ok = myOk;
    }
 
    qreal get(unit u) const;
 
    void set(qreal l, unit u);
 
    bool set(QString lstring);
 
    bool isNonPositive() const {
        return (_length <= 0);
    }
 
    operator QString() const {
        return QString("%1mm").arg(get(mm));
    }
 
    bool operator==(const length other) const
    {
        return _length == other._length;
    }
 
    const length operator+(const length rhs) const
    {
        length result;
        result._length = _length + rhs._length;
        return result;
    }
 
    const length operator-(const length rhs) const
    {
        length result;
        result._length = _length - rhs._length;
        return result;
    }
 
    const length operator/(const qreal div) const
    {
        length result;
        result._length = _length/div;
        return result;
    }
 
private:
    // Length in 1/360 mm
    qreal _length;
};
 
// Makes "length" known to QMetaType
Q_DECLARE_METATYPE(length)
 
#endif