Files
pilotclient/src/blackmisc/pqbase.h
2014-01-08 00:58:56 +00:00

404 lines
15 KiB
C++

/* Copyright (C) 2013 VATSIM Community / authors
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef BLACKMISC_PQBASE_H
#define BLACKMISC_PQBASE_H
#include "blackmisc/valueobject.h"
#include "blackmisc/debug.h"
#include "blackmisc/mathematics.h"
#include <QCoreApplication>
#include <QtDBus/QDBusArgument>
#include <QString>
#include <QtGlobal>
#include <QDebug>
#include <QSharedData>
#include <QSharedDataPointer>
namespace BlackMisc
{
namespace PhysicalQuantities
{
/*!
* \brief Base class for all units, such as meter, hertz.
*/
class CMeasurementUnit : public CValueObject
{
protected:
/*!
* Abstract strategy pattern that encapsulates a unit conversion strategy.
*/
class Converter : public QSharedData
{
public:
/*!
* Virtual destructor.
*/
virtual ~Converter() {}
/*!
* Convert from this unit to default unit.
* \param factor
* \return
*/
virtual double toDefault(double factor) const = 0;
/*!
* Convert from default unit to this unit.
* \param factor
* \return
*/
virtual double fromDefault(double factor) const = 0;
};
/*!
* \brief Converter for default values, such as None, used with public constructor
*/
struct NilConverter : public Converter
{
virtual double toDefault(double) const { return 0.0; }
virtual double fromDefault(double) const { return 0.0; }
};
/*!
* Concrete strategy pattern for converting unit that does nothing.
*/
struct IdentityConverter : public Converter
{
virtual double toDefault(double factor) const { return factor; }
virtual double fromDefault(double factor) const { return factor; }
};
/*!
* Concrete strategy pattern for converting unit with linear conversion.
* \tparam Policy a policy class with static method factor() returning double
*/
template <class Policy>
struct LinearConverter : public Converter
{
virtual double toDefault(double factor) const { return factor * Policy::factor(); }
virtual double fromDefault(double factor) const { return factor / Policy::factor(); }
};
/*!
* Concrete strategy pattern for converting unit with offset linear conversion.
* \tparam Policy a policy class with static methods factor() and offset() returning double
*/
template <class Policy>
struct AffineConverter : public Converter
{
virtual double toDefault(double factor) const { return (factor - Policy::offset()) * Policy::factor(); }
virtual double fromDefault(double factor) const { return factor / Policy::factor() + Policy::offset(); }
};
/*!
* Concrete strategy pattern for converting unit with one subdivision conversion.
* \tparam FactorPolicy a policy class with static method factor() returning double
* \tparam SubdivPolicy a policy class with static methods fraction() and subfactor() returning double
*/
template <class FactorPolicy, class SubdivPolicy>
struct SubdivisionConverter : public Converter
{
virtual double toDefault(double factor) const
{
using BlackMisc::Math::CMath;
double part2 = CMath::fract(factor) * SubdivPolicy::fraction();
factor = CMath::trunc(factor) + part2 / SubdivPolicy::subfactor();
return factor * FactorPolicy::factor();
}
virtual double fromDefault(double factor) const
{
using BlackMisc::Math::CMath;
factor /= FactorPolicy::factor();
double part2 = CMath::fract(factor) * SubdivPolicy::subfactor();
return CMath::trunc(factor) + part2 / SubdivPolicy::fraction();
}
};
/*!
* Concrete strategy pattern for converting unit with two subdivision conversions.
* \tparam FactorPolicy a policy class with static method factor() returning double
* \tparam SubdivPolicy a policy class with static methods fraction() and subfactor() returning double
*/
template <class FactorPolicy, class SubdivPolicy>
struct SubdivisionConverter2 : public Converter
{
virtual double toDefault(double factor) const
{
using BlackMisc::Math::CMath;
double part2 = CMath::fract(factor) * SubdivPolicy::fraction();
double part3 = CMath::fract(part2) * SubdivPolicy::fraction();
factor = CMath::trunc(factor) + (CMath::trunc(part2) + part3 / SubdivPolicy::subfactor()) / SubdivPolicy::subfactor();
return factor * FactorPolicy::factor();
}
virtual double fromDefault(double factor) const
{
using BlackMisc::Math::CMath;
factor /= FactorPolicy::factor();
double part2 = CMath::fract(factor) * SubdivPolicy::subfactor();
double part3 = CMath::fract(part2) * SubdivPolicy::subfactor();
return CMath::trunc(factor) + (CMath::trunc(part2) + part3 / SubdivPolicy::fraction()) / SubdivPolicy::fraction();
}
};
//! Metapolicy that can be used to modify template parameters of converters
//! @{
struct One
{
static double factor() { return 1; } //!< factor \return
};
template <class Policy>
struct Two
{
static double factor() { return Policy::factor() * 2.0; } //!< factor \return
};
template <class Policy>
struct Milli
{
static double factor() { return Policy::factor() / 1000.0; } //!< factor \return
};
template <class Policy>
struct Centi
{
static double factor() { return Policy::factor() / 100.0; } //!< factor \return
};
template <class Policy>
struct Hecto
{
static double factor() { return Policy::factor() * 100.0; } //!< factor \return
};
template <class Policy>
struct Kilo
{
static double factor() { return Policy::factor() * 1000.0; } //!< factor \return
};
template <class Policy>
struct Mega
{
static double factor() { return Policy::factor() * 1e+6; } //!< factor \return
};
template <class Policy>
struct Giga
{
static double factor() { return Policy::factor() * 1e+9; } //!< factor \return
};
template <int Subfactor>
struct InEachHundred
{
static double fraction() { return 100.0f; } //!< fraction \return
static double subfactor() { return float(Subfactor); } //!< subfactor \return
};
//! @}
private:
QString m_name; //!< name, e.g. "meter"
QString m_symbol; //!< unit name, e.g. "m"
double m_epsilon; //!< values with differences below epsilon are the equal
int m_displayDigits; //!< standard rounding for string conversions
QSharedDataPointer<Converter> m_converter; //!< strategy pattern allows an arbitrary conversion method as per object
protected:
/*!
* Construct a unit with custom conversion
* \param name
* \param symbol
* \param displayDigits
* \param epsilon
*/
template <class Converter>
CMeasurementUnit(const QString &name, const QString &symbol, const Converter &, int displayDigits, double epsilon)
: m_name(name), m_symbol(symbol), m_epsilon(epsilon), m_displayDigits(displayDigits), m_converter(new Converter)
{}
/*!
* \brief String for streaming operators is full name
* \return
*/
virtual QString stringForStreaming() const
{
return this->getName(false);
}
/*!
* \brief Name as stringification
* \param i18n
* \return
*/
virtual QString convertToQString(bool i18n = false) const
{
return this->getSymbol(i18n);
}
/*!
* \brief Stream to DBus
* \param argument
*/
virtual void marshallToDbus(QDBusArgument &argument) const
{
argument << this->m_symbol;
}
/*!
* \brief Stream from DBus
* \param argument
*/
virtual void unmarshallFromDbus(const QDBusArgument &)
{
// the concrete implementations will override this default
// this is required so I can also stream None
(*this) = CMeasurementUnit::None();
}
public:
/*!
* \brief Default constructor for meta system
* \remarks Only public because the need, to use this with the metasystem
*/
CMeasurementUnit() : m_name("none"), m_symbol(""), m_epsilon(0), m_displayDigits(0), m_converter(new NilConverter())
{}
/*!
* \brief Virtual method to return QVariant, used with DBUS QVariant lists
* \return
*/
virtual QVariant toQVariant() const
{
// used with None!
return QVariant::fromValue(*this);
}
/*!
* \brief Equal operator ==
* \param other
* \return
*/
bool operator == (const CMeasurementUnit &other) const;
/*!
* \brief Unequal operator !=
* \param other
* \return
*/
bool operator != (const CMeasurementUnit &other) const;
/*!
* \brief Name such as "meter"
* \param i18n
* \return
*/
QString getName(bool i18n = false) const
{
return i18n ? QCoreApplication::translate("CMeasurementUnit", this->m_name.toStdString().c_str()) : this->m_name;
}
/*!
* \brief Unit name such as "m"
* \param i18n
* \return
*/
QString getSymbol(bool i18n = false) const
{
return i18n ? QCoreApplication::translate("CMeasurementUnit", this->m_symbol.toStdString().c_str()) : this->m_symbol;
}
/*!
* \brief Rounded value
* \param value
* \param digits
* \return
*/
double roundValue(double value, int digits = -1) const;
/*!
* Rounded string utility method, virtual so units can have
* specialized formatting
* \param value
* \param digits
* \param i18n
* \return
*/
virtual QString makeRoundedQString(double value, int digits = -1, bool i18n = false) const;
/*!
* \brief Value rounded with unit, e.g. "5.00m", "30kHz"
* \param value
* \param digits
* \param i18n
* \return
*/
virtual QString makeRoundedQStringWithUnit(double value, int digits = -1, bool i18n = false) const;
/*!
* \brief Threshold for rounding
* \return
*/
double getEpsilon() const
{
return this->m_epsilon;
}
/*!
* \brief getDisplayDigits
* \return
*/
int getDisplayDigits() const
{
return this->m_displayDigits;
}
/*!
* Convert from other unit to this unit.
* \param
*/
double convertFrom(double value, const CMeasurementUnit &unit) const;
/*!
* \brief Is given value <= epsilon?
* \param value
* \return
*/
bool isEpsilon(double value) const
{
if (value == 0) return true;
return abs(value) <= this->m_epsilon;
}
// --------------------------------------------------------------------
// -- static
// --------------------------------------------------------------------
/*!
* \brief Unit from symbol
* \param symbol must be a valid unit symbol (without i18n) or empty string (empty means default unit)
* \return
*/
template <class U> static const U &unitFromSymbol(const QString &symbol)
{
if (symbol.isEmpty()) return U::defaultUnit();
const QList<U> &units = U::allUnits();
for (int i = 0; i < units.size(); ++i)
{
if (units.at(i).getSymbol() == symbol) return units.at(i);
}
qFatal("Illegal unit name");
return U::defaultUnit(); // just suppress "not all control paths return a value"
}
/*!
* \brief Dimensionless unit
* \return
*/
static CMeasurementUnit &None()
{
static CMeasurementUnit none("none", "", NilConverter(), 0, 0);
return none;
}
};
} // namespace
} // namespace
#endif // guard