src/basics.h

/*
 *  LDForge: LDraw parts authoring CAD
 *  Copyright (C) 2013 - 2015 Teemu Piippo
 *
 *  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/>.
 */

#pragma once
#include <QString>
#include <QObject>
#include <QStringList>
#include <QMetaType>
#include <QVector>
#include <QVector3D>
#include <QSharedPointer>
#include "macros.h"

class LDObject;
class QFile;
class QTextStream;
class Matrix;
class LDDocument;

using int8 = qint8;
using int16 = qint16;
using int32 = qint32;
using int64 = qint64;
using uint8 = quint8;
using uint16 = quint16;
using uint32 = quint32;
using uint64 = quint64;
using LDObjectPtr = QSharedPointer<LDObject>;
using LDObjectList = QList<LDObjectPtr>;
using LDObjectWeakPtr = QWeakPointer<LDObject>;
using LDObjectWeakList = QList<LDObjectWeakPtr>;
using LDDocumentPtr = QSharedPointer<LDDocument>;
using LDDocumentWeakPtr = QWeakPointer<LDDocument>;
using real = double;

template<typename T, typename R>
using Pair = std::pair<T, R>;

//
// A mathematical 3 x 3 matrix
//
class Matrix
{
public:
	Matrix() {}
	Matrix (const std::initializer_list<double>& vals);

	// Constructs a matrix all 9 elements initialized to the same value.
	Matrix (double fillval);

	// Constructs a matrix with a C-array.
	// note: @vals is expected to have exactly 9 elements.
	Matrix (double vals[]);

	// Calculates the matrix's determinant.
	double			getDeterminant() const;

	// Multiplies this matrix with @other
	// note: a.mult(b) is not equivalent to b.mult(a)!
	Matrix			mult (const Matrix& other) const;

	// Prints the matrix to stdout.
	void			dump() const;

	// Yields a string representation of the matrix.
	QString			toString() const;

	// Zeroes the matrix out.
	void			zero();

	// Assigns the matrix values to the values of @other.
	Matrix&			operator= (const Matrix& other);

	// Returns a mutable reference to a value by @idx
	inline double& value (int idx)
	{
		return m_vals[idx];
	}

	// An overload of value() for const matrices.
	inline const double& value (int idx) const
	{
		return m_vals[idx];
	}

	// An operator overload for mult().
	inline Matrix operator* (const Matrix& other) const
	{
		return mult (other);
	}

	// An operator overload for value().
	inline double& operator[] (int idx)
	{
		return value (idx);
	}

	// An operator overload for value() const.
	inline const double& operator[] (int idx) const
	{
		return value (idx);
	}

	// Checks whether the two matrices have the same values.
	bool operator== (const Matrix& other) const;

private:
	double m_vals[9];
};

extern const Matrix IdentityMatrix;

static const double Pi = 3.14159265358979323846;

template<typename T>
T clamp (T a, T min, T max)
{
	return (a > max) ? max : (a < min) ? min : a;
}

template<typename T>
T min (T a, T b)
{
	return (a < b) ? a : b;
}

template<typename T>
T max (T a, T b)
{
	return (a > b) ? a : b;
}

template<typename T>
T abs (T a)
{
	return (a >= 0) ? a : -a;
}

template<typename T>
bool isZero (T a)
{
	return abs<T> (a) < 0.00001;
}

template<typename T>
const char* plural (T n)
{
	return (not isZero (n - 1)) ? "s" : "";
}

template<typename T>
bool isInteger (T a)
{
	return (abs (a - floor(a)) < 0.00001) or (abs (a - ceil(a)) < 0.00001);
}

template<typename T>
bool isInRange (T a, T b, T c)
{
	return a >= b and a <= c;
}

template<typename T>
void removeDuplicates (T& a)
{
	std::sort (a.begin(), a.end());
	a.erase (std::unique (a.begin(), a.end()), a.end());
}

//
// Returns true if first arg is equal to any of the other args
//
template<typename T, typename Arg, typename... Args>
bool Eq (T const& a, Arg const& arg, Args const&... args)
{
	if (a == arg)
		return true;

	return Eq (a, args...);
}

template<typename T>
bool Eq (T const&)
{
	return false;
}