libcruft-util/matrix2.cpp
Danny Robson f6056153e3 rename root namespace from util to cruft
This places, at long last, the core library code into the same namespace
as the extended library code.
2018-08-05 14:42:02 +10:00

50 lines
1.5 KiB
C++

/*
* 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/.
*
* Copyright 2015 Danny Robson <danny@nerdcruft.net>
*/
#include "matrix.hpp"
using cruft::matrix;
///////////////////////////////////////////////////////////////////////////////
template <std::size_t Rows, std::size_t Cols, typename T>
T
cruft::determinant (const matrix<Rows,Cols,T> &m)
{
static_assert (Rows == 2 && Cols == 2);
return m[0][0] * m[1][1] - m[0][1] * m[1][0];
}
template float cruft::determinant (const matrix<2,2,float>&);
template double cruft::determinant (const matrix<2,2,double>&);
///////////////////////////////////////////////////////////////////////////////
template <std::size_t Rows, std::size_t Cols, typename T>
matrix<Rows,Cols,T>
cruft::inverse (const matrix<Rows,Cols,T> &m)
{
static_assert (Rows == 2 && Cols == 2);
return matrix<2,2,T> {{
{ m[1][1], -m[0][1], },
{ -m[1][0], m[0][0], },
}} / determinant (m);
}
//-----------------------------------------------------------------------------
template cruft::matrix<2,2,float> cruft::inverse (const matrix<2,2,float>&);
template cruft::matrix<2,2,double> cruft::inverse (const matrix<2,2,double>&);
///////////////////////////////////////////////////////////////////////////////
template struct cruft::matrix<2,2,float>;
template struct cruft::matrix<2,2,double>;