boost/gil/extension/numeric/affine.hpp
/*
Copyright 2005-2007 Adobe Systems Incorporated
Use, modification and distribution are subject to the Boost Software License,
Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
http://www.boost.org/LICENSE_1_0.txt).
*/
/*************************************************************************************************/
#ifndef BOOST_GIL_EXTENSION_NUMERIC_AFFINE_HPP
#define BOOST_GIL_EXTENSION_NUMERIC_AFFINE_HPP
#include <boost/gil/utilities.hpp> // point2
////////////////////////////////////////////////////////////////////////////////////////
/// \file
/// \brief support for affine transformations
/// \author Lubomir Bourdev and Hailin Jin \n
/// Adobe Systems Incorporated
/// \date 2005-2007 \n
///
////////////////////////////////////////////////////////////////////////////////////////
namespace boost { namespace gil {
////////////////////////////////////////////////////////////////////////////////////////
///
/// Simple matrix to do 2D affine transformations. It is actually 3x3 but the last column is [0 0 1]
///
////////////////////////////////////////////////////////////////////////////////////////
template <typename T>
class matrix3x2 {
public:
matrix3x2() : a(1), b(0), c(0), d(1), e(0), f(0) {}
matrix3x2(T A, T B, T C, T D, T E, T F) : a(A),b(B),c(C),d(D),e(E),f(F) {}
matrix3x2(const matrix3x2& mat) : a(mat.a), b(mat.b), c(mat.c), d(mat.d), e(mat.e), f(mat.f) {}
matrix3x2& operator=(const matrix3x2& m) { a=m.a; b=m.b; c=m.c; d=m.d; e=m.e; f=m.f; return *this; }
matrix3x2& operator*=(const matrix3x2& m) { (*this) = (*this)*m; return *this; }
static matrix3x2 get_rotate(T rads) { T c=std::cos(rads); T s=std::sin(rads); return matrix3x2(c,s,-s,c,0,0); }
static matrix3x2 get_translate(const point2<T>& t) { return matrix3x2(1 ,0,0,1 ,t.x,t.y); }
static matrix3x2 get_translate(T x, T y) { return matrix3x2(1 ,0,0,1 ,x, y ); }
static matrix3x2 get_scale (const point2<T>& s) { return matrix3x2(s.x,0,0,s.y,0 ,0 ); }
static matrix3x2 get_scale (T x, T y) { return matrix3x2(x, 0,0,y, 0 ,0 ); }
static matrix3x2 get_scale (T s) { return matrix3x2(s ,0,0,s ,0 ,0 ); }
T a,b,c,d,e,f;
};
template <typename T> BOOST_FORCEINLINE
matrix3x2<T> operator*(const matrix3x2<T>& m1, const matrix3x2<T>& m2) {
return matrix3x2<T>(
m1.a * m2.a + m1.b * m2.c,
m1.a * m2.b + m1.b * m2.d,
m1.c * m2.a + m1.d * m2.c,
m1.c * m2.b + m1.d * m2.d,
m1.e * m2.a + m1.f * m2.c + m2.e,
m1.e * m2.b + m1.f * m2.d + m2.f );
}
template <typename T, typename F> BOOST_FORCEINLINE
point2<F> operator*(const point2<T>& p, const matrix3x2<F>& m) {
return point2<F>(m.a*p.x + m.c*p.y + m.e, m.b*p.x + m.d*p.y + m.f);
}
////////////////////////////////////////////////////////////////////////////////////////
/// Define affine mapping that transforms the source coordinates by the affine transformation
////////////////////////////////////////////////////////////////////////////////////////
/*
template <typename MapFn>
concept MappingFunctionConcept {
typename mapping_traits<MapFn>::result_type; where PointNDConcept<result_type>;
template <typename Domain> { where PointNDConcept<Domain> }
result_type transform(MapFn&, const Domain& src);
};
*/
template <typename T> struct mapping_traits;
template <typename F>
struct mapping_traits<matrix3x2<F> > {
typedef point2<F> result_type;
};
template <typename F, typename F2> BOOST_FORCEINLINE
point2<F> transform(const matrix3x2<F>& mat, const point2<F2>& src) { return src * mat; }
} } // namespace boost::gil
#endif // BOOST_GIL_EXTENSION_NUMERIC_AFFINE_HPP
