concepts.h revision 40742313779ee5e43be93a9191f1c86412cf183b
/**
* \file
* \brief Template concepts used by 2Geom
*//*
* Copyright 2007 Michael Sloan <mgsloan@gmail.com>
*
* This library is free software; you can redistribute it and/or
* modify it either under the terms of the GNU Lesser General Public
* License version 2.1 as published by the Free Software Foundation
* (the "LGPL") or, at your option, under the terms of the Mozilla
* Public License Version 1.1 (the "MPL"). If you do not alter this
* notice, a recipient may use your version of this file under either
* the MPL or the LGPL.
*
* You should have received a copy of the LGPL along with this library
* in the file COPYING-LGPL-2.1; if not, output to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
* You should have received a copy of the MPL along with this library
* in the file COPYING-MPL-1.1
*
* The contents of this file are subject to the Mozilla Public License
* Version 1.1 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
* OF ANY KIND, either express or implied. See the LGPL or the MPL for
* the specific language governing rights and limitations.
*/
#ifndef LIB2GEOM_SEEN_CONCEPTS_H
#define LIB2GEOM_SEEN_CONCEPTS_H
#include <2geom/sbasis.h>
#include <2geom/interval.h>
#include <2geom/point.h>
#include <2geom/rect.h>
#include <vector>
#include <boost/concept_check.hpp>
#include <2geom/forward.h>
namespace Geom {
//forward decls
template <typename T> struct ResultTraits;
template <> struct ResultTraits<double> {
typedef OptInterval bounds_type;
typedef SBasis sb_type;
};
template <> struct ResultTraits<Point> {
typedef OptRect bounds_type;
typedef D2<SBasis> sb_type;
};
//A concept for one-dimensional functions defined on [0,1]
template <typename T>
struct FragmentConcept {
typedef typename T::output_type OutputType;
typedef typename ResultTraits<OutputType>::bounds_type BoundsType;
typedef typename ResultTraits<OutputType>::sb_type SbType;
T t;
double d;
OutputType o;
bool b;
BoundsType i;
Interval dom;
std::vector<OutputType> v;
unsigned u;
SbType sb;
void constraints() {
t = T(o);
b = t.isZero();
b = t.isConstant();
b = t.isFinite();
o = t.at0();
o = t.at1();
o = t.valueAt(d);
o = t(d);
v = t.valueAndDerivatives(d, u-1);
//Is a pure derivative (ignoring others) accessor ever much faster?
//u = number of values returned. first val is value.
sb = t.toSBasis();
t = reverse(t);
i = bounds_fast(t);
i = bounds_exact(t);
i = bounds_local(t, dom);
/*With portion, Interval makes some sense, but instead I'm opting for
doubles, for the following reasons:
A) This way a reversed portion may be specified
B) Performance might be a bit better for piecewise and such
C) Interval version provided below
*/
t = portion(t, d, d);
}
};
template <typename T>
inline T portion(const T& t, const Interval& i) { return portion(t, i.min(), i.max()); }
template <typename T>
struct NearConcept {
T a, b;
double tol;
bool res;
void constraints() {
res = are_near(a, b, tol);
}
};
template <typename T>
struct OffsetableConcept {
T t;
typename T::output_type d;
void constraints() {
t = t + d; t += d;
t = t - d; t -= d;
}
};
template <typename T>
struct ScalableConcept {
T t;
typename T::output_type d;
void constraints() {
t = -t;
t = t * d; t *= d;
t = t / d; t /= d;
}
};
template <typename T>
struct AddableConcept {
T i, j;
void constraints() {
i += j; i = i + j;
i -= j; i = i - j;
}
};
template <typename T>
struct MultiplicableConcept {
T i, j;
void constraints() {
i *= j; i = i * j;
}
};
} // end namespace Geom
#endif // LIB2GEOM_SEEN_CONCEPTS_H
/*
Local Variables:
mode:c++
c-file-style:"stroustrup"
c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
indent-tabs-mode:nil
fill-column:99
End:
*/
// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :