interval.h

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/*
 * Copyright 2007 Michael Sloan <mgsloan@gmail.com>
 *
 * Original Rect/Range code by:
 *   Lauris Kaplinski <lauris@kaplinski.com>
 *   Nathan Hurst <njh@mail.csse.monash.edu.au>
 *   bulia byak <buliabyak@users.sf.net>
 *   MenTaLguY <mental@rydia.net>
 *
 * 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_INTERVAL_H
#define LIB2GEOM_SEEN_INTERVAL_H
 
#include <boost/none.hpp>
#include <boost/operators.hpp>
#include <2geom/coord.h>
#include <2geom/math-utils.h>
#include <2geom/generic-interval.h>
#include <2geom/int-interval.h>
 
namespace Geom {
 
class Interval
    : public GenericInterval<Coord>
{
    using Base = GenericInterval<Coord>;
public:
 
    constexpr Interval() = default;
    explicit constexpr Interval(Coord u) : Base(u) {}
    constexpr Interval(Coord u, Coord v) : Base(u, v) {}
    constexpr Interval(IntInterval const &i) : Base(i.min(), i.max()) {}
    constexpr Interval(Base const &b) : Base(b) {}
 
    template <typename InputIterator>
    static Interval from_range(InputIterator start, InputIterator end) {
        return Base::from_range(start, end);
    }
    static Interval from_array(Coord const *c, unsigned n) {
        return Base::from_array(c, n);
    }
 
    bool isFinite() const {
        return std::isfinite(min()) && std::isfinite(max());
    }
    constexpr Coord valueAt(Coord t) const {
        return lerp(t, min(), max());
    }
    constexpr Coord timeAt(Coord v) const {
        return (v - min()) / extent();
    }
    constexpr Coord nearestTime(Coord v) const {
        if (v <= min()) return 0;
        if (v >= max()) return 1;
        return timeAt(v);
    }
 
 
    constexpr bool interiorContains(Coord val) const { return min() < val && val < max(); }
    constexpr bool interiorContains(Interval const &val) const { return min() < val.min() && val.max() < max(); }
    constexpr bool lowerContains(Coord val) const { return min() <= val && val < max(); }
    constexpr bool lowerContains(Interval const &val) const { return min() <= val.min() && val.max() < max(); }
    constexpr bool upperContains(Coord val) { return min() < val && val <= max(); }
    constexpr bool upperContains(Interval const &val) const { return min() < val.min() && val.max() <= max(); }
    constexpr bool interiorIntersects(Interval const &val) const {
        return std::max(min(), val.min()) < std::min(max(), val.max());
    }
 
    // IMPL: ScalableConcept
    constexpr Interval &operator*=(Coord s) {
        using std::swap;
        _b[0] *= s;
        _b[1] *= s;
        if (s < 0) swap(_b[0], _b[1]);
        return *this;
    }
    constexpr Interval &operator/=(Coord s) {
        using std::swap;
        _b[0] /= s;
        _b[1] /= s;
        if (s < 0) swap(_b[0], _b[1]);
        return *this;
    }
    constexpr Interval &operator*=(Interval const &o) {
        // TODO implement properly
        Coord mn = min(), mx = max();
        expandTo(mn * o.min());
        expandTo(mn * o.max());
        expandTo(mx * o.min());
        expandTo(mx * o.max());
        return *this;
    }
    constexpr bool operator==(IntInterval const &ii) const {
        return min() == Coord(ii.min()) && max() == Coord(ii.max());
    }
    constexpr bool operator==(Interval const &other) const {
        return Base::operator==(other);
    }
 
 
    IntInterval roundOutwards() const {
        return IntInterval(floor(min()), ceil(max()));
    }
    OptIntInterval roundInwards() const {
        IntCoord u = ceil(min()), v = floor(max());
        if (u > v) return {};
        return IntInterval(u, v);
    }
};
 
class OptInterval
    : public GenericOptInterval<Coord>
{
    using Base = GenericOptInterval<Coord>;
public:
    using Base::Base;
    using Base::operator==;
    using Base::operator!=;
 
    constexpr OptInterval(Base const &b) : Base(b) {}
 
    constexpr OptInterval(IntInterval const &i) : Base(Interval(i)) {}
    constexpr OptInterval(OptIntInterval const &i) {
        if (i) *this = Interval(*i);
    }
};
 
// functions required for Python bindings
inline Interval unify(Interval const &a, Interval const &b) {
    return a | b;
}
inline OptInterval intersect(Interval const &a, Interval const &b) {
    return a & b;
}
 
} // namespace Geom
 
// Structured binding support
template <> struct std::tuple_size<Geom::Interval> : std::integral_constant<size_t, 2> {};
template <size_t I> struct std::tuple_element<I, Geom::Interval> { using type = Geom::Coord; };
 
// Hash support
template <> struct std::hash<Geom::Interval> : std::hash<Geom::GenericInterval<Geom::Coord>> {};
 
#endif // LIB2GEOM_SEEN_INTERVAL_H
 
/*
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*/
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