generic-rect.h

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/*
 * Authors:
 *   Michael Sloan <mgsloan@gmail.com>
 *   Krzysztof Kosiński <tweenk.pl@gmail.com>
 * Copyright 2007-2011 Authors
 *
 * 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.
 *
 * Authors of original rect class:
 *   Lauris Kaplinski <lauris@kaplinski.com>
 *   Nathan Hurst <njh@mail.csse.monash.edu.au>
 *   bulia byak <buliabyak@users.sf.net>
 *   MenTaLguY <mental@rydia.net>
 */
 
#ifndef LIB2GEOM_SEEN_GENERIC_RECT_H
#define LIB2GEOM_SEEN_GENERIC_RECT_H
 
#include <limits>
#include <iostream>
#include <optional>
#include <2geom/coord.h>
 
namespace Geom {
 
template <typename C>
class GenericOptRect;
 
template <typename C>
class GenericRect
    : CoordTraits<C>::RectOps
{
    using CInterval = typename CoordTraits<C>::IntervalType;
    using CPoint = typename CoordTraits<C>::PointType;
    using CRect = typename CoordTraits<C>::RectType;
    using OptCRect = typename CoordTraits<C>::OptRectType;
protected:
    CInterval f[2];
public:
    using D1Value = CInterval;
    using D1Reference = CInterval &;
    using D1ConstReference = CInterval const &;
 
 
    GenericRect() = default;
    GenericRect(CInterval const &a, CInterval const &b) : f{a, b} {}
    GenericRect(CPoint const &a, CPoint const &b) : f{{a[X], b[X]}, {a[Y], b[Y]}} {}
    GenericRect(C x0, C y0, C x1, C y1) : f{{x0, x1}, {y0, y1}} {}
    template <typename InputIterator>
    static CRect from_range(InputIterator start, InputIterator end) {
        assert(start != end);
        CPoint p1 = *start;
        auto result = CRect(p1, p1);
        for (++start; start != end; ++start) {
            result.expandTo(*start);
        }
        return result;
    }
    static CRect from_array(CPoint const *c, unsigned n) {
        return GenericRect<C>::from_range(c, c + n);
    }
    static CRect from_xywh(C x, C y, C w, C h) {
        return GenericRect<C>::from_xywh(CPoint(x, y), CPoint(w, h));
    }
    static CRect from_xywh(CPoint const &xy, CPoint const &wh) {
        return CRect(xy, xy + wh);
    }
    static CRect infinite() {
        auto min = std::numeric_limits<C>::min();
        auto max = std::numeric_limits<C>::max();
        return CRect(min, min, max, max);
    }
 
    CInterval &operator[](unsigned i)             { return f[i]; }
    CInterval const &operator[](unsigned i) const { return f[i]; }
    CInterval &operator[](Dim2 d)                 { return f[d]; }
    CInterval const &operator[](Dim2 d) const     { return f[d]; }
 
    CPoint min() const { return CPoint(f[X].min(), f[Y].min()); }
    CPoint max() const { return CPoint(f[X].max(), f[Y].max()); }
    CPoint corner(unsigned i) const {
        switch (i % 4) {
            case 0:  return CPoint(f[X].min(), f[Y].min());
            case 1:  return CPoint(f[X].max(), f[Y].min());
            case 2:  return CPoint(f[X].max(), f[Y].max());
            default: return CPoint(f[X].min(), f[Y].max());
        }
    }
 
    C top() const { return f[Y].min(); }
    C bottom() const { return f[Y].max(); }
    C left() const { return f[X].min(); }
    C right() const { return f[X].max(); }
 
    C width() const { return f[X].extent(); }
    C height() const { return f[Y].extent(); }
    Coord aspectRatio() const { return static_cast<Coord>(width()) / height(); }
 
    CPoint dimensions() const { return CPoint(f[X].extent(), f[Y].extent()); }
    CPoint midpoint() const { return CPoint(f[X].middle(), f[Y].middle()); }
 
    C area() const { return f[X].extent() * f[Y].extent(); }
    bool hasZeroArea() const { return f[X].isSingular() || f[Y].isSingular(); }
 
    C maxExtent() const { return std::max(f[X].extent(), f[Y].extent()); }
    C minExtent() const { return std::min(f[X].extent(), f[Y].extent()); }
 
    C distanceSq(CPoint const &p) const {
        return (p - clamp(p)).lengthSq();
    }
 
    CPoint clamp(CPoint const &p) const {
        return CPoint(f[X].clamp(p[X]), f[Y].clamp(p[Y]));
    }
    CPoint nearestEdgePoint(CPoint const &p) const {
        if (!contains(p)) {
            return clamp(p);
        }
        CPoint result = p;
        C cx = f[X].nearestEnd(p[X]);
        C cy = f[Y].nearestEnd(p[Y]);
        if (std::abs(cx - p[X]) <= std::abs(cy - p[Y])) {
            result[X] = cx;
        } else {
            result[Y] = cy;
        }
        return result;
    }
 
 
    bool intersects(GenericRect<C> const &r) const { 
        return f[X].intersects(r[X]) && f[Y].intersects(r[Y]);
    }
    bool contains(GenericRect<C> const &r) const { 
        return f[X].contains(r[X]) && f[Y].contains(r[Y]);
    }
 
    inline bool intersects(OptCRect const &r) const;
    inline bool contains(OptCRect const &r) const;
 
    bool contains(CPoint const &p) const {
        return f[X].contains(p[X]) && f[Y].contains(p[Y]);
    }
 
 
    void setLeft(C val) {
        f[X].setMin(val);
    }
    void setRight(C val) {
        f[X].setMax(val);
    }
    void setTop(C val) {
        f[Y].setMin(val);
    }
    void setBottom(C val) {
        f[Y].setMax(val);
    }
    void setMin(CPoint const &p) {
        f[X].setMin(p[X]);
        f[Y].setMin(p[Y]);
    }
    void setMax(CPoint const &p) {
        f[X].setMax(p[X]);
        f[Y].setMax(p[Y]);
    }
    void expandTo(CPoint const &p)        { 
        f[X].expandTo(p[X]);
        f[Y].expandTo(p[Y]);
    }
    void unionWith(CRect const &b) { 
        f[X].unionWith(b[X]);
        f[Y].unionWith(b[Y]);
    }
    void unionWith(OptCRect const &b);
 
    void expandBy(C amount) {
        expandBy(amount, amount);
    }
 
    void shrinkBy(C amount) { expandBy(-amount); }
 
    void expandBy(C x, C y) { 
        f[X].expandBy(x);
        f[Y].expandBy(y);
    }
 
    void shrinkBy(C x, C y) { expandBy(-x, -y); }
 
    void expandBy(CPoint const &p) {
        expandBy(p[X], p[Y]);
    }
 
 
    GenericRect<C> &operator+=(CPoint const &p) {
        f[X] += p[X];
        f[Y] += p[Y];
        return *this;
    }
    GenericRect<C> &operator-=(CPoint const &p) {
        f[X] -= p[X];
        f[Y] -= p[Y];
        return *this;
    }
    GenericRect<C> &operator|=(CRect const &o) {
        unionWith(o);
        return *this;
    }
    GenericRect<C> &operator|=(OptCRect const &o) {
        unionWith(o);
        return *this;
    }
    bool operator==(CRect const &o) const { return f[X] == o[X] && f[Y] == o[Y]; }
};
 
template <typename C>
class GenericOptRect
    : public std::optional<typename CoordTraits<C>::RectType>
    , boost::equality_comparable< typename CoordTraits<C>::OptRectType
    , boost::equality_comparable< typename CoordTraits<C>::OptRectType, typename CoordTraits<C>::RectType
    , boost::orable< typename CoordTraits<C>::OptRectType
    , boost::andable< typename CoordTraits<C>::OptRectType
    , boost::andable< typename CoordTraits<C>::OptRectType, typename CoordTraits<C>::RectType
      >>>>>
{
    using CInterval = typename CoordTraits<C>::IntervalType;
    using OptCInterval = typename CoordTraits<C>::OptIntervalType;
    using CPoint = typename CoordTraits<C>::PointType;
    using CRect = typename CoordTraits<C>::RectType;
    using OptCRect = typename CoordTraits<C>::OptRectType;
    using Base = std::optional<CRect>;
public:
    using D1Value = CInterval;
    using D1Reference = CInterval &;
    using D1ConstReference = CInterval const &;
 
    GenericOptRect() = default;
    GenericOptRect(GenericRect<C> const &a) : Base(CRect(a)) {}
    GenericOptRect(CPoint const &a, CPoint const &b) : Base(CRect(a, b)) {}
    GenericOptRect(C x0, C y0, C x1, C y1) : Base(CRect(x0, y0, x1, y1)) {}
    GenericOptRect(OptCInterval const &x_int, OptCInterval const &y_int) {
        if (x_int && y_int) {
            *this = CRect(*x_int, *y_int);
        }
        // else, stay empty.
    }
 
    template <typename InputIterator>
    static OptCRect from_range(InputIterator start, InputIterator end) {
        OptCRect result;
        for (; start != end; ++start) {
            result.expandTo(*start);
        }
        return result;
    }
 
 
    inline bool empty() const { return !*this; };
    bool intersects(CRect const &r) const { return r.intersects(*this); }
    bool contains(CRect const &r) const { return *this && (*this)->contains(r); }
 
    bool intersects(OptCRect const &r) const { return *this && (*this)->intersects(r); }
    bool contains(OptCRect const &r) const { return *this && (*this)->contains(r); }
 
    bool contains(CPoint const &p) const { return *this && (*this)->contains(p); }
 
    C area() const { return *this ? (*this)->area() : 0; }
    bool hasZeroArea() const { return !*this || (*this)->hasZeroArea(); }
    OptCRect regularized() const { return hasZeroArea() ? OptCRect() : *this; }
 
 
    void unionWith(CRect const &b) {
        if (*this) {
            (*this)->unionWith(b);
        } else {
            *this = b;
        }
    }
    void unionWith(OptCRect const &b) {
        if (b) unionWith(*b);
    }
    void intersectWith(CRect const &b) {
        if (!*this) return;
        OptCInterval x = (**this)[X] & b[X], y = (**this)[Y] & b[Y];
        if (x && y) {
            *this = CRect(*x, *y);
        } else {
            *this = {};
        }
    }
    void intersectWith(OptCRect const &b) {
        if (b) {
            intersectWith(*b);
        } else {
            *this = {};
        }
    }
    void expandTo(CPoint const &p) {
        if (*this) {
            (*this)->expandTo(p);
        } else {
            *this = CRect(p, p);
        }
    }
    
 
    GenericOptRect<C> &operator|=(OptCRect const &b) {
        unionWith(b);
        return *this;
    }
    GenericOptRect<C> &operator&=(CRect const &b) {
        intersectWith(b);
        return *this;
    }
    GenericOptRect<C> &operator&=(OptCRect const &b) {
        intersectWith(b);
        return *this;
    }
    bool operator==(OptCRect const &other) const {
        if (!*this != !other) return false;
        return *this ? **this == *other : true;
    }
    bool operator==(CRect const &other) const {
        if (!*this) return false;
        return **this == other;
    }
};
 
template <typename C>
inline void GenericRect<C>::unionWith(OptCRect const &b) { 
    if (b) {
        unionWith(*b);
    }
}
template <typename C>
inline bool GenericRect<C>::intersects(OptCRect const &r) const {
    return r && intersects(*r);
}
template <typename C>
inline bool GenericRect<C>::contains(OptCRect const &r) const {
    return !r || contains(*r);
}
 
template <typename C>
inline std::ostream &operator<<(std::ostream &out, GenericRect<C> const &r) {
    return out << "Rect " << r[X] << " x " << r[Y];
}
 
template <typename C>
inline std::ostream &operator<<(std::ostream &out, GenericOptRect<C> const &r) {
    return r ? (out << *r) : (out << "Rect (empty)");
}
 
} // namespace Geom
 
#endif // LIB2GEOM_SEEN_GENERIC_RECT_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 :