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diff --git a/include/2geom/generic-rect.h b/include/2geom/generic-rect.h new file mode 100644 index 0000000..4524d43 --- /dev/null +++ b/include/2geom/generic-rect.h @@ -0,0 +1,547 @@ +/** + * \file + * \brief Axis-aligned rectangle + *//* + * 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; + +/** + * @brief Axis aligned, non-empty, generic rectangle. + * @ingroup Primitives + */ +template <typename C> +class GenericRect + : CoordTraits<C>::RectOps +{ + typedef typename CoordTraits<C>::IntervalType CInterval; + typedef typename CoordTraits<C>::PointType CPoint; + typedef typename CoordTraits<C>::RectType CRect; + typedef typename CoordTraits<C>::OptRectType OptCRect; +protected: + CInterval f[2]; +public: + typedef CInterval D1Value; + typedef CInterval &D1Reference; + typedef CInterval const &D1ConstReference; + + /// @name Create rectangles. + /// @{ + /** @brief Create a rectangle that contains only the point at (0,0). */ + GenericRect() { f[X] = f[Y] = CInterval(); } + /** @brief Create a rectangle from X and Y intervals. */ + GenericRect(CInterval const &a, CInterval const &b) { + f[X] = a; + f[Y] = b; + } + /** @brief Create a rectangle from two points. */ + GenericRect(CPoint const &a, CPoint const &b) { + f[X] = CInterval(a[X], b[X]); + f[Y] = CInterval(a[Y], b[Y]); + } + /** @brief Create rectangle from coordinates of two points. */ + GenericRect(C x0, C y0, C x1, C y1) { + f[X] = CInterval(x0, x1); + f[Y] = CInterval(y0, y1); + } + /** @brief Create a rectangle from a range of points. + * The resulting rectangle will contain all points from the range. + * The return type of iterators must be convertible to Point. + * The range must not be empty. For possibly empty ranges, see OptRect. + * @param start Beginning of the range + * @param end End of the range + * @return Rectangle that contains all points from [start, end). */ + template <typename InputIterator> + static CRect from_range(InputIterator start, InputIterator end) { + assert(start != end); + CPoint p1 = *start++; + CRect result(p1, p1); + for (; start != end; ++start) { + result.expandTo(*start); + } + return result; + } + /** @brief Create a rectangle from a C-style array of points it should contain. */ + static CRect from_array(CPoint const *c, unsigned n) { + CRect result = GenericRect<C>::from_range(c, c+n); + return result; + } + /** @brief Create rectangle from origin and dimensions. */ + static CRect from_xywh(C x, C y, C w, C h) { + CPoint xy(x, y); + CPoint wh(w, h); + CRect result(xy, xy + wh); + return result; + } + /** @brief Create rectangle from origin and dimensions. */ + static CRect from_xywh(CPoint const &xy, CPoint const &wh) { + CRect result(xy, xy + wh); + return result; + } + /// Create infinite rectangle. + static CRect infinite() { + CPoint p0(std::numeric_limits<C>::min(), std::numeric_limits<C>::min()); + CPoint p1(std::numeric_limits<C>::max(), std::numeric_limits<C>::max()); + CRect result(p0, p1); + return result; + } + /// @} + + /// @name Inspect dimensions. + /// @{ + 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]; } + + /** @brief Get the corner of the rectangle with smallest coordinate values. + * In 2Geom standard coordinate system, this means upper left. */ + CPoint min() const { CPoint p(f[X].min(), f[Y].min()); return p; } + /** @brief Get the corner of the rectangle with largest coordinate values. + * In 2Geom standard coordinate system, this means lower right. */ + CPoint max() const { CPoint p(f[X].max(), f[Y].max()); return p; } + /** @brief Return the n-th corner of the rectangle. + * Returns corners in the direction of growing angles, starting from + * the one given by min(). For the standard coordinate system used + * in 2Geom (+Y downwards), this means clockwise starting from + * the upper left. */ + 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()); + } + } + + //We should probably remove these - they're coord sys gnostic + /** @brief Return top coordinate of the rectangle (+Y is downwards). */ + C top() const { return f[Y].min(); } + /** @brief Return bottom coordinate of the rectangle (+Y is downwards). */ + C bottom() const { return f[Y].max(); } + /** @brief Return leftmost coordinate of the rectangle (+X is to the right). */ + C left() const { return f[X].min(); } + /** @brief Return rightmost coordinate of the rectangle (+X is to the right). */ + C right() const { return f[X].max(); } + + /** @brief Get the horizontal extent of the rectangle. */ + C width() const { return f[X].extent(); } + /** @brief Get the vertical extent of the rectangle. */ + C height() const { return f[Y].extent(); } + /** @brief Get the ratio of width to height of the rectangle. */ + Coord aspectRatio() const { return Coord(width()) / Coord(height()); } + + /** @brief Get rectangle's width and height as a point. + * @return Point with X coordinate corresponding to the width and the Y coordinate + * corresponding to the height of the rectangle. */ + CPoint dimensions() const { return CPoint(f[X].extent(), f[Y].extent()); } + /** @brief Get the point in the geometric center of the rectangle. */ + CPoint midpoint() const { return CPoint(f[X].middle(), f[Y].middle()); } + + /** @brief Compute rectangle's area. */ + C area() const { return f[X].extent() * f[Y].extent(); } + /** @brief Check whether the rectangle has zero area. */ + bool hasZeroArea() const { return f[X].isSingular() || f[Y].isSingular(); } + + /** @brief Get the larger extent (width or height) of the rectangle. */ + C maxExtent() const { return std::max(f[X].extent(), f[Y].extent()); } + /** @brief Get the smaller extent (width or height) of the rectangle. */ + C minExtent() const { return std::min(f[X].extent(), f[Y].extent()); } + + /** @brief Get rectangle's distance SQUARED away from the given point **/ + C distanceSq(const CPoint pt) const { + auto v = clamp(pt) - pt; + return v.x() * v.x() + v.y() * v.y(); + } + + /** @brief Clamp point to the rectangle. */ + CPoint clamp(CPoint const &p) const { + CPoint result(f[X].clamp(p[X]), f[Y].clamp(p[Y])); + return result; + } + /** @brief Get the nearest point on the edge of the rectangle. */ + CPoint nearestEdgePoint(CPoint const &p) const { + CPoint result = p; + if (!contains(p)) { + result = clamp(p); + } else { + 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; + } + /// @} + + /// @name Test other rectangles and points for inclusion. + /// @{ + /** @brief Check whether the rectangles have any common points. */ + bool intersects(GenericRect<C> const &r) const { + return f[X].intersects(r[X]) && f[Y].intersects(r[Y]); + } + /** @brief Check whether the rectangle includes all points in the given rectangle. */ + bool contains(GenericRect<C> const &r) const { + return f[X].contains(r[X]) && f[Y].contains(r[Y]); + } + + /** @brief Check whether the rectangles have any common points. + * Empty rectangles will not intersect with any other rectangle. */ + inline bool intersects(OptCRect const &r) const; + /** @brief Check whether the rectangle includes all points in the given rectangle. + * Empty rectangles will be contained in any non-empty rectangle. */ + inline bool contains(OptCRect const &r) const; + + /** @brief Check whether the given point is within the rectangle. */ + bool contains(CPoint const &p) const { + return f[X].contains(p[X]) && f[Y].contains(p[Y]); + } + /// @} + + /// @name Modify the rectangle. + /// @{ + /** @brief Set the minimum X coordinate of the rectangle. */ + void setLeft(C val) { + f[X].setMin(val); + } + /** @brief Set the maximum X coordinate of the rectangle. */ + void setRight(C val) { + f[X].setMax(val); + } + /** @brief Set the minimum Y coordinate of the rectangle. */ + void setTop(C val) { + f[Y].setMin(val); + } + /** @brief Set the maximum Y coordinate of the rectangle. */ + void setBottom(C val) { + f[Y].setMax(val); + } + /** @brief Set the upper left point of the rectangle. */ + void setMin(CPoint const &p) { + f[X].setMin(p[X]); + f[Y].setMin(p[Y]); + } + /** @brief Set the lower right point of the rectangle. */ + void setMax(CPoint const &p) { + f[X].setMax(p[X]); + f[Y].setMax(p[Y]); + } + /** @brief Enlarge the rectangle to contain the given point. */ + void expandTo(CPoint const &p) { + f[X].expandTo(p[X]); f[Y].expandTo(p[Y]); + } + /** @brief Enlarge the rectangle to contain the argument. */ + void unionWith(CRect const &b) { + f[X].unionWith(b[X]); f[Y].unionWith(b[Y]); + } + /** @brief Enlarge the rectangle to contain the argument. + * Unioning with an empty rectangle results in no changes. */ + void unionWith(OptCRect const &b); + + /** @brief Expand the rectangle in both directions by the specified amount. + * Note that this is different from scaling. Negative values will shrink the + * rectangle. If <code>-amount</code> is larger than + * half of the width, the X interval will contain only the X coordinate + * of the midpoint; same for height. */ + void expandBy(C amount) { + expandBy(amount, amount); + } + /** @brief Expand the rectangle in both directions. + * Note that this is different from scaling. Negative values will shrink the + * rectangle. If <code>-x</code> is larger than + * half of the width, the X interval will contain only the X coordinate + * of the midpoint; same for height. */ + void expandBy(C x, C y) { + f[X].expandBy(x); f[Y].expandBy(y); + } + /** @brief Expand the rectangle by the coordinates of the given point. + * This will expand the width by the X coordinate of the point in both directions + * and the height by Y coordinate of the point. Negative coordinate values will + * shrink the rectangle. If <code>-p[X]</code> is larger than half of the width, + * the X interval will contain only the X coordinate of the midpoint; + * same for height. */ + void expandBy(CPoint const &p) { + expandBy(p[X], p[Y]); + } + /// @} + + /// @name Operators + /// @{ + /** @brief Offset the rectangle by a vector. */ + GenericRect<C> &operator+=(CPoint const &p) { + f[X] += p[X]; + f[Y] += p[Y]; + return *this; + } + /** @brief Offset the rectangle by the negation of a vector. */ + GenericRect<C> &operator-=(CPoint const &p) { + f[X] -= p[X]; + f[Y] -= p[Y]; + return *this; + } + /** @brief Union two rectangles. */ + GenericRect<C> &operator|=(CRect const &o) { + unionWith(o); + return *this; + } + GenericRect<C> &operator|=(OptCRect const &o) { + unionWith(o); + return *this; + } + /** @brief Test for equality of rectangles. */ + bool operator==(CRect const &o) const { return f[X] == o[X] && f[Y] == o[Y]; } + /// @} +}; + +/** + * @brief Axis-aligned generic rectangle that can be empty. + * @ingroup Primitives + */ +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 + > > > > > +{ + typedef typename CoordTraits<C>::IntervalType CInterval; + typedef typename CoordTraits<C>::OptIntervalType OptCInterval; + typedef typename CoordTraits<C>::PointType CPoint; + typedef typename CoordTraits<C>::RectType CRect; + typedef typename CoordTraits<C>::OptRectType OptCRect; + typedef std::optional<CRect> Base; +public: + typedef CInterval D1Value; + typedef CInterval &D1Reference; + typedef CInterval const &D1ConstReference; + + /// @name Create potentially empty rectangles. + /// @{ + GenericOptRect() : Base() {} + 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)) {} + /// Creates an empty OptRect when one of the argument intervals is empty. + GenericOptRect(OptCInterval const &x_int, OptCInterval const &y_int) { + if (x_int && y_int) { + *this = CRect(*x_int, *y_int); + } + // else, stay empty. + } + + /** @brief Create a rectangle from a range of points. + * The resulting rectangle will contain all points from the range. + * If the range contains no points, the result will be an empty rectangle. + * The return type of iterators must be convertible to the corresponding + * point type (Point or IntPoint). + * @param start Beginning of the range + * @param end End of the range + * @return Rectangle that contains all points from [start, end). */ + template <typename InputIterator> + static OptCRect from_range(InputIterator start, InputIterator end) { + OptCRect result; + for (; start != end; ++start) { + result.expandTo(*start); + } + return result; + } + /// @} + + /// @name Check other rectangles and points for inclusion. + /// @{ + /** @brief Check for emptiness. */ + inline bool empty() const { return !*this; }; + /** @brief Check whether the rectangles have any common points. + * Empty rectangles will not intersect with any other rectangle. */ + bool intersects(CRect const &r) const { return r.intersects(*this); } + /** @brief Check whether the rectangle includes all points in the given rectangle. + * Empty rectangles will be contained in any non-empty rectangle. */ + bool contains(CRect const &r) const { return *this && (*this)->contains(r); } + + /** @brief Check whether the rectangles have any common points. + * Empty rectangles will not intersect with any other rectangle. + * Two empty rectangles will not intersect each other. */ + bool intersects(OptCRect const &r) const { return *this && (*this)->intersects(r); } + /** @brief Check whether the rectangle includes all points in the given rectangle. + * Empty rectangles will be contained in any non-empty rectangle. + * An empty rectangle will not contain other empty rectangles. */ + bool contains(OptCRect const &r) const { return *this && (*this)->contains(r); } + + /** @brief Check whether the given point is within the rectangle. + * An empty rectangle will not contain any points. */ + bool contains(CPoint const &p) const { return *this && (*this)->contains(p); } + /// @} + + /** @brief Returns an empty optional (testing false) if the rectangle has zero area. */ + OptCRect regularized() const { + return *this && !(*this)->hasZeroArea() ? *this : OptCRect(); + } + + /// @name Modify the potentially empty rectangle. + /// @{ + /** @brief Enlarge the rectangle to contain the argument. + * If this rectangle is empty, after callng this method it will + * be equal to the argument. */ + void unionWith(CRect const &b) { + if (*this) { + (*this)->unionWith(b); + } else { + *this = b; + } + } + /** @brief Enlarge the rectangle to contain the argument. + * Unioning with an empty rectangle results in no changes. + * If this rectangle is empty, after calling this method it will + * be equal to the argument. */ + void unionWith(OptCRect const &b) { + if (b) unionWith(*b); + } + /** @brief Leave only the area overlapping with the argument. + * If the rectangles do not have any points in common, after calling + * this method the rectangle will be empty. */ + 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 { + *(static_cast<Base*>(this)) = std::nullopt; + } + } + /** @brief Leave only the area overlapping with the argument. + * If the argument is empty or the rectangles do not have any points + * in common, after calling this method the rectangle will be empty. */ + void intersectWith(OptCRect const &b) { + if (b) { + intersectWith(*b); + } else { + *(static_cast<Base*>(this)) = std::nullopt; + } + } + /** @brief Create or enlarge the rectangle to contain the given point. + * If the rectangle is empty, after calling this method it will be non-empty + * and it will contain only the given point. */ + void expandTo(CPoint const &p) { + if (*this) { + (*this)->expandTo(p); + } else { + *this = CRect(p, p); + } + } + /// @} + + /// @name Operators + /// @{ + /** @brief Union with @a b */ + GenericOptRect<C> &operator|=(OptCRect const &b) { + unionWith(b); + return *this; + } + /** @brief Intersect with @a b */ + GenericOptRect<C> &operator&=(CRect const &b) { + intersectWith(b); + return *this; + } + /** @brief Intersect with @a b */ + GenericOptRect<C> &operator&=(OptCRect const &b) { + intersectWith(b); + return *this; + } + /** @brief Test for equality. + * All empty rectangles are equal. */ + 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) { + out << "Rect " << r[X] << " x " << r[Y]; + return out; +} + +} // end namespace Geom + +#endif // LIB2GEOM_SEEN_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 : |