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-rw-r--r-- | include/2geom/rect.h | 263 |
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diff --git a/include/2geom/rect.h b/include/2geom/rect.h new file mode 100644 index 0000000..5edfc95 --- /dev/null +++ b/include/2geom/rect.h @@ -0,0 +1,263 @@ +/** + * \file + * \brief Axis-aligned rectangle + *//* + * Authors: + * Michael Sloan <mgsloan@gmail.com> + * Krzysztof KosiĆski <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_RECT_H +#define LIB2GEOM_SEEN_RECT_H + +#include <2geom/affine.h> +#include <2geom/interval.h> +#include <2geom/int-rect.h> + +namespace Geom { + +/** Values for the <align> parameter of preserveAspectRatio. + * See: http://www.w3.org/TR/SVG/coords.html#PreserveAspectRatioAttribute */ +enum Align { + ALIGN_NONE, + ALIGN_XMIN_YMIN, + ALIGN_XMID_YMIN, + ALIGN_XMAX_YMIN, + ALIGN_XMIN_YMID, + ALIGN_XMID_YMID, + ALIGN_XMAX_YMID, + ALIGN_XMIN_YMAX, + ALIGN_XMID_YMAX, + ALIGN_XMAX_YMAX +}; + +/** Values for the <meetOrSlice> parameter of preserveAspectRatio. + * See: http://www.w3.org/TR/SVG/coords.html#PreserveAspectRatioAttribute */ +enum Expansion { + EXPANSION_MEET, + EXPANSION_SLICE +}; + +/// Convert an align specification to coordinate fractions. +Point align_factors(Align align); + +/** @brief Structure that specifies placement of within a viewport. + * Use this to create transformations that preserve aspect. */ +struct Aspect { + Align align; + Expansion expansion; + bool deferred; ///< for SVG compatibility + + Aspect(Align a = ALIGN_NONE, Expansion ex = EXPANSION_MEET) + : align(a), expansion(ex), deferred(false) + {} +}; + +/** + * @brief Axis aligned, non-empty rectangle. + * @ingroup Primitives + */ +class Rect + : public GenericRect<Coord> +{ + typedef GenericRect<Coord> Base; +public: + /// @name Create rectangles. + /// @{ + /** @brief Create a rectangle that contains only the point at (0,0). */ + Rect() {} + /** @brief Create a rectangle from X and Y intervals. */ + Rect(Interval const &a, Interval const &b) : Base(a,b) {} + /** @brief Create a rectangle from two points. */ + Rect(Point const &a, Point const &b) : Base(a,b) {} + Rect(Coord x0, Coord y0, Coord x1, Coord y1) : Base(x0, y0, x1, y1) {} + Rect(Base const &b) : Base(b) {} + Rect(IntRect const &ir) : Base(ir.min(), ir.max()) {} + /// @} + + /// @name Inspect dimensions. + /// @{ + /** @brief Check whether the rectangle has zero area up to specified tolerance. + * @param eps Maximum value of the area to consider empty + * @return True if rectangle has an area smaller than tolerance, false otherwise */ + bool hasZeroArea(Coord eps = EPSILON) const { return (area() <= eps); } + /// Check whether the rectangle has finite area + bool isFinite() const { return (*this)[X].isFinite() && (*this)[Y].isFinite(); } + /// Calculate the diameter of the smallest circle that would contain the rectangle. + Coord diameter() const { return distance(corner(0), corner(2)); } + /// @} + + /// @name Test other rectangles and points for inclusion. + /// @{ + /** @brief Check whether the interiors of the rectangles have any common points. */ + bool interiorIntersects(Rect const &r) const { + return f[X].interiorIntersects(r[X]) && f[Y].interiorIntersects(r[Y]); + } + /** @brief Check whether the interior includes the given point. */ + bool interiorContains(Point const &p) const { + return f[X].interiorContains(p[X]) && f[Y].interiorContains(p[Y]); + } + /** @brief Check whether the interior includes all points in the given rectangle. + * Interior of the rectangle is the entire rectangle without its borders. */ + bool interiorContains(Rect const &r) const { + return f[X].interiorContains(r[X]) && f[Y].interiorContains(r[Y]); + } + inline bool interiorContains(OptRect const &r) const; + /// @} + + /// @name Rounding to integer coordinates + /// @{ + /** @brief Return the smallest integer rectangle which contains this one. */ + IntRect roundOutwards() const { + IntRect ir(f[X].roundOutwards(), f[Y].roundOutwards()); + return ir; + } + /** @brief Return the largest integer rectangle which is contained in this one. */ + OptIntRect roundInwards() const { + OptIntRect oir(f[X].roundInwards(), f[Y].roundInwards()); + return oir; + } + /// @} + + /// @name SVG viewbox functionality. + /// @{ + /** @brief Transform contents to viewport. + * Computes an affine that transforms the contents of this rectangle + * to the specified viewport. The aspect parameter specifies how to + * to the transformation (whether the aspect ratio of content + * should be kept and where it should be placed in the viewport). */ + Affine transformTo(Rect const &viewport, Aspect const &aspect = Aspect()) const; + /// @} + + /// @name Operators + /// @{ + Rect &operator*=(Affine const &m); + bool operator==(IntRect const &ir) const { + return f[X] == ir[X] && f[Y] == ir[Y]; + } + bool operator==(Rect const &other) const { + return Base::operator==(other); + } + /// @} +}; + +/** + * @brief Axis-aligned rectangle that can be empty. + * @ingroup Primitives + */ +class OptRect + : public GenericOptRect<Coord> +{ + typedef GenericOptRect<Coord> Base; +public: + OptRect() : Base() {} + OptRect(Rect const &a) : Base(a) {} + OptRect(Point const &a, Point const &b) : Base(a, b) {} + OptRect(Coord x0, Coord y0, Coord x1, Coord y1) : Base(x0, y0, x1, y1) {} + OptRect(OptInterval const &x_int, OptInterval const &y_int) : Base(x_int, y_int) {} + OptRect(Base const &b) : Base(b) {} + + OptRect(IntRect const &r) : Base(Rect(r)) {} + OptRect(OptIntRect const &r) : Base() { + if (r) *this = Rect(*r); + } + + Affine transformTo(Rect const &viewport, Aspect const &aspect = Aspect()) { + Affine ret = Affine::identity(); + if (empty()) return ret; + ret = (*this)->transformTo(viewport, aspect); + return ret; + } + + bool operator==(OptRect const &other) const { + return Base::operator==(other); + } + bool operator==(Rect const &other) const { + return Base::operator==(other); + } +}; + +Coord distanceSq(Point const &p, Rect const &rect); +Coord distance(Point const &p, Rect const &rect); +/// Minimum square of distance to rectangle, or infinity if empty. +Coord distanceSq(Point const &p, OptRect const &rect); +/// Minimum distance to rectangle, or infinity if empty. +Coord distance(Point const &p, OptRect const &rect); + +inline bool Rect::interiorContains(OptRect const &r) const { + return !r || interiorContains(static_cast<Rect const &>(*r)); +} + +// the functions below do not work when defined generically +inline OptRect operator&(Rect const &a, Rect const &b) { + OptRect ret(a); + ret.intersectWith(b); + return ret; +} +inline OptRect intersect(Rect const &a, Rect const &b) { + return a & b; +} +inline OptRect intersect(OptRect const &a, OptRect const &b) { + return a & b; +} +inline Rect unify(Rect const &a, Rect const &b) { + return a | b; +} +inline OptRect unify(OptRect const &a, OptRect const &b) { + return a | b; +} + +/** @brief Union a list of rectangles + * @deprecated Use OptRect::from_range instead */ +inline Rect union_list(std::vector<Rect> const &r) { + if(r.empty()) return Rect(Interval(0,0), Interval(0,0)); + Rect ret = r[0]; + for(unsigned i = 1; i < r.size(); i++) + ret.unionWith(r[i]); + return ret; +} + +} // 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 : |