Commit LivePathEffect branch to trunk!

(disabled extension/internal/bitmap/*.* in build.xml to fix compilation)

(bzr r3472)

1 files changed, 219 insertions, 0 deletions

diff --git a/src/2geom/interval.h b/src/2geom/interval.h
new file mode 100644
index 000000000..459f2cd49
--- /dev/null
+++ b/src/2geom/interval.h
@@ -0,0 +1,219 @@
+/*
+ * interval.h - Simple closed interval class
+ *
+ * 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 SEEN_INTERVAL_H
+#define SEEN_INTERVAL_H
+
+#include <assert.h>
+#include "coord.h"
+
+#include <boost/optional/optional.hpp>
+
+namespace Geom {
+
+//
+class Interval {
+private:
+    Coord _b[2];
+
+public:
+    //TODO: I just know this'll pop up somewhere, starting off someone's interval at 0...  I can't see how to avoid this.
+    explicit Interval() { _b[0] = _b[1] = 0; }    
+    explicit Interval(Coord u) { _b[0] = _b[1] = u; }
+    Interval(Coord u, Coord v) {
+        if(u < v) {
+            _b[0] = u; _b[1] = v;
+        } else {
+            _b[0] = v; _b[1] = u;
+        }
+    }
+
+    double operator[](unsigned i) const {
+        assert(i < 2);
+        return _b[i];
+    }
+    double& operator[](unsigned i) { return _b[i]; }  //Trust the user...
+
+    Coord min() const { return _b[0]; }
+    Coord max() const { return _b[1]; }
+    Coord extent() const { return _b[1] - _b[0]; }
+    Coord middle() const { return (_b[1] + _b[0]) * 0.5; }
+
+    bool isEmpty() const { return _b[0] == _b[1]; }
+    bool contains(Coord val) const { return _b[0] <= val && val <= _b[1]; }
+    bool contains(const Interval & val) const { return _b[0] <= val._b[0] && val._b[1] <= _b[1]; }
+    bool intersects(const Interval & val) const {
+        return contains(val._b[0]) || contains(val._b[1]) || val.contains(*this);
+    }
+
+    static Interval fromArray(const Coord* c, int n) {
+        assert(n > 0);
+        Interval result(c[0]);
+        for(int i = 1; i < n; i++) result.extendTo(c[i]);
+        return result;
+    }
+
+    bool operator==(Interval other) { return _b[0] == other._b[0] && _b[1] == other._b[1]; }
+    bool operator!=(Interval other) { return _b[0] != other._b[0] || _b[1] != other._b[1]; }
+
+    //IMPL: OffsetableConcept
+    //TODO: rename output_type to something else in the concept
+    typedef Coord output_type;
+    Interval operator+(Coord amnt) {
+        return Interval(_b[0] + amnt, _b[1] + amnt);
+    }
+    Interval operator-(Coord amnt) {
+        return Interval(_b[0] - amnt, _b[1] - amnt);
+    }
+    Interval operator+=(Coord amnt) {
+        _b[0] += amnt; _b[1] += amnt;
+        return *this;
+    }
+    Interval operator-=(Coord amnt) {
+        _b[0] -= amnt; _b[1] -= amnt;
+        return *this;
+    }
+
+    //IMPL: ScalableConcept
+    Interval operator-() const { return Interval(*this); }
+    Interval operator*(Coord s) const { return Interval(_b[0]*s, _b[1]*s); }
+    Interval operator/(Coord s) const { return Interval(_b[0]/s, _b[1]/s); }
+    Interval operator*=(Coord s) {
+        if(s < 0) {
+            Coord temp = _b[0];
+            _b[0] = _b[1]*s;
+            _b[1] = temp*s;
+        } else {
+            _b[0] *= s;
+            _b[1] *= s;
+        }
+        return *this;
+    }
+    Interval operator/=(Coord s) {
+        //TODO: what about s=0?
+        if(s < 0) {
+            Coord temp = _b[0];
+            _b[0] = _b[1]/s;
+            _b[1] = temp/s;
+        } else {
+            _b[0] /= s;
+            _b[1] /= s;
+        }
+        return *this;
+    }
+
+    //TODO: NaN handleage for the next two?
+    //TODO: Evaluate if wrap behaviour is proper.
+    //If val > max, then rather than becoming a min==max range, it 'wraps' over
+    void setMin(Coord val) {
+        if(val > _b[1]) {
+            _b[0] = _b[1];
+            _b[1] = val;
+        } else {
+            _b[0] = val;
+        }
+    }
+    //If val < min, then rather than becoming a min==max range, it 'wraps' over
+    void setMax(Coord val) {
+        if(val < _b[0]) {
+            _b[1] = _b[0];
+            _b[0] = val;
+        } else {
+            _b[1] = val;
+        }
+    }
+
+    void extendTo(Coord val) {
+       if(val < _b[0]) _b[0] = val;
+       if(val > _b[1]) _b[1] = val;  //no else, as we want to handle NaN
+    }
+
+    void expandBy(double amnt) {
+        _b[0] -= amnt;
+        _b[1] += amnt;
+    }
+
+    void unionWith(const Interval & a) {
+        if(a._b[0] < _b[0]) _b[0] = a._b[0];
+        if(a._b[1] > _b[1]) _b[1] = a._b[1];
+    }
+};
+
+//IMPL: AddableConcept
+inline Interval operator+(const Interval & a, const Interval & b) {
+    return Interval(a.min() + b.min(), a.max() + b.max());
+}
+inline Interval operator-(const Interval & a, const Interval & b) {
+    return Interval(a.min() - b.max(), a.max() - b.min());
+}
+inline Interval operator+=(Interval & a, const Interval & b) { a = a + b; return a; }
+inline Interval operator-=(Interval & a, const Interval & b) { a = a - b; return a; }
+
+//There might be impls of this based off sign checks
+inline Interval operator*(const Interval & a, const Interval & b) {
+    Interval res(a.min() * b.min());
+    res.extendTo(a.min() * b.max());
+    res.extendTo(a.max() * b.min());
+    res.extendTo(a.max() * b.max());
+    return res;
+}
+inline Interval operator*=(Interval & a, const Interval & b) { a = a * b; return a; }
+
+/* reinstate if useful (doesn't do the proper thing for 0 inclusion)
+inline Interval operator/(const Interval & a, const Interval & b) {
+    Interval res(a.min() / b.min());
+    res.extendTo(a.min() / b.max());
+    res.extendTo(a.max() / b.min());
+    res.extendTo(a.max() / b.max());
+    return res;
+}
+inline Interval operator/=(Interval & a, const Interval & b) { a = a / b; return a; }
+*/
+
+// 'union' conflicts with C keyword
+inline Interval unify(const Interval & a, const Interval & b) {
+    return Interval(std::min(a.min(), b.min()),
+                    std::max(a.max(), b.max()));
+}
+inline boost::optional<Interval> intersect(const Interval & a, const Interval & b) {
+    Coord u = std::max(a.min(), b.min()),
+          v = std::min(a.max(), b.max());
+    //technically >= might be incorrect, but singulars suck
+    return u >= v ? boost::optional<Interval>()
+                  : boost::optional<Interval>(Interval(u, v));
+}
+
+}
+#endif //SEEN_INTERVAL_H