/*
- interval.hh -- part of flowerlib
-
- (c) 1996 Han-Wen Nienhuys
+ This file is part of LilyPond, the GNU music typesetter.
+
+ Copyright (C) 1996--2015 Han-Wen Nienhuys
+
+ LilyPond is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ LilyPond is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with LilyPond. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef INTERVAL_HH
#define INTERVAL_HH
-#include <assert.h>
-#include "fproto.hh"
-#include "real.hh"
+#include <math.h>
+#include "flower-proto.hh"
+#include "std-string.hh"
+#include "drul-array.hh"
-/** a T interval. this represents the closed interval [left,right].
- No invariants. T must be a totally ordered ring (with division, anyway ..)
- At instantiation, the function infinity() has to be defined explicitely.
-
- */
+/* A T interval. This represents the closed interval [left,right].
+ No invariants. T must be a totally ordered ring (with division, anyway ..)
+ At instantiation, the function infinity () has to be defined explicitly. */
template<class T>
-struct Interval_t {
- T left, right;
-
- /* ************** */
-
- static T infinity() ;
- static String T_to_str (T arg);
-
- // ugh, egcs 1.02 ices on this
-// T center() { return (left + right) / T(2);}
- // and can't handle this either
- // anyone want to make a bug report?
- // better make one soon, egcs in rh5.1 barfs on this!
- T center() {
- T two (2);
-// return (left + right) / two;
- T result ((left + right) / two);
- return result;
+struct Interval_t : public Drul_array<T>
+{
+ using Drul_array<T>::at;
+
+ static T infinity ();
+ static string T_to_string (T arg);
+ T center () const;
+ void translate (T t)
+ {
+ at (LEFT) += t;
+ at (RIGHT) += t;
}
- void translate (T t) {
- left += t;
- right += t;
+ void widen (T t)
+ {
+ at (LEFT) -= t;
+ at (RIGHT) += t;
}
- T& idx (int j) {
- if (j==-1)
- return left;
- else if (j==1)
- return right;
+
+ T distance (T t) const
+ {
+ if (t > at (RIGHT))
+ return T (t - at (RIGHT));
+ else if (t < at (LEFT))
+ return T (at (LEFT) - t);
else
- assert (false);
- return left;
- }
- T& operator[](int j) {
- return idx (j);
- }
- T operator[](int j) const {
- return ((Interval_t<T> *)this)->idx (j);
+ return T (0);
}
- T &max() { return right;}
- T max() const { return right;}
- T min() const{ return left; }
- T &min(){ return left; }
/**
- PRE
- *this and h are comparable
- */
+ PRE
+ *this and h are comparable
+ */
void unite (Interval_t<T> h);
void intersect (Interval_t<T> h);
+ void add_point (T p)
+ {
+ at (LEFT) = min (at (LEFT), p);
+ at (RIGHT) = max (at (RIGHT), p);
+ }
+ T length () const;
+
+ // Returns RIGHT - LEFT, even if the interval is empty.
+ T delta () const;
+ void set_empty ();
+ void set_full ();
- T length() const;
- void set_empty() ;
- bool empty_b() const { return left > right; }
- bool contains_b (Interval_t<T> const&) const;
- Interval_t() {
- set_empty();
+ void unite_disjoint (Interval_t<T> h, T padding, Direction d);
+ Interval_t<T> union_disjoint (Interval_t<T> h, T padding, Direction d) const;
+
+ bool is_empty () const
+ {
+ return at (LEFT) > at (RIGHT);
+ }
+ bool superset (Interval_t<T> const &) const;
+ Interval_t ()
+ {
+ set_empty ();
}
- Interval_t (T m, T M) {
- left =m;
- right = M;
+ Interval_t (Drul_array<T> const &src)
+ : Drul_array<T> (src)
+ {
}
- Interval_t<T> &operator -= (T r) {
+
+ Interval_t (T m, T M) : Drul_array<T> (m, M)
+ {
+ }
+ Interval_t<T> &operator -= (T r)
+ {
*this += -r;
return *this;
}
- Interval_t<T> &operator += (T r) {
- left += r;
- right +=r;
+ Interval_t<T> &operator += (T r)
+ {
+ at (LEFT) += r;
+ at (RIGHT) += r;
return *this;
}
- Interval_t<T> &operator *=(T r) {
- left *= r;
- right *= r;
- if (r < T(0)) {
- T t = left;
- left = right;
- right = t;
- }
+ Interval_t<T> &operator *= (T r)
+ {
+ if (!is_empty ())
+ {
+ at (LEFT) *= r;
+ at (RIGHT) *= r;
+ if (r < T (0))
+ swap ();
+ }
return *this;
}
- String str() const;
- void print () const;
- bool elem_b (T r);
- void negate () {
- T r = -left;
- T l = -right;
- left = l;
- right =r;
+
+ Real linear_combination (Real x) const;
+ string to_string () const;
+
+ bool contains (T r) const;
+ void negate ()
+ {
+ T r = -at (LEFT);
+ T l = -at (RIGHT);
+ at (LEFT) = l;
+ at (RIGHT) = r;
+ }
+
+ void swap ()
+ {
+ T t = at (LEFT);
+ at (LEFT) = at (RIGHT);
+ at (RIGHT) = t;
+ }
+
+ static bool left_less (Interval_t<T> const &a, Interval_t<T> const &b)
+ {
+ return a[LEFT] < b[LEFT];
}
};
+/**
+ inclusion ordering. Crash if not comparable.
+*/
+template<class T>
+int Interval__compare (const Interval_t<T> &, Interval_t<T> const &);
/**
- inclusion ordering. Crash if not comparable.
- */
+ Inclusion ordering. return -2 if not comparable
+*/
template<class T>
-int Interval__compare (const Interval_t<T>&,Interval_t<T> const&);
+int
+_Interval__compare (const Interval_t<T> &a, Interval_t<T> const &b);
/*
INLINE
- */
+*/
#include "compare.hh"
-TEMPLATE_INSTANTIATE_COMPARE(Interval_t<T>&, Interval__compare, template<class T>);
-
+TEMPLATE_INSTANTIATE_COMPARE (Interval_t<T> &, Interval__compare, template<class T>);
template<class T>
inline Interval_t<T>
-intersection (Interval_t<T> a, Interval_t<T> const&b)
+intersection (Interval_t<T> a, Interval_t<T> const &b)
{
a.intersect (b);
return a;
-
}
template<class T>
inline
-Interval_t<T> operator +(T a,Interval_t<T> i)
+Interval_t<T> operator + (T a, Interval_t<T> i)
{
i += a;
return i;
template<class T>
inline
-Interval_t<T> operator - (T a,Interval_t<T> i)
+Interval_t<T> operator - (T a, Interval_t<T> i)
{
i.negate ();
i += a;
template<class T>
inline
-Interval_t<T> operator +(Interval_t<T> i,T a){
- return a+i;
+Interval_t<T> operator + (Interval_t<T> i, T a)
+{
+ return a + i;
}
template<class T>
inline
-Interval_t<T> operator *(T a,Interval_t<T> i)
+Interval_t<T> operator * (T a, Interval_t<T> i)
{
i *= a;
return i;
template<class T>
inline
-Interval_t<T> operator *(Interval_t<T> i,T a){
- return a*i;
+Interval_t<T> operator * (Interval_t<T> i, T a)
+{
+ return a * i;
+}
+
+template<class T>
+inline T
+Interval_t<T>::center () const
+{
+ assert (!is_empty ());
+ return (at (LEFT) + at (RIGHT)) / T (2);
}
-// again? see fproto.hh
typedef Interval_t<Real> Interval;
-typedef Interval_t<int> Slice;
+typedef Interval_t<int> Slice; // weird name
#endif // INTERVAL_HH