/*
interval.hh -- part of flowerlib
-
- (c) 1996--2004 Han-Wen Nienhuys
+
+ (c) 1996--2006 Han-Wen Nienhuys
*/
#ifndef INTERVAL_HH
#define INTERVAL_HH
-#include <assert.h>
+#include <math.h>
+
#include "flower-proto.hh"
-#include "real.hh"
#include "drul-array.hh"
/* A T interval. This represents the closed interval [left,right].
struct Interval_t : public Drul_array<T>
{
Drul_array<T>::elem;
+ Drul_array<T>::elem_ref;
static T infinity ();
static String T_to_string (T arg);
- T center () const
+ T center () const;
+ void translate (T t)
{
- assert (!is_empty ());
- return (elem (LEFT) + elem (RIGHT)) / T (2);
+ elem_ref (LEFT) += t;
+ elem_ref (RIGHT) += t;
}
- void translate (T t)
- {
- elem_ref (LEFT) += t;
- elem_ref (RIGHT) += t;
- }
void widen (T t)
{
elem_ref (LEFT) -= t;
- elem_ref (RIGHT) += t;
+ elem_ref (RIGHT) += t;
+ }
+
+ T distance (T t) const
+ {
+ if (t > elem (RIGHT))
+ return T (t - elem (RIGHT));
+ else if (t < elem (LEFT))
+ return T (elem (LEFT) - t);
+ else
+ return T (0);
}
-
/**
- 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)
{
- elem_ref(LEFT) = elem (LEFT) <? p;
- elem_ref(RIGHT) = elem (RIGHT) >? p;
+ elem_ref (LEFT) = min (elem (LEFT), p);
+ elem_ref (RIGHT) = max (elem (RIGHT), p);
}
T length () const;
T delta () const;
/*
TODO: strip hungarian suffix.
- */
+ */
bool is_empty () const
{
return elem (LEFT) > elem (RIGHT);
}
- bool superset (Interval_t<T> const&) const;
+ bool superset (Interval_t<T> const &) const;
Interval_t ()
{
set_empty ();
}
- Interval_t (T m, T M) : Drul_array<T> (m,M)
- {
- }
- Interval_t<T> &operator -= (T r) {
+ Interval_t (Drul_array<T> const &src)
+ : Drul_array<T> (src)
+ {
+ }
+
+ 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) {
+ Interval_t<T> &operator += (T r)
+ {
elem_ref (LEFT) += r;
- elem_ref (RIGHT) +=r;
+ elem_ref (RIGHT) += r;
return *this;
}
- Interval_t<T> &operator *= (T r) {
+ Interval_t<T> &operator *= (T r)
+ {
if (!is_empty ())
{
elem_ref (LEFT) *= r;
elem_ref (RIGHT) *= r;
if (r < T (0))
- swap();
-
+ swap ();
}
return *this;
}
}
String to_string () const;
- bool contains (T r);
+ bool contains (T r) const;
void negate ()
{
T r = -elem (LEFT);
T l = -elem (RIGHT);
elem_ref (LEFT) = l;
- elem_ref (RIGHT) =r;
+ elem_ref (RIGHT) = r;
}
void swap ()
elem_ref (LEFT) = elem (RIGHT);
elem_ref (RIGHT) = t;
}
-};
+ static int left_comparison (Interval_t<T> const &a, Interval_t<T> const &b)
+ {
+ return sign (a[LEFT] - b[RIGHT]);
+ }
+};
/**
- inclusion ordering. Crash if not comparable.
- */
+ inclusion ordering. Crash if not comparable.
+*/
template<class T>
-int Interval__compare (const Interval_t<T>&,Interval_t<T> const&);
+int Interval__compare (const Interval_t<T> &, Interval_t<T> const &);
/**
Inclusion ordering. return -2 if not comparable
- */
+*/
template<class T>
int
-_Interval__compare (const Interval_t<T>&a,Interval_t<T> const&b);
-
+_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 (elem (LEFT) + elem (RIGHT)) / T (2);
}
-// again? see flower-proto.hh
typedef Interval_t<Real> Interval;
typedef Interval_t<int> Slice; // weird name