*** empty log message ***

[lilypond.git] / flower / include / interval.hh

diff --git a/flower/include/interval.hh b/flower/include/interval.hh
index 8d4d83a5dc7381960a169cb83c971897f658f2ec..97f1b1225a598e25d1b3b96750bc099c7b7fd77c 100644 (file)
--- a/flower/include/interval.hh
+++ b/flower/include/interval.hh
@@ -1,51 +1,73 @@
 /*
   interval.hh -- part of flowerlib
   
-  (c) 1996 Han-Wen Nienhuys
+  (c) 1996--2005 Han-Wen Nienhuys
 */
 
 #ifndef INTERVAL_HH
 #define INTERVAL_HH
 
-#include <assert.h> 
 #include "flower-proto.hh"
-#include "real.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 explicitely. */
 template<class T>
-struct Interval_t : public Drul_array<T> {
+struct Interval_t : public Drul_array<T>
+{
+  Drul_array<T>::elem;
+  Drul_array<T>::elem_ref;
 
-  /* ************** */
-    
-  static T infinity () ;
-  static String T_to_str (T arg);
-  T center () {
-    assert (!empty_b ());
-    return (elem (LEFT) + elem (RIGHT)) / T (2);
-  }
+  static T infinity ();
+  static String T_to_string (T arg);
+  T center () const;
   void translate (T t)
     {
-      elem (LEFT) += t;
-      elem (RIGHT) += t;
+      elem_ref (LEFT) += t;
+      elem_ref (RIGHT) += t;
     }
+  void widen (T t)
+  {
+    elem_ref (LEFT) -= 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
     */
   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;
+  }
   T length () const;
-  void set_empty () ;
-  bool empty_b () const { return elem (LEFT) > elem (RIGHT); }
-  bool contains_b (Interval_t<T> const&) const;
-  Interval_t () {
+  T delta () const;
+  void set_empty ();
+  void set_full ();
+
+  /*
+    TODO: strip hungarian suffix.
+   */
+  bool is_empty () const
+  {
+    return elem (LEFT) > elem (RIGHT);
+  }
+  bool superset (Interval_t<T> const&) const;
+  Interval_t ()
+  {
     set_empty ();
   }
   Interval_t (T m, T M) : Drul_array<T> (m,M)
@@ -57,15 +79,15 @@ struct Interval_t : public Drul_array<T> {
   }
 
   Interval_t<T> &operator += (T r) {
-    elem (LEFT) += r;
-    elem (RIGHT) +=r;
+    elem_ref (LEFT) += r;
+    elem_ref (RIGHT) +=r;
     return *this;
   }
   Interval_t<T> &operator *= (T r) {
-    if (!empty_b ())
+    if (!is_empty ())
       {
-       elem (LEFT) *= r;
-       elem (RIGHT) *= r;
+       elem_ref (LEFT) *= r;
+       elem_ref (RIGHT) *= r;
        if (r < T (0))
          swap();
 
@@ -73,25 +95,27 @@ struct Interval_t : public Drul_array<T> {
     return *this;
   }
 
-  Real linear_combination (Real x) const {
-    return ((1.0 - x) * Real (elem (LEFT))  + (x + 1.0) * Real (elem (RIGHT))) * 0.5;
+  Real linear_combination (Real x) const
+  {
+    Drul_array<Real> da (elem (LEFT), elem (RIGHT));
+    return ::linear_combination (da, x);
   }
-  String str () const;    
+  String to_string () const;
 
-  bool elem_b (T r);
-  void negate () {
+  bool contains (T r);
+  void negate ()
+  {
     T r = -elem (LEFT);
     T l = -elem (RIGHT);
-    elem (LEFT) = l;
-    elem (RIGHT) =r;
+    elem_ref (LEFT) = l;
+    elem_ref (RIGHT) =r;
   }
-private:
 
   void swap ()
   {
     T t = elem (LEFT);
-    elem (LEFT) = elem (RIGHT);
-    elem (RIGHT) = t;
+    elem_ref (LEFT) = elem (RIGHT);
+    elem_ref (RIGHT) = t;
   }
 };
 
@@ -173,6 +197,15 @@ 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