--- deliantra/server/include/util.h	2007/04/21 22:57:16	1.41
+++ deliantra/server/include/util.h	2007/07/01 05:00:18	1.51
@@ -1,14 +1,49 @@
+/*
+ * This file is part of Crossfire TRT, the Roguelike Realtime MORPG.
+ * 
+ * Copyright (©) 2005,2006,2007 Marc Alexander Lehmann / Robin Redeker / the Crossfire TRT team
+ * 
+ * Crossfire TRT 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.
+ * 
+ * This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
+ * 
+ * The authors can be reached via e-mail to <crossfire@schmorp.de>
+ */
+
 #ifndef UTIL_H__
 #define UTIL_H__
 
 //#define PREFER_MALLOC
 
 #if __GNUC__ >= 3
-# define is_constant(c) __builtin_constant_p (c)
+# define is_constant(c)             __builtin_constant_p (c)
+# define expect(expr,value)         __builtin_expect ((expr),(value))
+# define prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
 #else
-# define is_constant(c) 0
+# define is_constant(c)             0
+# define expect(expr,value)         (expr)
+# define prefetch(addr,rw,locality)
+#endif
+
+#if __GNUC__ < 4 || (__GNUC__ == 4 || __GNUC_MINOR__ < 4)
+# define decltype(x) typeof(x)
 #endif
 
+// put into ifs if you are very sure that the expression
+// is mostly true or mosty false. note that these return
+// booleans, not the expression.
+#define expect_false(expr) expect ((expr) != 0, 0)
+#define expect_true(expr)  expect ((expr) != 0, 1)
+
 #include <cstddef>
 #include <cmath>
 #include <new>
@@ -19,15 +54,15 @@
 #include <shstr.h>
 #include <traits.h>
 
-// use a gcc extension for auto declarations until ISO C++ sanctifies them
-#define auto(var,expr) typeof(expr) var = (expr)
+// use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever)
+#define auto(var,expr) decltype(expr) var = (expr)
 
 // very ugly macro that basicaly declares and initialises a variable
 // that is in scope for the next statement only
 // works only for stuff that can be assigned 0 and converts to false
 // (note: works great for pointers)
 // most ugly macro I ever wrote
-#define declvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1)
+#define statementvar(type, name, value) if (type name = 0) { } else if (((name) = (value)), 1)
 
 // in range including end
 #define IN_RANGE_INC(val,beg,end) \
@@ -47,6 +82,13 @@
 
 template<typename T, typename U> static inline void swap (T& a, U& b) { T t=a; a=(T)b; b=(U)t; }
 
+template<typename T>
+static inline T
+lerp (T val, T min_in, T max_in, T min_out, T max_out)
+{
+  return (val - min_in) * (max_out - min_out) / (max_in - min_in) + min_out;
+}
+
 // lots of stuff taken from FXT
 
 /* Rotate right. This is used in various places for checksumming */
@@ -264,18 +306,18 @@
   uint32_t next ();
 
   // uniform distribution
-  uint32_t operator ()(uint32_t r_max)
+  uint32_t operator ()(uint32_t num)
   {
-    return is_constant (r_max)
-             ? (next () * (uint64_t)r_max) >> 32U
-             : get_range (r_max);
+    return is_constant (num)
+             ? (next () * (uint64_t)num) >> 32U
+             : get_range (num);
   }
 
   // return a number within (min .. max)
   int operator () (int r_min, int r_max)
   {
-    return is_constant (r_min) && is_constant (r_max)
-              ? r_min + operator ()(max (r_max - r_min + 1, 1))
+    return is_constant (r_min) && is_constant (r_max) && r_min <= r_max
+              ? r_min + operator ()(r_max - r_min + 1)
               : get_range (r_min, r_max);
   }
 
@@ -364,6 +406,10 @@
   }
 };
 
+// Mostly the same as std::vector, but insert/erase can reorder
+// the elements, making insret/remove O(1) instead of O(n).
+//
+// NOTE: only some forms of erase/insert are available
 template<class T>
 struct unordered_vector : std::vector<T, slice_allocator<T> >
 {
@@ -383,14 +429,41 @@
   }
 };
 
-template<class T, int T::* index>
+// This container blends advantages of linked lists
+// (efficiency) with vectors (random access) by
+// by using an unordered vector and storing the vector
+// index inside the object.
+//
+// + memory-efficient on most 64 bit archs
+// + O(1) insert/remove
+// + free unique (but varying) id for inserted objects
+// + cache-friendly iteration
+// - only works for pointers to structs
+//
+// NOTE: only some forms of erase/insert are available
+typedef int object_vector_index;
+
+template<class T, object_vector_index T::*indexmember>
 struct object_vector : std::vector<T *, slice_allocator<T *> >
 {
+  typedef typename object_vector::iterator iterator;
+
+  bool contains (const T *obj) const
+  {
+    return obj->*indexmember;
+  }
+
+  iterator find (const T *obj)
+  {
+    return obj->*indexmember
+      ? this->begin () + obj->*indexmember - 1
+      : this->end ();
+  }
+
   void insert (T *obj)
   {
-    assert (!(obj->*index));
     push_back (obj);
-    obj->*index = this->size ();
+    obj->*indexmember = this->size ();
   }
 
   void insert (T &obj)
@@ -400,14 +473,13 @@
 
   void erase (T *obj)
   {
-    assert (obj->*index);
-    unsigned int pos = obj->*index;
-    obj->*index = 0;
+    unsigned int pos = obj->*indexmember;
+    obj->*indexmember = 0;
 
     if (pos < this->size ())
       {
         (*this)[pos - 1] = (*this)[this->size () - 1];
-        (*this)[pos - 1]->*index = pos;
+        (*this)[pos - 1]->*indexmember = pos;
       }
 
     this->pop_back ();
@@ -415,7 +487,7 @@
 
   void erase (T &obj)
   {
-    errase (&obj);
+    erase (&obj);
   }
 };
 
@@ -436,5 +508,8 @@
 
 int similar_direction (int a, int b);
 
+// like printf, but returns a std::string
+const std::string format (const char *format, ...);
+
 #endif