--- deliantra/server/include/util.h	2008/05/03 11:14:50	1.73
+++ deliantra/server/include/util.h	2008/12/19 22:47:29	1.79
@@ -1,7 +1,7 @@
 /*
  * This file is part of Deliantra, the Roguelike Realtime MMORPG.
  * 
- * Copyright (©) 2005,2006,2007 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
+ * Copyright (©) 2005,2006,2007,2008 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
  * 
  * Deliantra is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -98,16 +98,54 @@
 template<typename T, typename U> static inline T max (T a, U b) { return (U)a > b ? (U)a : b; }
 template<typename T, typename U, typename V> static inline T clamp (T v, U a, V b) { return v < (T)a ? (T)a : v >(T)b ? (T)b : v; }
 
+template<typename T> static inline void min_it (T &v, T m) { v = min (v, m); }
+template<typename T> static inline void max_it (T &v, T m) { v = max (v, m); }
+template<typename T> static inline void clamp_it (T &v, T a, T b) { v = clamp (v, a, b); }
+
 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, typename U, typename V> static inline T min (T a, U b, V c) { return min (a, min (b, c)); }
 template<typename T, typename U, typename V> static inline T max (T a, U b, V c) { return max (a, max (b, c)); }
 
+// sign returns -1 or +1
+template<typename T>
+static inline T sign (T v) { return v < 0 ? -1 : +1; }
+// relies on 2c representation
+template<>
+inline sint8 sign (sint8 v) { return 1 - (sint8 (uint8 (v) >> 7) * 2); }
+
+// sign0 returns -1, 0 or +1
+template<typename T>
+static inline T sign0 (T v) { return v ? sign (v) : 0; }
+
+// div, with correct rounding (< 0.5 downwards, >=0.5 upwards)
+template<typename T> static inline T div    (T val, T div) { return (val + div / 2) / div; }
+// div, round-up
+template<typename T> static inline T div_ru (T val, T div) { return (val + div - 1) / div; }
+// div, round-down
+template<typename T> static inline T div_rd (T val, T div) { return (val          ) / div; }
+
 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;
+  return min_out + div   <T> ((val - min_in) * (max_out - min_out), max_in  - min_in);
+}
+
+// lerp, round-down
+template<typename T>
+static inline T
+lerp_rd (T val, T min_in, T max_in, T min_out, T max_out)
+{
+  return min_out + div_rd<T> ((val - min_in) * (max_out - min_out), max_in  - min_in);
+}
+
+// lerp, round-up
+template<typename T>
+static inline T
+lerp_ru (T val, T min_in, T max_in, T min_out, T max_out)
+{
+  return min_out + div_ru<T> ((val - min_in) * (max_out - min_out), max_in  - min_in);
 }
 
 // lots of stuff taken from FXT
@@ -367,7 +405,7 @@
   void seed (uint32_t seed);
   uint32_t next ();
 
-  // uniform distribution
+  // uniform distribution, 0 .. max (0, num - 1)
   uint32_t operator ()(uint32_t num)
   {
     return is_constant (num)
@@ -395,7 +433,7 @@
 
 typedef tausworthe_random_generator rand_gen;
 
-extern rand_gen rndm;
+extern rand_gen rndm, rmg_rndm;
 
 INTERFACE_CLASS (attachable)
 struct refcnt_base