--- deliantra/server/include/util.h	2007/04/21 22:57:16	1.41
+++ deliantra/server/include/util.h	2007/05/26 15:44:05	1.45
@@ -4,11 +4,21 @@
 //#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
 
+// 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>
@@ -47,6 +57,13 @@
 
 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 +281,18 @@
   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);
   }
 
@@ -436,5 +453,8 @@
 
 int similar_direction (int a, int b);
 
+// like printf, but returns a std::string
+const std::string format (const char *format, ...);
+
 #endif