--- deliantra/server/include/util.h	2009/01/12 03:40:21	1.87
+++ deliantra/server/include/util.h	2009/05/05 04:51:56	1.88
@@ -120,13 +120,25 @@
 template<typename T>
 static inline T sign0 (T v) { return v ? sign (v) : 0; }
 
+// div* only work correctly for div > 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; }
+template<typename T> static inline T div    (T val, T div)
+{
+  return expect_false (val < 0) ? - ((-val + (div - 1) / 2) / div) : (val + div / 2) / div;
+}
 // div, round-up
-template<typename T> static inline T div_ru (T val, T div) { return (val + div - 1) / div; }
+template<typename T> static inline T div_ru (T val, T div)
+{
+  return expect_false (val < 0) ? - ((-val                ) / div) : (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 div_rd (T val, T div)
+{
+  return expect_false (val < 0) ? - ((-val + (div - 1)    ) / div) : (val          ) / div;
+}
 
+// lerp* only work correctly for min_in < max_in
+// Linear intERPolate, scales val from min_in..max_in to min_out..max_out
 template<typename T>
 static inline T
 lerp (T val, T min_in, T max_in, T min_out, T max_out)