--- a/src/zoom.hpp	Fri Jun 08 18:23:26 2007 +0000
+++ b/src/zoom.hpp	Fri Jun 08 18:45:14 2007 +0000
@@ -37,14 +37,14 @@
 {
 	if (zoom == ZOOM_LVL_NORMAL) return value;
 	int izoom = (int)zoom - (int)ZOOM_LVL_NORMAL;
-	return (zoom > ZOOM_LVL_NORMAL) ? value << izoom : value >> -izoom;
+	return (zoom > ZOOM_LVL_NORMAL) ? value << izoom : (value + (1 << -izoom)) >> -izoom;
 }
 
 static inline int UnScaleByZoom(int value, ZoomLevel zoom)
 {
 	if (zoom == ZOOM_LVL_NORMAL) return value;
 	int izoom = (int)zoom - (int)ZOOM_LVL_NORMAL;
-	return (zoom > ZOOM_LVL_NORMAL) ? value >> izoom : value << -izoom;
+	return (zoom > ZOOM_LVL_NORMAL) ? (value + (1 << izoom) - 1) >> izoom : value << -izoom;
 }
 
 #endif /* ZOOM_HPP */