Index: math.h
===================================================================
--- math.h	(revision 756)
+++ math.h	(revision 757)
@@ -185,6 +185,9 @@
 This function will return ##0## if the point is behind the camera (and then,
 probably not interesting), and ##1## if the point is in the POV of the 
 camera ("in front of" is more exact).
+
+warning 1: the camera must be placed before calling this function.
+warning 2: this function will replace the camera by itself.
 **/
 
 #endif