add random numbers generator

essai.pov

@@ -10,6 +10,9 @@ global_settings	{
 	max_trace_level 10
 	}
 
+#declare R2 = seed(clock);
+#declare foo = rand(R2);
+
 #include  "colors.inc"
 #include  "metals.inc"
 #include  "textures.inc"