--- /dev/null
+
+You can say "set isosamples 30,40" now to get different isosampling
+rates for the first and second dummy variables (x,u resp. y,v). This
+will affect surface-plots in hidden3d- and nohidden3d-mode. It gets
+rid of the necessity of having to change samples in hidden3d-mode when
+you actually want to change the isosamples for the first dummy
+variable. For people that are lazy and for compatibility you can also
+type "set isosamples 30". This will set the value to 30 in both
+directions. For completeness I did the same with "samples". Thus you
+can say "set samples 50,100" to get different sampling rates for each
+dummy variable. This only affects surface-plots in nohidden3d-mode.
+Again, you still can say "set samples 50". This will set both sampling
+rates to 50. For 2d-plots the first value of samples is used.
+
+Summary:
+
+Suppose isosamples is set to 4,5 in hidden3d-mode. The grid evaluated
+for hidden3d-plots will look like this (* denotes points that get
+evaluated):
+
+ |------ isosamples #1 -----|
+
+ - *--------*--------*--------*
+ | | | | |
+ | | | |
+ i | | | |
+ s *--------*--------*--------*
+ o | | | |
+ s | | | |
+ a | | | |
+ m *--------*--------*--------*
+ p | | | |
+ . | | | |
+ | | | |
+ # *--------*--------*--------*
+ 2 | | | |
+ | | | |
+ | | | | |
+ - *--------*--------*--------*
+
+Suppose isosamples is set to 4,5 and samples to 10, 9 in
+nohidden3d-mode. The grid evaluated for hidden3d-plots will look like
+this:
+
+ |------ isosamples #1 -----|
+
+ - *--*--*--*--*--*--*--*--*--* -
+ | | | | | |
+ * * * * |
+ i | | | |
+ s *--*--*--*--*--*--*--*--*--* s
+ o | | | | a
+ s * * * * m
+ a | | | | p
+ m *--*--*--*--*--*--*--*--*--* l
+ p | | | | e
+ . * * * * s
+ | | | |
+ # *--*--*--*--*--*--*--*--*--* #
+ 2 | | | | 2
+ * * * *
+ | | | | | |
+ - *--*--*--*--*--*--*--*--*--* -
+
+ |------- samples #1 -------|
+
+
+BTW: The examples above also show how the bottom grids will look like
+both in noparametric- and in parametric-mode. Thus you can get a rough
+idea of how the mapping from (u,v)-space to (x,y,z)-space works by
+drawing a bottom grid in parametric-mode.
+
+Best regards,
+
+Carsten