Anyone know how to make heightfields using the data_2d functions of MegaPov?
Here is a cut from one of David Sharps posts to another confused person:

(how data is written to file)
<<<<<<<<<<<<<<<<<<<<<<<<<<
for x=1 to L0
    for y=1 to L1
        for z=1 to L2
              print_to_file( function(x,y,z))
      next z
    next y
next x

Here,  function(x,y,z) is supposed to represent the
value of the function at the point x,y,z
>>>>>>>>>>>>>>>>>>>>>>>>>

Now, this is a 3d 'example', but I take this to mean the data maps an
isosurface where all the data points lie in the range <1,1,1> to <L0,L1,L2>.
This just doesn't seem to be the case in practice (not to me, anyway :).
This also seems to be the opposite of what's stated in the megapov help file
(I mean the x,y,z ordering of the data).

All I want to do is make 'heightfields' using the 2d equiv. functions. I
realise I could convert my data to a tga and make a normal heightfield. My
reasons for not doing this are for a program I want to write. For the 2d
case, your manual section in the MegaPov html help says the y-sample
parameter is ignored. OK, does this mean that:
<3,1,3,0> will give the same results as <3,2,3,0> or <3,10e34,3,0> or
whatever L1 is set to?

Do all these example param. vectors mean the data_2d functions expect 3*3=9
values?

Where in 3d space are these 9 values mapped?

I thought the values were supposed to stand for values as would be obtained
by an equivalent iso-function. Does this mean that if my isosurface was
computed with a threshold of 2, any data-values equal to 2 would lie on the
isosurface?

I would appreciate any help, guidance, tutorials, links, criticism; anything
that will show me how to do this, or why I should give up on the idea :)

Thanx,
Dave

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