fog question

[Keith W. <kw...@cs...>]

Is there any way to make fog on work as a function of X and Z, and not of
Y?  I am building an outdoor natural environment.  I would like to use a
"horizontal fog", one that only works as a function of X and Z.  This
would alleviate having to provide an infinitely distant visible horizon
and would add a nice ambience to the setting...as well as being
authentique to the kind of setting I am working on (rainforest).

However, I would like a clear blue sky to be visible overhead.  I don't
want the fog effect to drown out the sky dome object that will hang over
the entire environment even though that dome must be fairly far away in
order to surround the entire area of the environment.

The dome clearly has to have a radius as least as great as the radius of
the environment, so that it can span the environment without magically
cutting down through the ground.  But if I am forced to set the fog
distance that far, then the fog distance stretches across most of the
world and I lost the point of using fog in the first place, a means to
limit the range of visibility.

Any thoughts?  Thanks.

________________________________________________________________________
Keith Wiley                                kw...@cs...
http://www.unm.edu/~keithw                 http://www.mp3.com/KeithWiley

"Yet mark his perfect self-contentment, and hence learn his lesson,
that to be self-contented is to be vile and ignorant, and that to
aspire is better than to be blindly and impotently happy."
                                           --  Edwin A. Abbott, Flatland
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