That was it Mike!  I had not declared them as local.  I didn't know that
directive existed.  Thanks for the help!

Arie

"Mike Williams" <mik### [at] nospamplease> wrote in message
news:B$i7SBABN9z7Ew+p### [at] econymdemoncouk...
> Wasn't it Arie L. Stavchansky who wrote:
> >I have the following:
> >
> >//macro to make a tube of rings of spheres
> >#macro sphereTube(height, tubeRadius, elements, bottomSurface,
topSurface,
> >place)
> >
> > #declare i = 10;
> > #declare shift = <0, 0, 0>;
> >
> > #while (i < height)
> >
> >  objectRing(
> >
> >   tubeRadius, //radius of ring
> >   elements, //number of objects in ring
> >   bottomSurface, //start texture of object
> >   topSurface, //end texture of object
> >   place + shift //place away from origin
> >
> >  )
> >
> >  #declare shift = shift + <0, ballRadius(tubeRadius, elements)*2*i, 0>;
> >  #declare i = i+1;
> >
> > #end
> >
> >#end
> >
> >The problem is that the macro inside the loop (which functions properly)
is
> >not being called more than once.  In fact, even the message I am given
says
> >there are only a certain amount of frame level objects, as opposed to a
> >certain amount of frame level objects times the height (which is the loop
> >condition).
> >
> >If you replace the macro inside the loop with a simple prmitive, such as
a
> >sphere, then you will see the many spheres.  Why is the macro not being
> >called multiple times?
> >
> >Thanks for your help,
> >Arie
> >
> >
>
> Since it works with simple primitives, I'd guess that one of the macros
> you call "ballRadius" or "objectRing" is clobbering the value of your
> counter variable "i".
>
> The way to fix this is to change your #declares into #locals. This
> allows each macro to have its own copy of the variable which then won't
> interfere with similarly names variables in the calling macro or in the
> top level of the scene file.
>
> When you use "#declare i" you are changing the value of the global
> variable called "i". So, if objectRing() uses "i" as its counter, and
> counts up to "elements", when control returns out from objectRing() into
> sphereTube(), the value of "i" has been changed from 10 to elements. If
> elements+1 is greater than height, the while clause of sphereTube() is
> satisfied, and the macro terminates.
>
> If this is the case, then you're lucky that height is less than
> elements+1, otherwise it could easily have gone into an infinite loop.
>
> --
> Mike Williams
> Gentleman of Leisure

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