Christoph Hormann wrote:

> Stefan Viljoen
>> 
>> object
>> {
>>         Ground
>>         rotate <90,0,45>
>>         translate <50,-20,0>
>> }
>> 
>> #declare loc = trace(Ground,<0,0,5>,-z);
>> 
>> sphere
>> {
>>         <0,0,0>,0.25
>>         translate loc
>> }
> 
> What did you expect this to result in?  If you think the sphere will be
> placed on the surface of the object you obviously have misunderstood
> something about how transforms work.  You will either have to remove the
> "rotate <90,0,45> translate <50,-20,0>" from the object or add it to the
> sphere as well.

Hi Christoph!

I expected it to result in the sphere placed correctly on the surface.
Obivously I made a mistake. I guess I misunderstood the docs... from
reading them it said that the trace() macro will return the place where a
the ray, shot from the coordinate given, intersects the given object's
surface - I thought of this in terms of a "viewing ray" (?) i. e. that will
return a surface it intersects, no matter how far away or in what
orientation that surface is.

Obviously I was wrong. Thanks for the correction!
 
Regards,
-- 
Stefan Viljoen
Software Support Technician
Polar Design Solutions

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