In article <3CA39043.4D0DF734@gmx.de>, Tim Nikias <tim### [at] gmxde> 
wrote:

> So, when using meshes in unions, how efficiently are they saved?

A copy of a union containing a mesh will get a copy of the mesh, but 
that mesh copy will only contain a reference to the original data, just 
like ordinary mesh copies. (I'm making an assumption here, I haven't 
tested this...but if it does something different it is probably a bug)


> How do unions save anyway?

They generally don't. They are intended to make manipulating shapes more 
convenient. They are also useful because they can help you set up a 
bounding tree to speed tracing, but they don't help memory use at all.


> How are scaled instances of meshes handled?

The transformations are stored separately from the mesh data. Scaling a 
mesh doesn't affect the data.


> When putting a union around 2000 spheres and cylinders,
> does it make a difference when using instances of that
> union-object, or when rather placing several of those
> 2000 spheres and cylinders directly?

No substantial difference. If you make a union, POV obviously has to 
store the union itself, but that doesn't take much space. If you are 
asking if unions also use the shared data method meshes use, the answer 
is no.

-- 
Christopher James Huff <chr### [at] maccom>
POV-Ray TAG e-mail: chr### [at] tagpovrayorg
TAG web site: http://tag.povray.org/

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