3eda8ea4$1@news.povray.org...
> Those are interesting pics (and very neat, too).
Thanks!

> I'm curious as to what the memory usage
> is like on your computer when rendering
> these scenes, and how you would handle
> getting previews of such scenes
> (either stills or test animations)
> and how long they would take.

Meshes in POV-Ray have two major benefits:
1) they can be instanciated, i.e. the first copy of the mesh is the only one
that counts. The other copies can be rotated, translated, scaled etc. and
only add the price of the pointer (if I'm telling nonsense, people who
really know the code will correct me). A tree mesh of 100Mb (mesh2) can be
used once or 4000 times with a minimal difference in memory cost. I didn't
record the total RAM use for the but it was well below the 1Gb I have, and,
as I said, these scenes all use radiosity (and other things than meshes).
Without any additional elements, the 4000-tree scene will use the RAM of the
initial tree + 4000 pointers.

2) they render extremely fast

As this applies too to height-fields (static or generated on the fly), the
consequences in terms of landscape generation are huge. A single
height-field tiled properly and 5 different trees can generate an entire
forest, quickly, and within the memory cost of the initial elements (see the
page here for examples (with code) of on-the-fly large height-fields, tiled
or not. http://www.oyonale.com/ressources/english/sources13.htm).
Actually the main limitation of scenes with large meshes and height-fields
is not the render time but the parsing time, as a 100mb meshes need to be
read anyway. To speed up things during tests, I often use dummy props
(simple primitives or low-poly meshes) and low-res height-fields (which can
be done in the code if they're function-based).

The Forester page (http://www.dartnall.f9.co.uk/) has impressive animations
of big POV-Ray generated landscapes, btw. Perhaps he has more insight about
how he did those (render times, memory cost etc.).

This doesn't mean of course that an hybrid engine wouldn't be interesting...

>and also to shorten render times for scenes that
>don't need global illumination effects.
Do such scenes really exist ;-)

Gilles

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