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View Full Version : Precision limits?

jeric_synergy
05-05-2011, 01:07 PM
I know that LW can only be used to model things SO big or SO small, but I disremember: is it the absolute size, or the RANGE of size?

For instance: I'm contemplating modeling a space habitat, and it could be up to 10 kilometers long. If it were that size, is it possible to model, say, a bolt on the airlock while keeping the entire model?

(Although, obviously, it would make more sense to break it up into sections for the sake of competent RAM usage.)

lertola2
05-05-2011, 02:40 PM
A little testing in modeler shows that an object can be any size from smaller than 0.1 um to larger than 1 billion meters as long as it is centered on the origin. But modeler will not display the objects properly at either extreme of size. However the further the object is from the origin the less precise its shape can be. The attached image shows a 1 inch wide bolt on the left. On the right the same bolt was moved to 100 km on the x, y and z axises and back. Obviously it is distorted but it would still look like a bolt from a reasonable distance. So I do think that you could have bolts of this size on a 10 km object although you will not be able to position them as precisely as if they were near the origin.

-Joe

jeric_synergy
05-05-2011, 04:20 PM
Lertola, thanks for your research.

Now the question is (which I will look into myself) is: while the distortion in Modeler is about distance from the origin, what happens in Layout when two small, detailed objects are 100km apart?

(As a practical matter, one could always edit, so it's actually more of an academic question.)

BTW, that's a 'nut', not a bolt. And your avatar always makes me smile.

lertola2
05-05-2011, 04:59 PM
And your avatar always makes me smile.

Thanks. The image was a failed attempt to make an icon for my defunct mapping software. It was to creepy for my website though.

-Joe

archijam
05-05-2011, 05:00 PM
Layout deals with the geometry fine AFAIK, as it is translating it, not constructing it at that distance ..

But as lertola mentioned, the exact positioning (translation+rotation) will be affected at some distance, as you are losing decimal accuracy in the end ...

jeric_synergy
05-05-2011, 06:02 PM
Thanks. The image was a failed attempt to make an icon for my defunct mapping software. It was to[o] creepy for my website though.

-Joe
At least you found a use for that volumetric preset.