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Hi, has any one had experience building a city block or scene and could tell me the best scale factor ? I just wanted to know if there are any problems, especially building something big like the Empire state building. I have experienced some strange clipping/viewport stuff which i managed to sort out somewhat. Are there any pointers you could give me ? Any don't do kind of things ?
Thanks

Hey!

One SI unit = 10cm so you can use this as a reference..
The camera clipping is found in the camera PPG under Primitive at the bottom...hope that helps ;)

cheers,
oli

Hi owei,
Yeah, I've been using 1 SI unit to 10cm. Is it not dangerous to make something really huge ? Any tips or should everything be ok ?
And thanks for the clipping info. I looked in to that some time ago. I suppose that made me a bit anxious. I guess you set in to the closest and furthest parameters for all round ease.

Well...I don´t know exactly, but it should work ;)

Fingers crossed .....here goes

'get parameters from scene' is quite good at guesstimating clipping planes. Once you've done that, you can tweak and see what happens in the viewport realtime. I need to change far/near mostly when doing depth-passes. SO they will vary per shot, depending on cam position/angle etc.

think an eazy to build relation to use, then you can adjust cliping planes, just dont go nuts,

For example you can render a 1 bil si units cube with no problems if you abjust the planes.
but most likely you will get some weird efects if you zoom on a vertex.. because the presision have been scaled too.
efects like jiter when you try to move camera etc.

So you have to balance micro and macro

Also you can always put your whole scene under a model and scale it down to your needs.

So the relations here are just theoritical.
I used many times 1si - 1m ,, on buildings with no problems.

really tiny stuff <.1 unit or really BIG scenes > 10.000's of units could have render errrors at some point, due to the floating point round offs.

For that matter, I never had any issues with big scenes. But when building the solar system, it might be more practical to set the SI unit a tad bigger ;-)

rob

Great feedback Folks. Makes me feel a lot more confident.













Keep Softimage alive

cheeseburger wrote:Hi, has any one had experience building a city block or scene and could tell me the best scale factor ?

We build cities, and the scale factor I use is 1 unit = 1 meter. Our biggest project is around 5 kilometers by 3 kilometers, and there are no problems even with small elements, such as 1 cm thick glass.

Using the "default" of 1 unit = 10 cm should also work fine for this kind of scale.

..well, of course you can use smaller scales, in that case, just take care of the specific render settings in some physical correct renders...some have parameters for the scene scale... don´t know about MR.. ;)