Author Topic: Is there any benefit in moving from mm to cm for archiviz?  (Read 1570 times)

2021-06-29, 06:12:01

Luke

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Just wondering if there is any derived benefit of changing my workflow in max from mm to cm?
I've worked in archiviz for 13 years and just always used mm, but after reading around I've noticed that a lot of ppl are using cm...?

2021-06-29, 07:18:09
Reply #1

aaouviz

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I use mm too. From some light research I don't think I've ever read anything that says one is preferred over the other.

I think it's simply a matter of choosing something and sticking with it; being consistent.

I'd love to hear others opinion on the topic though. I often think we need some sort of 'formats and conventions' specified for our industry. This is something we're lacking.

2021-06-29, 10:51:19
Reply #2

dj_buckley

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CM is a happy medium for the range of scene scales you come across in Arch Viz.  From smaller interiors to larger exteriors.  There were some issues with zooming (not sure if they still exist), for example if set to M you couldn't zoom into an object close enough to get smaller details.

I'm using CM, these days and haven't had any viewport issues for a while.

2021-06-29, 11:15:29
Reply #3

PROH

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Hi. It's all about scene scale. Max is a single-precision program (like most DCC's) and therefore can't calculate very large numbers precise. That means, that the further away from drawing origin (0,0,0) the less precision.

That's the reason Max warns you if the scene is to far away from drawing origin, and that's why it's impossible to draw a straight line far away from 0,0,0.

So use the system unit that fits your need:
City scale - meters
Interior scale - cm
Product scale - mm

Also remember that Max has two unit settings: 1) System Units, and 2) Display Units. All behind the scene calculations are done in System Units, and most UI measures are following the display Units.

NB - When using meter as System Units you should set decimals to 4 to keep precision down to millimeters.

Hope it helps

2021-06-29, 11:19:36
Reply #4

NicolasC

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Great summary, PROH :)
« Last Edit: 2021-07-05, 10:22:37 by NicolasC »
Nicolas Caplat
CG supervisor / teacher / artist

2021-07-03, 20:50:11
Reply #5

zaar

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I fully agree with PROH, and I think that way of working is pretty much standard. But I never thought of changing the decimals for meters. Great tip!

Presumably all the US artists work in feet? I’ve never tried it in production, but since Revit and many Autodesk products seem to use that internally with problematic conversions to metric in Max, I’ve thought of using it as system units, but setting display units to MM. Just the thought of it feels a bit dirty ;) but I think that would give the least amount of problems taking things from Revit to Max. And the UVWs that never seem to get their scale converted properly works too from my tests.
Anyone tried this?

2021-07-05, 16:40:53
Reply #6

Philip kelly

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Just thought I would ask, why the bring it back to 0,0,0 is still an issue with Max, every drawing now has to have been set up to it's correct coordinates, for the past 10 years.
Why haven't Autodesk fixed the issue of this in max?
Dell Precision T7910

2021-07-05, 18:02:47
Reply #7

pokoy

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I fully agree with PROH, and I think that way of working is pretty much standard. But I never thought of changing the decimals for meters. Great tip!

Presumably all the US artists work in feet? I’ve never tried it in production, but since Revit and many Autodesk products seem to use that internally with problematic conversions to metric in Max, I’ve thought of using it as system units, but setting display units to MM. Just the thought of it feels a bit dirty ;) but I think that would give the least amount of problems taking things from Revit to Max. And the UVWs that never seem to get their scale converted properly works too from my tests.
Anyone tried this?

Not a good idea - if all the content you work with and exchange with others is in metric, do not infuse any imperial system in there. Even though in max all units will be *displayed* as metric, whenever you export it'll have a different scaling. Same with importing stuff - if it comes in metric units, you'll have to rescale stuff.

I often have to deal with data from the US and it means a lot of work to rescale properly. But if I just chose to set display units to metric and not actually rescale it would mean that when I mix US assets with metric stuff they would not have the same scaling. So basically you'd just postpone the problem.

There are all sorts of problems with rescaling in Max, that's why it's best to choose the right units in the beginning.

2021-07-05, 18:09:10
Reply #8

etbali

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