ArchiCAD to 3DS Scale Issues

[kaylmyers]

So in theory, Archicad draws everyhting in scale. Which is cool, but when I export to 3ds, it keps the "scaled down" scale. Then, I'll uniform scale the object by the scale factor for whatever scale it was set up. This gives me the correct size. HOWEVER In the modifier stack, it retains the number of the old scale. So if I export a 48' object at 1/4" scale in archicad, it will import to 3ds at 1'. so i scale it up 4800% to give me a 48' object, which it does. When I check the dimensions on the object itself (or add parametric modifiers or anything else), it still says 1'. Has anyone else had this problem? Is there a way to fix this?

[bricklyne]

I think the problem you might be having might be originating from the ArchiCAD end of things. If you don`t specify what unit you`re exporting it to in the 3ds export dialog window, it will either use the ArchiCAD working dimension unit, or assume a unitless model and let the importing program ( in your case, I would assume MAX), do the unit conversion and model scaling. Which is all fine, if you have the units in both programs set up to work well with each other (i.e the same). However, I have found that the best way of ensuring that everything is in order is to set it up straight from ArchiCAD while exporting and then uncheck the Cconvert units to system scale' option in the MAX when importing. Of course all this presumes that the working units in both ArchiCAD and MAX are both synchronized ( i.e . 1 unit = 1 inch in both programs or 1 unit = 1 meter in both, etc. ), otherwise it will screw it up again.

By the way with the above method I rarely have to rescale the model as everything fits to perfect scale and you can always check this in MAX using the 'measure distance' tool from the Tool menu, to measure the length of something you know for certain, like a door or a window.

 

I have to point out ( and forgive me if you`re already aware of this, but it is easy to overlook), that in both programs, working units are not necesarily the same as dimensionin units and as such one can go under the assumption that everything is fine in imperial system when the program is actually calculating everything in Metric units (= beacoup errors in import-export situations, and further on in rendering calculations). So you might also want to check that, in both cases, and more so in MAX under the "Customize" menu under units. For some strange reason, Max is set up to assume that one can work under a unitless environment, which makes absolutely no sense to me, but which apparently quite often seems to be the default unless you set it otherwise.

So, at the end of the day, once you have everything working under the same units you abosultely have to uncheck the convert units option during import or MAX will convert the units wrong and re-scale your model to the wrong size.

 

I hope this helps, and sorry for the long reply.

[kaylmyers]

Thx for the reply. That should help. When importing / exporting i've always left all the settings default. So I'll look more into that next time.

 

As far as the units thing goes, the first thing I always do (autocad training) is set my units. So in know they're both set to imperial.

 

Thx again.

 

-Kayl