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View Full Version : Collada export wonkiness?



bluesmike
06-11-2010, 05:29 AM
This may be a well known issue, but for me it's something new, as I've never needed to work with collada files before. Now I have a client who wants models in collada format -- most of these models have UV mapped textures-images. I've been trying everything to get a usable export, but either one or more of the UVs are screwed up, or some polys are strangely missing. Any idea how you get good collada exports from LW 9.6? Is it even possible? These are simple models I'm making in LW 9.6 and need to be exported as Collada files for use by my client.

Thanks.

Mike

borkus
06-11-2010, 08:50 AM
I haven't had to use that format yet, but will be soon and the research I've done so far is to use Blender as the exporter. Some have said that they have had no issues while others said it's not working correctly. But, it's a simple workaround and doesn't seem to be much of a hassle.

lasco
07-13-2010, 08:18 AM
Collada exporter doesn't work correctly for some reasons Newtek could easily correct. (will soon post more about it).
Blender seems to work a little better for the moment, at least for geometry.

walfridson
07-13-2010, 09:35 AM
Which programs are you viewing the exported result in?

lasco
07-13-2010, 11:24 AM
Sketchup, personnaly.

Actually LW Collada exporter does not always write the EXACT point coordinates.
Depend on if the polygones are near from the absolute center.
If not, a given point will be written in the .dae with for example an Y value at :
230,458 m

instead of :
230,4577 m

This rounding causes that your perfectly flat polygones are very littely deformed and not recognized as flat faces by the soft that imports the files.

I made the test with a single polygon that Sketchup could'nt load and after having typed the exact values in the .dae file it worked a charm.
To solve it on a whole model the workaround I found is to open the exported .dae file and replace
<unit meter="1"></unit>

by

<unit meter="0.01" name="centimeter"/>
which is the setting of .dae files exported by Blender.
Of course this suppose to rescale the model imported in Sketchup.

And unfortunately it does not solves evrything yet because there are stille polygons that are "REALLY" non-flat (non recognized) for this app, while you usually set a 0,5% tolerance in LW.

So the definitive way to solve seems to be :- set the flatness tolerance at an even lower lever (0,2 or 0,3%)
- then triple or subdivide all "non-planar" polys
- then export .dae
- then change the unit setting in a text app
- then import it in the 3D app and if necessary scale it.