How to fix Collada produced by FBX

Other Standards COLLADA
1

Hi,

I tried to use the latest FBX SDK (2011.3.1) to load FBX files and save them as Collada files in order to be able to import FBX files in Panda3D.
Unfortunately the resulting Collada files are not usable for several reasons, among them:

  • There’s a Maya specific extra technique

<diffuse>
    <texture texture="Map__2-image" texcoord="CHANNEL0">
        <extra>
            <technique profile="MAYA">
                <wrapU sid="wrapU0">TRUE</wrapU>
                <wrapV sid="wrapV0">TRUE</wrapV>
                <blend_mode>ADD</blend_mode>
            </technique>
        </extra>
    </texture>
</diffuse>

  • It assigns a texcoord channel name that isn’t referenced anywhere else in the file (in the previous code sample, no geometry uses “CHANNEL0”…)

  • Every polygon is exported twice, a first time with a basic material (only diffuse color, specular color, etc.) and a second time with a textured material --> this doubles the number of polygons of each model without any valuable reason

Anyway, the resulting Collada file cannot be opened correctly either with OpenCOLLADA or Panda3D’s “dae2egg”.

Anyone has any experience on how to “fix” it and make it understandable by common and well-reputed Collada importers such as OpenCOLLADA?

Thanks

2

There needs to be a <bind_material> for the texcoord to resolve explicitly. It’s possible that FBX is doing something implicitly to resolve the symbol in the case where it is unambiguous.

Regardless, these are FBX bugs that you should report to Autodesk.

You might try updating to FBX 2012 as I hear it is much improved.