Hi Kevin, thanks for reporting this FBX issue!

> However if the normals face inwards and you import into
> max, once you flip all the polygon faces (in max) the crazy
> patterns start again on each polygon.

From your description, it certainly sounds like a bug in Max's flipping function.

Can you do a test where you create a mesh directly in Max, export it to FBX, then re-import and try flipping it? If that runs into the same problem then that would verify it.

Unfortunately it is not too unusual for polygon modeling programs to actually have bugs in their flip functions when they have kind of tried to "bolt on" vertex normal support when it was not initially supported. They sometimes forget to flip the vertex normal data at the same time as the polygon orientation flip.


> As far as I know there is no way of knowing which way a surface faces in MoI.

No, not currently but I do want to add this though.

- Michael

Thanks Michael

I created a cylinder in max and flipped all the normals. Exported it to FBX. Then created a new file and reimported it. Once I tried to flip the normals on all the faces the right way the crazy pattern showed again. So yep looks like a bug in max or the FBX plugin.

It seems to be fixable by converting from editable poly to mesh and back to editable poly.

I'll have to keep working with obj (quads and tris) in the meantime as there seems to be less problems with this format.

Hi Kevin, yeah repeating the problem with objects generated only in Max confirms that it is a bug in there somewhere. My guess would be the flip function is probably not flipping the vertex normals like it should.

One thing that you might check is to make sure you have the newest version of the Max FBX plug-in, which I think is 2009.3 - you can download it from here:
http://usa.autodesk.com/adsk/servlet/index?siteID=123112&id=10775855

That could possibly help if you are currently running an older version.

- Michael

Thanks for that Michael.

I had the .1 version of the plugin which I downloaded only a few months ago when testing FBX for you. The .3 version of the plugin just fixed all the problems I previously described in this thread so I can start using FBX again !

Hi Kevin, that's great news!

I think that the Max OBJ importer does not bring in the vertex normals - getting in vertex normals really tends to help for getting clean shading.

So now with FBX working properly that should hopefully bring across the best transfer with all the shading information intact.

- Michael

Yep, thanks for the help with this. It also makes for a very clean mesh when using the ngon option for export to FBX so I am very happy it all works well now.

The part that is kind of frustrating is that actually the same data is being written by MoI to either OBJ or FBX, I mean it is all the same points, polygons, normals, etc...

They just seem to never get around to updating their OBJ importer to the same level as the FBX importer. If it was set up better, they should use all the same internal functions for processing n-gons and normals between either format instead of it being completely separate code and having one working better than the other.

But oh well, at least there is now a method that works!

- Michael