I am creating my models using 3ds Max, exporting them as FBX models, and I seem to be having 2 issues.

1. Since 3dsMax uses right-handed coordinate system with the Z-axis up, and XNA uses right-handed coordinate system with the Y-axis up, I exported the model, setting the Up Axis (in the export window) to Y-up. This does not make a difference when displaying the model in my game, and it seems to keep the Z-axis as up. I can think of a quick fix to just rotate all the objects that I export 90 degrees (into the correct position), but I don't think it seems more like a hack than a solution.

2. In addition to the problem above where my model is rotated incorrectly, the normals seem to be facing in the wrong direction. When I apply the modifier Normal to the model (inside of 3ds Max), and I flip the normals, the object draws properly in the game. Once again, this seems more like a hack.

Is it possible that the export changes coordinate system from right-handed to left-handed, causing issue #2 to occur?

Any help is appreciated. Also, if this post is not in the correct place, please let me know and I'll move it to the proper forum.

First, make sure you're using the latest FBX plug-ins from the Autodesk download site.

Second, In the Model Processor options, you can set up rotation for the model, and you can also choose to flip winding of your triangles, which will fix the "inside out" look.

Or you can try the kW X-port exporter, which may actually work better ;)

jwatte:

First, make sure you're using the latest FBX plug-ins from the Autodesk download site.

I'll second this. I've been using 3DS for all the models in my most recent game, exporting to FBX, and have had no issues (well, except when I try to get fancy with materials, but that's an entirely different problem). My normals are pointing in the correct direction (even when I flip them intentionally), and the model is correctly oriented in my game.

I am also experiencing this issue.

3ds Max 2010 32-bit
XNA 3.1
Latest Autodesk FBX exporter (Downloaded and installed this week)

FIX: As Jwatte suggested, set the "Swap Winding Order" check-box to TRUE. ( Visual C# -> Solution Explorer -> [select your FBX file] -> Properties dialog -> Content Processor/Swap Winding Order)

This might help. 

If you're using the BasicEffect to draw your model, don't forget to multiply the world matrix by the mesh's ParentBone.Transform, e.g.,

foreach (ModelMesh mm in mdl.Meshes)
{
    foreach (BasicEffect be in mm.Effects)
    {
        be.World = mm.ParentBone.Transform * mwrld;
        be.View = mview;
        be.Projection = mproj;
    }
    mm.Draw();
}

Good luck.

The FBX exporter in 3dsmax should have a drop-down called "World Coordinate System Up Axis".  Flipping this between Y and Z will solve the problem.

Mithra:

The FBX exporter in 3dsmax should have a drop-down called "World Coordinate System Up Axis".  Flipping this between Y and Z will solve the problem.

This has no effect at all when I export and I have the most recent FBX exporter for Max9. Any other ideas? I'll check again though.

Hey,

Did you ever find a fix for this, as I have not had this problem before but it is occuring now. The y / z axis does not make a difference to the import when I change it in the exporter. I did notice that in my model creation (3DS Max), all the axis are correct except for the left hand viewport which says the Z axis should be pointing up, but the Y axis is instead. Is there anyway to realign this, because the standard hierarchy/affect pivot only/re-align to world does not seem to be doing this, neither does the affect pivot only/reset pivot button.

Thanks

I re-installed the most recent plugin and it has worked ever since.