View Full Version : New LW skeleton problem

07 July 2003, 10:18 PM
After exporting and characterizing, everything looks fine and works so far. However, when I choose "Control Rig Input" as my input type and then activate, the knees of my character go backwards, like a chicken, and they should be human knees.
The rotations of the bones are Zero when I import (except for the Hips bone). The model is facing Positive Z. All in all, everything looks to be perfect, except for the backwards knees when I activate the Control Rig.

If I change the input type, the knees snap back to their original position.

Any thoughts, any one run into this problem?

Edit: Also, I can't select any meshes in the view port (double clicking an object doesn't select it), but I can select from the Navigator. Any ideas on this one?

07 July 2003, 11:00 PM
I solved my second problem of not being able to double select the mesh in the view port. Instead of letting the exporter freeze my objects, I froze them first, then exported. Works now.

07 July 2003, 03:03 AM
Nevermind, I got it.

Apparently, even though my character is facing positive Z in Lightwave and all of the bone are positive Z, once loaded into Motion Builder the character would face Negative Z causing a bunch of things to go backwards.

So I turned my character to the Negative Z in Layout, and imported him to MB, everything is going as it should, the character is facing +Z. Weird.

solar power
07 July 2003, 02:39 PM
Its been stated before in other threads:

Since LW's and MB's Z-axes are reversed, either make sure your character is:

1)facing Z- in Lightwave, or
2)facing Z+ in Lightwave, and then your rotate the "Reference" null in MB so that he's facing Z- (Motionbuilder's Z+) before you characterize.


I think if you do your freeze during the export out of Layout it freezes at a the meshes 'Display Subpatch Level' setting in propreties.

I've been having a problem freezing meshes with wieghtmaps already applied:

If I freeze a model at a higher subdivision than 1, the wieghts don't get added to the additional vertices (in Modeler or in Layout in the fxb export process), of course, giving me an unusable model.

It seems that the fxb plugin will freeze your model at export from LW Layout using the 'Display Subpatch Level' setting in the meshes properties. But still doesn't re-apply the wieght maps to the newly created vertices if the setting is higher than 1. Going back and re-applying wieghts after a freeze is a real pain.



Good Luck.

07 July 2003, 03:45 PM
Yeah, I searched all the LW/MB threads for some info in the Z-axis problem, but found nothing (obviously I missed it). I know now.

Well, it turns out my selecting problem has less to do with the mesh, and more to do with my lack of knowledge of MB. When in "X-ray Mode" in MB, one cannot select objects, only the skeleton or effectors. As soon as I switched to "Models Only" view or "Normal" I could select the geometry.

Solar Power,
Currently, I have my character in MB with the mess frozen by the exporter at a display subpatch level of 2. All works fine for me in MB. The weighting has not suffered. Though I haven't brought it back to Layout. Does your problem occur when exporting only or importing?

07 July 2003, 01:45 AM
If I freeze a model at a higher subdivision than 1, the wieghts don't get added to the additional vertices (in Modeler or in Layout in the fxb export process), of course, giving me an unusable model.


Hello, I would suggest saving a copy of your model from LW with the subpatches frozen, use this model in your LW scene that you will generate the original .fbx from, then after merging with your final animation from MB back into LW, simply do a replace on the frozen object with your subpatch original. That's my workflow.

I believe that you have more control by freezing from LW than by letting MB do it for you. Plus, you can adjust any weight map errors in your frozen object before shipping into MB.

I hope this helps,

Jim Arthurs

solar power
07 July 2003, 06:20 PM
Hmm. Seems I've done something funky when making my wieght maps. Every time I try a freeze (even in Modeler) I end up with big spaces between maps that should be overlaping.

Do you all use Vertex paint when making weights, or use a lower falloff percentage?

I usually just select points then apply a new wieght map.

But, many have said they dont encounter this 'new vertices have no wieghts' problem.

Anyway. "Knowing is half the battle" :)

07 July 2003, 03:19 PM

I generally select a group of points and make a weight map. If I want to feather intensity I just use the expand and contract display tools to isolate points and I work with values such as 25%, 50%, 75%, 100% and not much else. Easier to then make overlapping maps with the reverse %'s. Generally I don't use Vertex Paint because I haven't taken the time to learn it, though I'm sure it offers advantages.

One thing to look out for is areas where you have set your weight values at 0% vrs points where the weights are completely cleared. These are not identical conditions and will freeze with different results.

I'd suggest trying some simple tests with the above info and I bet you'll get a good combination going...

I hope this helps,

Jim Arthurs

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