SOLVED: Issue with foot bone orientation--EPIC leg / EPIC foot component

[Chris_Bullock]

Hi all,
Been lurking for a while, and first of all wanted to say thanks to everyone contributing to mGear. It’s nice as an indie developer to have something like this already built, but also have access to the source to modify to our needs as well. And as a former Softimage user, it’s nice to still see a community of people who miss/loved it, and want to bring things backwards into Maya as well I’m looking forward to helping out where I can as well.

Now, to my current issue: I can’t seem to get my foot bone/joint to orient properly. As you can see in this image, the x-axis is pointing upwards, when I’d prefer that it be pointing forward (similar orientation to the toe joint).

Some notes to help with troubleshooting:

I’m attempting to work with an X-forward, Z-up space (in my experience, x-forward is pretty common in games pipelines, since it’s consistent, no matter what the Y and Z axes are doing, and in working with UE, it seems to want X-forward, Z-up, anyway).

As noted in the title, I’m using the EPIC Leg and EPIC Foot components. (mGear 3.7.8)

The only Joint Orientation options I have set on either component is a -90 on the X on the Leg component. In resetting this back to 0.0, it doesn’t affect the foot joint in any unexpected way, and does not get me what I want.

In case it matters, I am using some custom naming. Here are my settings:

Any help/suggestions people can offer would be greatly appreciated. Thanks!

-Chris B.

[Chris_Bullock]

I just checked against the MetaHuman rig template, and it too seems to be having this issue. This issue affects the twist joints on the lower leg, and they end up flipping quite a bit.

[Miquel]

Hello @Chris_Bullock
is that what you need?

or for the leg component

[Chris_Bullock]

Hi @Miquel, thanks for replying. I actually already have that set on the leg for the twist joints on the leg. In testing, it seems the Joint Orientation Offset only affects the toe joint(s) on the foot component. The foot joint is picking up a different orientation from both the leg twist and and the toe joint.

I was able to “fix” it by editing the component itself (well, duplicating the component, and then editing it). I believe I fixed it when fixing the twist ref, since that was not working correctly (also exists on the mGear MetaHuman rig). It’s now working such that the foot joint orientation matches the twist joints, with the x-axis pointing “down”. This is a fair compromise for me for now. I might look into making my duplicated component have the foot joint oriented more in line with the FK control, but I think I can adjust that myself.

So, I guess ‘my’ issue is solved, but the EPIC_Leg_01 component still has the twist issue on the lower leg.

Thanks!

[Miquel]

Hello @Chris_Bullock

@Chris_Bullock

So, I guess ‘my’ issue is solved, but the EPIC_Leg_01 component still has the twist issue on the lower leg.

I am still not understanding completely your “issue”. Can you illustrate it with more images or a sample scene with the joints orientation that you are looking for?

[Chris_Bullock]

Sorry, I just double-checked the Metahuman rig, and it looks like it’s working fine in there. My mistake. Maybe it has something to do with trying to use the epic leg and epic foot components in an x-forward, z-up pipeline? It seems like it’s looking for it to be in a negative-y-forward, z-up pipeline. I think I saw a similar issue with the epic spine component, too. I’d have to dig deeper into it. In any case, I think we can mark this as ‘solved’ for now–chalk it up to me using the component in a way it wasn’t meant to be used.

[Chris_Bullock]

Here’s the solution I came up with for my ‘custom’ component based off the EPIC_leg_01 component:

It might be a little hacky, a more elegant solution would be to define what the rig ‘forward’ axis is, similar to using the up_axis attribute, but obviously, that requires a lot more plumbing.

[Miquel]

@Chris_Bullock thanks for all the info. I will change the title to solved

[Andy]

@Chris_Bullock

a more elegant solution would be to define what the rig ‘forward’ axis is

Sorry if this has been addressed somewhere else but I’m curious about this idea. I also work in a Z-up, X-forward pipeline and notice a lot of the components act strange in this orientation. I usually have to build everything -Y-forward and then rotate everything to X-forward after-the-fact.

It would be great to be able to define the orientation in the root guide component options instead of having to copy/edit the python modules or do custom steps after the rig build.

Is there any chance this is on the roadmap or is it totally out of the question?