Unable to use fk toe control after reverseFoot

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Hello,
I think reverseFoot component may not work well with fkikBlend.
For example,use electra rig in content library.(https://www.sidefx.com/contentlibrary/electra-rig/)
Reset all in sceneAnimate,switch to fk with "L_Limb_abst".
Rotate "calf_l_fk" and the leg moves,but the toe still pointing towards front,and it's not rotating with "ball_l_fk" contorl.

Back to ik,everything works.

I checked rig logic,it seems toe joint is drivn by some "lookat constraint stuff".
That seems to work in ik with reverseFoot,not with fk.


Btw,I do tried to change orders of autorig like:multiik---reversefoot---fkikblend,and the result is good fk and bad ik.(unable to use ik toe/ball control)

So it's a little bug or some wrong setup maybe?

Attachments:
toe_not_following_foot.png (1.9 MB)
lookat?.png (58.8 KB)

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I'm not sure whether this is a bug or perhaps more of a rig limitation. If you want, please submit a bug.
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edward
I'm not sure whether this is a bug or perhaps more of a rig limitation. If you want, please submit a bug.
Hi,Edward.
I think it's not bug, just the reversefoot component script in autorig is not fully tested with fkikblend.
The "t/r/s" input port of TransformObject is overriding "local" input port.
If you check the image above about rig logic,"lookat" subnet from reversefoot is overriding "fkikblend" subnet,so fk toe contorl is disabled.

I can use my own component script to create reversefoot,it's not hard to fix.I just think it might be better if beginners tring to create rigs only with autorig component would get a nice fkik setup.
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yxnh
edward
I'm not sure whether this is a bug or perhaps more of a rig limitation. If you want, please submit a bug.
Hi,Edward.
I think it's not bug, just the reversefoot component script in autorig is not fully tested with fkikblend.
The "t/r/s" input port of TransformObject is overriding "local" input port.
If you check the image above about rig logic,"lookat" subnet from reversefoot is overriding "fkikblend" subnet,so fk toe contorl is disabled.

I can use my own component script to create reversefoot,it's not hard to fix.I just think it might be better if beginners tring to create rigs only with autorig component would get a nice fkik setup.

Hi, This is a current limitation with the reverse foot setup as it is. The ikfk blend takes over the local control of the ball, removing all input parms. This is because the ikfk usually only deals with ik setups where no specific locals are affected.

To get around this however is very simple, we need to respect the parm inputs, so t, r, s and local of the transform object and instead reroute them to the ik helper for the ikfk blend.

Thanks for the input.
Edited by william_harley - July 18, 2025 12:05:05

Attachments:
electra_rig_example_reverse_foot_fix.hip (22.6 MB)
GIF 2025-07-18 17-52-28.gif (2.9 MB)

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Hi,thank you for the hip file,that's very clear and well explained.
I also noticed that you changed order of autorig component nodes.(the original file was "multiik--ikfkblend--reversefoot",now it's "multiik--reversefoot--ikfkblend")
I think this order could be important,and maybe confusing to beginners,so maybe put it in the documentation?

Anyway,thank you guys for listening,can't wait to animate in apex
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