Houdini kinefx ikfk switching
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- zf3d
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- SWest
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Hi, I went down this rabbit hole, and got something barely working. However, I'd not recommend spending time with this unless you really think it is worth spending days troubleshooting Python code (or some other method, if possible).
Simply using a blend node between FK and IK should please most animators, or no? Is there a very important reason why you would like to do this?
However, maybe there is no single tutorial that actually show this. To get anything done with my code it was a lot of research to say the least, and it is still quite "hard coded". I estimate it took about 23 days (based on my file history) with anything from 5 min to hours of research and testing (only very limited free time). Prior to that I had already solved this with Blender (some years ago). I added a demo of the current state so you can check. It works in Houdini 19.0, but not in 19.5.
Now, updating this so it works with Houdini 19.5 and then for arms and legs with different characters would take probably a month or so. There are other things more important IMHO.
Simply using a blend node between FK and IK should please most animators, or no? Is there a very important reason why you would like to do this?
However, maybe there is no single tutorial that actually show this. To get anything done with my code it was a lot of research to say the least, and it is still quite "hard coded". I estimate it took about 23 days (based on my file history) with anything from 5 min to hours of research and testing (only very limited free time). Prior to that I had already solved this with Blender (some years ago). I added a demo of the current state so you can check. It works in Houdini 19.0, but not in 19.5.
Now, updating this so it works with Houdini 19.5 and then for arms and legs with different characters would take probably a month or so. There are other things more important IMHO.
Edited by SWest - Nov. 17, 2022 14:51:21
Interested in character concepts, modeling, rigging, and animation. Related tool dev with Py and VEX.
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- made-by-geoff
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Ugggh. I went down this same rabbit hole. It's a bear. I didn't find any way to approach this like you are used to in other apps without extensive Python scripting that went beyond my capabilities.
That said, if you have the flexibility, it's worth re-think what it is you are trying to accomplish and whether there isn't an easier way given the strengths of KineFX. Part of the reason we need FK/IK switching is because we're used to the idea of working with a single rig at a time. But KineFX makes that way of thinking less necessary.
Why not have an IK rig, do what you need to do with it, and then append a set of FK controls afterwards for fine-tuning? That may not be exactly what you are trying to do, but my point is that KineFX has made me think about rigging differently: as a series of rigging layers, instead of a single rig that has to match FK and IK, if that makes sense. And as SWest says, there's also lots of ways to use blend nodes to blend between IK and FK rigs.
Post some more specifics of what you're trying to do and we can try to find a solution.
That said, if you have the flexibility, it's worth re-think what it is you are trying to accomplish and whether there isn't an easier way given the strengths of KineFX. Part of the reason we need FK/IK switching is because we're used to the idea of working with a single rig at a time. But KineFX makes that way of thinking less necessary.
Why not have an IK rig, do what you need to do with it, and then append a set of FK controls afterwards for fine-tuning? That may not be exactly what you are trying to do, but my point is that KineFX has made me think about rigging differently: as a series of rigging layers, instead of a single rig that has to match FK and IK, if that makes sense. And as SWest says, there's also lots of ways to use blend nodes to blend between IK and FK rigs.
Post some more specifics of what you're trying to do and we can try to find a solution.
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