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mouseman

Rigging from P.I.

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Have you seen the Pigeon Impossible video? More relevantly, have you seen the PI blog videos? There are a couple on rigging which might give you some ideas (episodes 9, 10, maybe part of 11), even though it's made in XSI.

 

http://www.youtube.com/view_play_list?p=19E7DC81F6D1D522

 

I can't remember which episode it was in, but there was also a rigging trick that prevents legs from snapping when the IK controller reaches its maximum length.

 

Chris

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The one trick that I really thought was neat was the last trick on this video:

 

#17 - Pigeon Rig

 

Watching one of Robcat's tutorial videos on walking, he had a bit of problem with the Tin Woodsman and his legs popping; if even someone as experienced as robcat has these problems, then surely I will too! In the pigeon video, Lucas does it by making the leg bones bent slightly (even though the model is modeled straight up and down). I don't quite understand how the IK limits works in this instance, but the behavior he demos is quite nice. Would that trick be applicable to the squetchy or 2008 rig (or lite rig, etc)?

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The one trick that I really thought was neat was the last trick on this video:

 

#17 - Pigeon Rig

 

Watching one of Robcat's tutorial videos on walking, he had a bit of problem with the Tin Woodsman and his legs popping; if even someone as experienced as robcat has these problems, then surely I will too! In the pigeon video, Lucas does it by making the leg bones bent slightly (even though the model is modeled straight up and down). I don't quite understand how the IK limits works in this instance, but the behavior he demos is quite nice. Would that trick be applicable to the squetchy or 2008 rig (or lite rig, etc)?

 

The solution in Lucas' tutorial would have to be modified for the Squetch Rig...it would take a little thinking, but I'm sure it could be done. The problem comes in when you squash or stretch an arm or leg...the geometry bones would have to be kept straight and centered or the squetching will be wrong, so they can't be in the same location as the bent control bones. I'll do some thinking, there may be a few solutions to the problem.

 

I'm pretty deep into a tail rig upgrade at the moment, but I'll mess with the arms and legs in the Squetch Rig when I get a chance.

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The one trick that I really thought was neat was the last trick on this video: [...] Lucas does it by making the leg bones bent slightly (even though the model is modeled straight up and down). I don't quite understand how the IK limits works in this instance, but the behavior he demos is quite nice. Would that trick be applicable to the squetchy or 2008 rig (or lite rig, etc)?

The solution in Lucas' tutorial would have to be modified for the Squetch Rig...it would take a little thinking, but I'm sure it could be done. The problem comes in when you squash or stretch an arm or leg...the geometry bones would have to be kept straight and centered or the squetching will be wrong, so they can't be in the same location as the bent control bones. I'll do some thinking, there may be a few solutions to the problem.

 

I'm pretty deep into a tail rig upgrade at the moment, but I'll mess with the arms and legs in the Squetch Rig when I get a chance.

 

I assume you haven't had an opportunity to look into this. However, it sounds to me like there is a conflict with the geometry bones, which can't be kept straight for Lucas's solution, but have to be kept straight for squetching. Maybe the squetching can be done on some control bones, and the geometry bones linked (with compensate) to those control bones?

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The one trick that I really thought was neat was the last trick on this video: [...] Lucas does it by making the leg bones bent slightly (even though the model is modeled straight up and down). I don't quite understand how the IK limits works in this instance, but the behavior he demos is quite nice. Would that trick be applicable to the squetchy or 2008 rig (or lite rig, etc)?

The solution in Lucas' tutorial would have to be modified for the Squetch Rig...it would take a little thinking, but I'm sure it could be done. The problem comes in when you squash or stretch an arm or leg...the geometry bones would have to be kept straight and centered or the squetching will be wrong, so they can't be in the same location as the bent control bones. I'll do some thinking, there may be a few solutions to the problem.

 

I'm pretty deep into a tail rig upgrade at the moment, but I'll mess with the arms and legs in the Squetch Rig when I get a chance.

 

I assume you haven't had an opportunity to look into this. However, it sounds to me like there is a conflict with the geometry bones, which can't be kept straight for Lucas's solution, but have to be kept straight for squetching. Maybe the squetching can be done on some control bones, and the geometry bones linked (with compensate) to those control bones?

 

I haven't had time to work on a complete solution yet...I have a partial solution. I'm still working through some issues with the tail rig, so I haven't been able to concentrate on this problem. There are a lot of things going on in the Squetch Rig that will be affected depending on the changes...the geometry bones and the control bones are going to be two separate problems. I'm sure it can be done, I just haven't gotten to it yet.

 

If you have a ready-made solution, feel free to do some testing. Be sure to exclude any compensates that would need to be reset during installation...there won't be any in the next release. In case you need something to refer to in your testing, there are a couple of videos here and here showing how the limbs should work.

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I took a short break from working on the tail rig and worked on the arm setup. There are at least three solutions that I know would give you a soft IK, never completely straightening the IK chain (Lucas' solution), resizing the bones as the chain bends or delaying the end target.

 

Lucas' solution would cause problems when squashing and stretching and the resizing bones solution would have been too extreme if it were to completely compensate, so the winner in my mind is delaying the end target...that also allows for bending the arm/leg backwards in IK.

 

I posted a couple of clips showing where I'm at here.

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This looks interesting ,so it don't fully strighten with the soft one on ,but it looks allmost striaght and stops the click ,thats good and would be very usefull

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This looks interesting ,so it don't fully strighten with the soft one on ,but it looks allmost striaght and stops the click ,thats good and would be very usefull

 

If you move the null far enough, it will straighten, but you'll get a slight pop in the last degree or so if you do it that way. The Expression uses an equation for exponential decay, so it slows at the rate necessary to prevent the "pop".

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A biped Squetch Rig update is posted here...it now has soft IK on the limbs. Thanks for getting me to look into that, Chris!

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