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JaredTaylor
11-03-2011, 02:28 AM
Hi,

I have been stumped on something really simple for a while, and I have no idea what the cause is. I've setup a spine, and made it stretch and squash, but when it stretches or squashes it doesn't stay with the chest controller. It looks like it's scaling twice as much as it should.

If I make a new scene and make the same setup, it works fine. I've remade this setup twice and dumbed it down as much as possible but nothing is making itself apparent as to the cause.

I'm getting really frustrated because it will be something silly that I've overlooked, but I can't find what it is.

Do you guys ever get this type of issue in general, where you can't find something easy, yet you've done really hard stuff before? >.<

Here's the rig if anyone is willing to take a look... cheers.

http://localhostr.com/file/0uBsTuI/squirrelRig_spineStretchIssue.zip

Boucha
11-03-2011, 05:06 AM
Hi There,

I wonder why you have created conditional and color blender nodes (seems to be creating scale issue) to create the stretchyness! You can simply connect the output of multiplyDivide (spineStr_MD) node to the scaleX of spine joints.

JaredTaylor
11-03-2011, 05:33 AM
Hi there,

That color blend node is important; it lets me make an on/off switch. The condition is just how i've always done it (probably because it's necessary to prevent squash in leg setups) but taking them both out doesn't solve the issue :(

Boucha
11-03-2011, 06:51 AM
Hi, Seems like the problem is created by the joint hierarchy. Try breaking all the connection from all the spine joint and connect the output of blendcolor to the scale X of the root joint! (hip_JNT) ... It should work :)

JaredTaylor
11-03-2011, 07:00 AM
Hi,

I'm a little confused... if I did that, only the hip joint would scale?.. or am I misreading what you're saying?

Cheers

Boucha
11-03-2011, 07:52 AM
Yup it will scale the hip joint and all the child joints in it's hierarchy inheriting the transformation from the parent joint.

fer-noo-noo
11-03-2011, 11:09 AM
It's because you lost or broken your scale-inverse scale connections between spineA_JNT and spineB_JNT and also spineC_JNT and spineD_JNT. Just go to connection editor and reconnect and it should all work fine.

JaredTaylor
11-03-2011, 06:09 PM
Hi there,

Unfortunately that only scales the hip joint. The hierarchy is quite normal and they all need to be connected for it to work. Even with just the joints, the ikhandle and the curve, it still has the problem. This is an identical setup that I've used on other rigs without the issue, I can't work out why it would be doing this.

JaredTaylor
11-04-2011, 03:36 AM
Still need help... :(

Boucha
11-04-2011, 05:21 AM
hi there, try recreating the same exact setup again. For some strange reason the connection on joint scale is overriding the overall scale of the joint chain and thus the double transform. Try setting up the spine in a new scene file :)

JaredTaylor
11-04-2011, 07:08 AM
Hiya,

You solved it! Just importing everything into a new scene worked. I didn't imagine it'd be a bug with the scene itself, that was really weird.

Thanks so much :)

Boucha
11-04-2011, 11:01 AM
Yup sometime importing or starting all over helps! :D

fer-noo-noo
11-08-2011, 01:12 PM
Hi,

The problem was your scale/inverse scale between your joints was disconnected which was causing a double transform on your joints.

I looked at the scene and the disconnection was between joints A and B and also C and D.

I did post this earler but for some reason it didn't post!?!?

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11-08-2011, 01:12 PM
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