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Lottmedia
09-30-2008, 01:01 PM
what is it and how shoudl it be used?

C :cat:

flakester
09-30-2008, 01:07 PM
Used to be known [and still is, in some cases] as 'Up Vector'.

It can be used to help keep elbows and knees pointing in the right direction in IK rigs. Well, that's one of it's uses. Basically helps with targeting and orientation.

How you implement it depends on your setup from what I have learned so far.... which is on a mechanical linkage.

Use a null ubject as your 'pole' [hoo-hoo-fnarr-fnarr] and tell parts of your rig [or linkage] to use it as the pole item in the object's motion properties.

Hope that helps,

flakester.

Lottmedia
09-30-2008, 01:16 PM
I originally saw it in the results of a Make Joint Chain, It worked well and I likes that you could point the knee with it. I was looking to figure out how to do silimar with regular bones (because joint bones seem not to work so well for some reason) but when I use it it seems to have too much coltrol over the rig and pulls like a goal.


C :cat:

flakester
09-30-2008, 01:56 PM
Yeah, they tend to do that in most cases. In the 9.5 "What's New" docs, they talk of using them in conjunction with targets [I think]. Not had enough experience with the poles in 9.5 to know anything definitive.

The best way round that wee niggle that I have found in previous applications, is to make the pole items children of a non-critical part of the entire hierarchy ~ such as the root null or bone...... so that they get to carry the overall motion of the rig, but don't get thrown about wildly by limb kinematics or other objects.

This way, you can animate them in relation to the rig. It can help in adding very useful nuance motion.

I'm actually itching to get to grips with the 9.5 bone systems and poles - just need a bit more time!

flakester.

ercaxus
09-30-2008, 02:32 PM
I originally saw it in the results of a Make Joint Chain, It worked well and I likes that you could point the knee with it. I was looking to figure out how to do silimar with regular bones (because joint bones seem not to work so well for some reason) but when I use it it seems to have too much coltrol over the rig and pulls like a goal.


C :cat:

1 - make a chain and setup your ik.
2 - add a bone to the chain at the same position with the first bone
3 - parent the chain to this new bone.
4 - target this parent bone to the ik goal of the chain (at this point you can rotate the ik chain using this bone's bank rotation but we want to make it automatic)
5 - add a null and move it in front of knee/elbow or equivalent part of the chain. this is the pole control
6 - for the parent bone select the last null as pole item.

If you do the step 4 using ik instead of target you can switch ik/fk a little easier.