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loked
04-24-2003, 04:23 PM
Hey,

Im busy reading up on some stuff about Gimbal Lock and I know this may sound kinda dumb, but I only realised now, that you only run into gimbal lock when rotating with gimbal. If you rotate with local or global, you dont run into this problem. Please correct me if Im wrong. Im really just assuming based on what I've read.

Anyway, my question is, what is the advantages of rotating with gimbal, why not just use local or global the whole time??

Sorry if I'm way off in any way. Thanks in advance!!

later
loked

dmcgrath
04-24-2003, 08:26 PM
Okay here is the long version. Don't worry, you just haven't had the experience yet.
Gimbal lock happens, even if you don't see it happening, it doesn't mean it isn't.
It is true that you don't notice if you use local rot or world rot options vs. gimbal. But if you switch back and forth between the two, you can tell exactly what is happening.
Okay, the advantages to using a gimbal based rotation are easy to notice. The rotations you get when the gimbal system begins to cross over each other happen this way. What you see is just x rotating (for example). Then when x has gone to a certain point, and you want to rotate just Y or Z. To get the arm to rotate where you want it to, in either of these directions, you will have to rotate BOTH values now. Many times it doesn't actually cause a problem, but many times it does. Some it will start to hang up even worse the closer Y and Z get to one another.

Nenox
04-26-2003, 01:07 PM
Hi Loked!


With "gimbal" you basically see what going on! If you like to work with F-curves or to key rotation axies independently, gimbal mode is in my humble opinion the only smart way to go, as your viewport manipulator actually shows what's going on and corresponds to what you see in the channel box and graph editor etc. If you always key all and don't use the graphs much.. maybe you would stick with local?!

A great thing with gimbal mode is that you quickly identify bad rotation orders as soon as you start moving limbs on a character! With clear information about how the axies behave you can easily judge when to change rotation orders (remember you can animate this parameter too) or when to insert an extra "Gimbal-fix-bone" into the hierarchy.

Although I mostly work in gimbal mode, I will occasionally switch to local to do the odd rotation instead of trying to nail it on multiple axies.

To sum this up, for the past 6 month I have been in a workspace with a quite a few people that have used the manipulator in local mode and where as I have never been caught by a gimballock - around me screams of frustration :scream:

So even though I don't know the math behind rotations and all, I can't really subscribe to your findings - Hope all this makes sense!


And oh.. Somebody please correct me if I'm wrong!

:) Cheers.

loked
04-26-2003, 02:19 PM
Hey Guys,

Thanx for the replies. I put up this thread at the general rigging section and got some good answers there as well.

I've got a pretty good idea about Gimbal now, so thanks to everybody that answered my question.

Later,

Loked

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