PDA

View Full Version : IK/FK blending - opinions wanted...

michaelb
06-16-2004, 02:02 AM
Hi,
I just noticed that Colin Cohen put a new plugin up on his Web site ( http://cohen-plugs.tripod.com/ ) called "FK Goals." Here is his description: "FK Goals, designed specifically for non-full-time IK usage, keys an FK rotation and snaps all goals of the IK chain back into place so that you can continue to use IK on the chain. When used in combination with IK Key, it becomes the foundation of a hybrid IK/FK system that will allow you to use IK and FK on the same set of bones on the same frame. To snap all the goals without creating an FK rotation key, turn off Key Current Object." It seems that this might be a new way to switch between IK and FK without having to use expressions or extra layers of bones in a character rig. Could someone who has more experience take a look at the way these two plugins function and compare them to a rig setup that uses three separate layers of bones (ex. http://www.lwhub.com/ikfk/ ) to give a similar effect? Wouldn't a setup that uses lots of expressions be harder to animate and slower in system response time? Then on the other hand, would layered bones and expressions give you more control in the long run? I would be curious to know what you think. I was wanting to construct a more versatile arm rig and if these new plugins work well, I might make them an important part of the whole setup.

Thanks,
Michael B.
adrencg
06-17-2004, 04:32 PM
I've been experimenting with those tools as well, and couldn't really see the point or get it to do anything. But I'm a dunce...

Maybe someone smarter than us could try this or maybe the plugin author could go into more detail on his site. There really is no documentation.

It looks promising, but I wouldn't expect much...I've learned over the years that when a Lightwave plugin seems to good to be true, there's a 98.5% chance it won't be. Unless it's HD_Instance.

It would be great if IKBooster worked in a way that was really usable as a character rig. That truly is IK/FK blending, but it's unruly as hell.

Mike
SplineGod
06-17-2004, 08:31 PM
First of all IK Booster does work in a way that is very useable for character animation. Im not having any problems with it here.

Ive also been using IKKey. This is a GREAT plugin. It actually makes part time IK in LW useful. Part time IK allows you to use IK for posing purposes and still allows FK to be used as well. The downside fo the way LW does it that is that you have to key all items making it cumbersome to go back and strip keyframes out of things that dont need it. IKKey only keys all the items that are part of the current IK chain (based on the selected goal).
This allows you to keep the rigs simple and yet have a great deal of control. Keeping the rig simple is important because it can slow down as you add expressions and other items onto the rig. :)
michaelb
06-18-2004, 11:46 PM
I've been experimenting with IK Key some more. It is a distinctly different way of working with IK. I'm not used to seeing the IK goals floating in one direction and the bones moving in another! I think I'll practice some more before I decide to include it on a permanent basis. I think I would get along faster if I had some kind of ghosting or onion skinning feature to help me place my goal positioning better. Or maybe it's just me. :rolleyes:
SplineGod
06-19-2004, 02:18 AM
If I use IK on the upperbody I definately would want to use IK/FK blending. Unless I needed the hand to stick to a surface I would only be using IK to rough pose the upperbody. I would then go back and use FK on top of the IK. I think its a great plugin. :)
michaelb
06-22-2004, 01:55 AM
Well, the more I play with IK Key, the more I like it. Darn if you're not right again, Larry. :) I hadn't noticed the fact that IK Key "...keys all the items that are part of the current IK chain..." until you mentioned it. I thought just the IK goals were being keyed and didn't see much advantage to using the plugin until you made that comment. Thanks for the insight. Turning full-time IK on and off on the fly and retaining the motion is a cool experience. Looks like IK Key will earn a respectable place in my setups. Less expressions to learn, too. :)
CGTalk Moderation
01-18-2006, 11:00 AM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.