View Full Version : IK Booster: Binds and Bakes

Ramen Sama
10-05-2009, 07:29 PM
I'm going nuts here. I've been learning all there is about IK Booster for posing and it's great.

But now i've moved on to actually animating.

I'm having issues with the feet moving around and under the ground plane. I know this has to do with binding and or bakespots, but i can't figure it out.

Lets say we have a human, and they sqaut down. 2 frames, one standing up, the other squatting down. Everything looks fine on the first frame, everything is fine on the last frame, but the inbetween frames is the problem.

The feet will move down below the ground plane, then back up. I'm sure anyone who's animated with IKB knows what i'm talking about.

I've had some success doing binding/baking, but it only seems to work on one foot, then when i move to the other, it undos what i did to the other.

I can't get both feet to stay put like they should. Is there any real documentation and/or tutorials that can help me make sense of this?

10-05-2009, 07:53 PM
I'm sure SplineGod or someone else can help you with IK booster bake/bind. But from my experiences with IKB they are not worth the trouble for feet.

Set up standard IK for limbs that are in constant contact with a stationary surfaces. Your life will be a lot easier!

10-05-2009, 08:18 PM
Anyone who's animated in a 3D package knows what you are talking about. Don't worry, its supposed to happen like that. (Well, not supposed to, but it does in every program, there are ways to cope, like this...)

So, set your keyframes so that you have perfect motion. If you play the animation, you are going to get the weird movement (below the floor, through an arm or leg, whatever). But make sure you have the keys in the proper positions.

Now, when you are sure everything is right. Select the bones that move (the feet), set them to the proper position, and use the BIND command. Now, when you run through the motion, they will not move. This is the work flow. Set the keys, make sure they are okay, THEN use bind to put the extraneous movement in place.

(At least I think its bind... )


10-06-2009, 01:21 AM
I find that the opposite to be true...its worth dealing with them to get all the extra goodies that you cant do or cant do easily with the standard tools.

Binding assumes that the extremety is moving and the root is not. For example a character walking in place. When you bind a foot using a bakespot the foot will stay locked exactly where its at for the duration of the bakespot and move the root(characters body) forward.

Baking assumes that the root is moving and you wish to lock the extremety.
For example a character was animated walking in place and now you move the root forward. Theres a bit of slippage on the feet so you can again use a bakespot (or not) and this will lock the extremety in that spot for the duration you specified while the root is still moving. This is useful for things like a character walking along and grabs a sign. His hand/arm will stay locked to that sign for the duration you specified.

Usually what I do is to refine my animations and when Im down to animating on 3s etc I will bake or bind to finalize...in other words do it last because you never know if you need to tweak things.

Ramen Sama
10-06-2009, 11:40 AM
well i've learned a few things since i posted. It seems you can only bind one item per frame range. This might explain why something will work on one foot, then i'll bind the other foot and loose it's positioning. I noticed i can't multi select and have bind work like i'd expect.

Besides making keyframes when you tell it bake, what does the bakespot do? do it help manage something behind the scenes?

10-06-2009, 05:06 PM
Binding does only work on one thing at a time. You can multiselect and Bake though.
If you create a walk cycle of 40 frames. You would actually set bakespots on the contact points of the foot. So for a few frames it would be the heel, then the ball of the foot and so on. Now you can copy the keyframes out to extend the walk cycle to 400 frames. This will also copy the bakespots. Now if you use Autobind the character will now walk forward automatically for all 400 frames.

If you were animating using goal objects and standard IK you would have to use the graph editor to make sure that at each point the foot needed to stay locked without any drift you would h ave to make the keyframes linear on the goals for the duration that the foot stays in contact with the ground. Doing all that can become pretty tedious.

The bakespots can be created as you go and tweaked later. They sort of remind you that at some point you either have to bind or bake. Once youre ready you can use the rebind all or rebake all command.

10-06-2009, 05:31 PM
To be honest adjusting keyframes tangents is a small price to pay. For the ability to repose your character in real-time. A good animation is largely illustrated in the weight and balance of the character main body line. If you need to re-bake every time you want to change the line of the character. Your wasting an animators time. I don't mind the idea of bake and bind for some elements. But for feet it is just not wise. It takes so little effect to setup a proper leg with IK, It just simply out weights the work needed to manage your keyframes with IK Booster. I would just never make a rig for an animator that way.

10-06-2009, 05:43 PM
Part of it depends on your particular workflow. I dont usually lock things down until Im ready to finalize the animation because I dont want to spend alot of time undoing the tangents and redoing them.
Its actually quite easy with IKB to repose and rebake and I dont have to leave the interface to go into the graph editor to futz around. Its also quite easy to slide the timing for the baked items as well. Having used both methods in LW Ive found IKB to still overall be much faster for me. :)

10-06-2009, 07:51 PM
If your in the early stage of animation you using step keys. So there are no tangent to edit. Later when you're editing TCB to lock a keyframe in place you don't re-edit them often. Unless you are editing the speed of the incoming or outgoing animation. You can even do it without entering the Graph editor. With the Move TCB tool under the modify tab. Click the left and the right mouse button to control tension and bias. You can watch the motion path change right before your eye for Instance feedback.

Or for even more control you should have a leg with FK/IK blending legs. This would allow you to always use step keys for the IK and simply use FK whenever it's not in contact with a world space object. Best of both worlds without baking.

Ramen Sama
10-07-2009, 02:24 PM
I'm leaning towards going with traditional IK for the legs even though i really like the posing aspect of IKBoost.

I'm not liking this binding process. I was able to get both feet to stay in place while squatting, but the origin of the object won't go down strait. It goes down and to the left or right then towards the center.

I've yet to get the feet to remain in place and have the body move down strait like i'd need it to.

04-26-2010, 01:36 PM
expressions can keep the feet above ground generally - if i put an expression on that tracks the spine's root angular motion - which is dipping to the left or right causing the foot to go thru the floor i can eliminate most key by key corrections - i can't just use the foots position because its relative to the farther-up-items in the bone skeleton and stays at zero. i check where the spine is, when the foot goes under and apply the expression accordingly when the spine is less than or greater than...

04-26-2010, 02:17 PM
For things that need to stick and pivot (Hands OR Feet) it is a lot more fun to animate with a simple IK chain and a pole item for the knees and elbows. I'm sure somebody already said this to you but I would just like to back that idea up for someone who has trouble otherwise. You can apply IKB on top. I have some short videos on that if you are interested.



04-26-2010, 03:57 PM
Regular rig with IKB on top. That's the intended purpose.
So, a sticky-feet rig with Ik arms and maybe one of Poobys IK spline spines, then lay IKB on top of all that would be the best rig of them all? Or so I'm left to understand.
Maestro rigs are kind of cool and fun for this purpose.

04-26-2010, 06:12 PM
Yeah, Im not a fan of doing actual hand animation with IKB either...

its allw ell and good to just leave the baking/binding/whatever till later in the game... but that kinda defeats your ability to see things working properly from the getgo... so then ur back to redoing bakes and binds everytime you want to tweak positions, or timings, etc...

What a headache...

IKB is great as an animation editing tool... retiming whole animations, adjusting mocap, copying set animation clips between characters/times, and the like... its kinda like a "motionbuilder-lite" right inside LW to that extent, which is great... but for straight up hand keyed work, it sucks.

Straight rigs all the way I say.

There are of course variations... cehck out the fun with IKB in 9.6 thread in the CA sub forum, which uses regular rig, with IKB used to pose and animate the actual goal nulls, and FK sections of the character.

04-26-2010, 07:24 PM
baking and binding is something I do when finalizing the animation. The last thing I do regardless of how Im doing it is to do the final absolute locking down of things.
Its not too different going to the graph editor with IKGoals to change the in and out keys to linear or setting the tension to 1.
If you change the animation after locking those down they have to be undone changed and redone.
IKB has tools for tweaking things even after theyve been baked or bound. Its something that has never caused me much in the way of problems.
I also tend to save motion clips on a regular basis as a way to go back to previous animation settings. Its pretty quick to do.