View Full Version : Rig works well... until I set keyframes

07 July 2012, 03:00 AM

I was trying out a new method for doing facial rigging and have run into a problem. What I did, was envelope nulls to my model and then use "link with" to create shapes to connect to sliders. I saved each shape as an action and imported it into the mixer. Now I can use the sliders to drive all the shapes.

As long as there is no keyframe information on the sliders, the rig works great. However, if I start setting keys on the sliders, the rig stops responding!!!

I have uploaded my scene here:

You can find the sliders in a custom property panel under the head control. Would appreciate any help you can give me. Thanks!

07 July 2012, 06:24 PM
I'm not much of a rigger but at a glance I would say that you are layering improperly. If You are trying to define shapes with the weighted nulls then trying to animate them on top of that it won't work. You could have another layer of nulls that do this though. Essentially layer a 3rd set of nulls in on top and weight those instead, so the lower layer moves the nulls into the shape but you still have a layer of un-linked nulls to hand key.

I dunno if any of that made sense.

07 July 2012, 08:56 PM
Actually I just want to use the nulls to make the shapes and then animate the sliders. After making the shapes, I would hide the nulls and not even look at them.

I wanted to do it this way bc making shapes with enveloped nulls is much easier for me than shape modeling.


07 July 2012, 02:32 AM
Hrmm, this is a tough one cus then yeah I'm way off... I looked at the scene, I think the issue is with overlap on the link with setup. I think once it layers a key onto one of the sliders it locks the axis associated with that link to the animation. You may need to replace the links with expressions or scripted operators. That said the shape solution would still probably be easier.

If Shape building is an issue you could simplify it by converting an edge loop to a curve and doing your shapes just on the curve, then constrain the nulls to points on the curve and weight them like you've already done. You'd still have to build the shapes on the curve but it would be very similar to what you have now without the confusion and problems of the link with.

07 July 2012, 05:14 AM
Thanks for the reply. I'm bummed to say this, but I think you may be right. I'm surprised to see that this technique doesn't work though bc Manny Papamanos shows it on his 3d mastermind rigging videos. He never shows himself setting keys/animating his rig, but he definitely rigs a few mouth shapes using link with and the mixer. Ah well...

Do you know if it's possible to save the poses I made as shapes, even though the deformation is from enveloped nulls? I've been looking for a way to do it and haven't been able to figure it out. Just selecting the mesh and hitting store shape isn't working.

I'm also wondering if I can keep the geometry separate (head, teeth, gums) or if I have to merge them into one item... The reason why I ask is bc the shape manager only seems to show one item at a time.


07 July 2012, 05:32 AM
This setup is not really a valid one in my eyes. If you're going to make a rig that has objects that are used in an envelope deformer, then they should have controls. If your aim is to just create blend shapes, make blend shapes.

You can use this setup to create your blend shapes then once you're happy with the blend shapes then delete the rig used to create them (save a scene version with it still setup) and just leave the other overall controls.

The shape manager is useless and breaks / gets locked out because of the simplest things. Use an ICE based setup instead which gives you a huge amount of flexibility and customization.

If you still want to have controls that ride on top of the blend shapes, setup the tweaker controls using Steven Caron's dorito method. He does a great job explaining it in the XSI Blog article. This setup can be done in ICE as well if you know enough to translate it though I'm not sure rig performance wise it would be better.

07 July 2012, 07:44 AM
I figured out how to do it. I make a pose animation, save it as an action, then use an expression to make a slider drive the action's weight.

Thx for all the replies!

CGTalk Moderation
07 July 2012, 07:45 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.