The Model Bone

[guye]

Hello, when does one animate the model bone in a choreography?. say a character spins on his heels, would that be the model bone doing the main rotation and the bones making it look real or..?

 

i dont like the idea of 'leaving the model bone behind' when the animating just the bones, however whatever constraints are on the model seem to become less than useful if the model bone is used to move from a to b (not including paths here)

anyway am mighty confused about this. and what about a somersault. ? or blocking out a scene.

 

 

[pixelplucker]

Model bone is the center of the object based on 0,0,0 in the model window. It is just a means of grabbing the object in the choreograph mode (f9). Most characters have base of feet at 0.0.0. This doesn't effect the balance of the character because the skeleton and balance rigs take care of that.

 

For character models you should rig them either manually or use one of the stock skeletons or in the 32bit version of AM you can use TSM2 (The setup machine, which makes it easy to rig characters that are not bipeds or don't have an existing skeleton).

 

When I first started I followed the tutorials from The Art of Animation Master. I picked up the books on it but I believe there are online versions here somewheres on the forums.

[robcat2075]

Welcome to A:M, guye!

 

Hello, when does one animate the model bone in a choreography?. say a character spins on his heels, would that be the model bone doing the main rotation and the bones making it look real or..?

 

i dont like the idea of 'leaving the model bone behind' when the animating just the bones,

 

 

 

I also was worried about leaving the model bone in one spot and having a character walk away from it when I started animating but that is the overwhelming choice among animators professional or otherwise.

 

The model bone is good for moving the entire model as a whole but that is something animators rarely do. They are always moving parts in relation to other parts. Even when the whole body is in motion, it never moves as a rigid whole which is the effect of moving the model bone.

 

Here is a step-thru of an old back flip I did. The model bone is never moved, but all the other bones are animated to turn the character 360°

 

In this view bones turn red when they have a key frame on them.

 

clip3568Gymnast.mov

 

Basically, you key bones as often as you need to to get them where they need to be.

 

 

 

however whatever constraints are on the model seem to become less than useful if the model bone is used to move from a to b (not including paths here)

anyway am mighty confused about this. and what about a somersault. ? or blocking out a scene.

 

 

I'd have to know more about the constraint problem. Constraints should work no matter where the model bone is. This suggests some additional mishap you may want to tell us more about.

[guye]

thanks thats helpful, actions on paths then from a to b.

 

so basically in a big screen animation most of the main movement around a scene will be characters on paths?

there'd be one main entrance/exit path and all the jumping around,scratching the butt and gesticulating would be away from that path.

 

like for instance 'character(walks into room) constrained to path until frame.. then unconstrained,moves to the left a few metres, scratches butt, does a quick twirl, and then back to path, constrained back to path, walks off screen.? throughout which the model bone is not touched.

 

 

 

 

 

 

[robcat2075]

thanks thats helpful, actions on paths then from a to b.

 

so basically in a big screen animation most of the main movement around a scene will be characters on paths?...

 

Nope. Paths, as we know them in A:M, are rarely used in character animation. The model bone is placed once to locate the character at the start of the scene in some convenient spot, but after that the skeleton bones of the character are animated tp create whatever motion is needed.

 

Here's a video that shows the animation process on a simple robot. Notice that even though the robot is being animated to walk forward the model bone is never moved.

 

Post #20 Simple IK Leg Walk.

 

If all a character had to do was walk the same walk indefinitely, then we would use a walk cycle on the character with the model bone constrained to a path. However it is exceedingly rare in story-telling situations for a character to just walk. When they also have to do the butt-scratching and twirling, getting in and out of that path constraint is a huge hassle and it's really easier to keyframe all motion from start to finish.

[robcat2075]

P.S.

 

My animation of the backflip WAS done in an Action instead of the Chor because I did intend to repeat it exactly a few times and animating that once in an action, then reusing it in the chor made that easier. A rare case.

 

None-the-less, the model bone isn't moved to make the character flip, it's all skeleton animation. (It's actually impossible to move the model bone in an Action. You can only keyframe a model bone in the Chor.)

[guye]

thx robcat . ure tutorials r great btw. been watching them over the last week or so, never saw the ik walk one tho, thx for sharing

[Clipping Path Specialists]

Your tutorial is good.