Moho Forum

How do I ?
I have a character facing the camera I want to make him point at some thing behind him with his thumb. How do I make his arm appear to be going forward and backward?
Thanks.

Do some sketches on paper for the key positions, decide how strong the perspective will be and where to switch elements. Then open Moho.

Maybe this will give you some ideas?





A few notes about what's going on in each version...

- A Switch layer is used to change the hand drawings. There are four drawings:
1. Fist front
2. Thumb up front
3. Thumb up knuckles
4. Thumb up back

- Animated Layer order sends the left arm behind the body

- Animated Shape order is used to move the right lower arm from front to back. this is noticeable in the second version.

- Color transparency is used to hide and reveal the short line segments in the shoulder

- The main difference between version one and two is in how the lower arm swings. in the first one, the arm rotate upward until the forearm overlaps the upper arm, and then it's counter rotated for 355 or so degrees in one frame. This trick makes the inside rotation appear to carry through. In the second one, the arm is rotated outward, which is more cartoony and simpler to animate. I don't think one is better than the other, they're just two different ways to convey the same message.

I didn't bother with Smart Bone Actions for the above but you can add them if the rig needs to be re-used for other animations.

Here are the Moho files for you to study: ThumbsUpGuy.zip

They're in Moho 13.5.1 format but they should be compatible with 12.5.

Hope this helps. Feel free to ask questions.

Additional tip: Naturally, you will need to adjust the second half of the animation if he needs to point directly at something behind him. This might require foreshortening the hand drawing a little, but I don't recommend going too far with that because you may lose the readability of the 'thumbs up' gesture. If necessary, it might help to reframe the position of the object he's pointing at.

Another tip: I kinda just winged it for the above demonstration, but normally I would act this motion out to make sure I understood the mechanics of the motion. Your own body (or another person in the room) can be great reference for this sort of thing.

Big thank you to All who replied or read my post.
Lots of productive help.
As usual I appreciate it very much and thank you for your time you gave to me by answering.
Bob

Oh, and a +1 for slowtiger's suggestion to sketch out the key poses. No animation is too short that it shouldn't be storyboarded.

Here's another take I made during my lunch break...



This one features a more direct pointing motion. What's different here is I added a slightly foreshortened hand that points backward, and to make it appear to move forward/backward in z-space, as described in the original request, I'm shortening the forearm bone as it rotates 'toward camera'. It's a subtle trick but I think it works.

Try exaggerating the effect to see how far you can push it. Here's the file: ThumbsUpGuy03.moho

Edit: I updated the file by adding just a touch of scaling as the hand moves backward. To do this easily, you need to move the hand Switch layer's origin over the hand bone's pivot point.

@ Greenlaw:
slightly foreshortened hand that points backward, and to make it appear to move forward/backward in z-space,
shortening the forearm bone as it rotates 'toward camera'.
Yes after some tests this is what I went with. Good old mirrors they're an animators friend.

Thanks again.

The art of staging (or blocking) is two-fold: firstly it serves the drama - how to tell the story in the best way. But the second purpose is, in my opinion, much more important on a scene-by-scene level: how to avoid angles and poses which are not readable, hard to draw, and slow down production unnecessarily.

I've noticed that many animators (inculding myself) tend to neglect No. 2, at least occasionally. We like to show off, we like to make something impossible work, we like to stretch the abilities of our rigs, our software, everything. Sometimes the result justifies the amount of work, but very often it does not.

@slowtiger:
Sound advice and I thank you. I have a weird way of basically storyboarding my song animations, but it works for my basic idea,