SIMPLE joint bone rig

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muuvist
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SIMPLE joint bone rig

Post by muuvist » Sun Jun 29, 2008 9:43 am

This rig is obviously not as sophisticated as Vern's and it uses the old technique of 2 overlapping shapes but I thought that I would post it because it's so simple. I discovered it when trying to warp images. Please tell me if someone has posted it before:
The idea is to have 2 bones on 1 axis that move together with position constraints, the bone closest to the joint has no bone strength therefore doesn't distort the joint skin too much, here's a pic:

Image


Here's a link to a movie and the .anme file

http://muuvist.googlepages.com/simplejoint


EDIT, sorry still can't work out how to post images.
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synthsin75
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Post by synthsin75 » Sun Jun 29, 2008 10:09 am

Image

Here's your image Muuvist. I like it. Very elegant and simple solution. One change I'd make is if you parent the forearm control bone (3) to the arm bone (1) then the IK chain still works (i.e. the forearm can still move the upper arm).

I think this is my new standard joint. Thanks Muuvist! :wink:


::But it only works with flexible bone binding. That may be the catch. :?
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heyvern
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Post by heyvern » Sun Jun 29, 2008 10:53 am

It is much simpler than mine as far as bones. It does have more points though. I don't know if they are all needed of course.

Using flexible binding on the bone layer is a real problem for me though as synth mentioned. That arm bone is going to effect my ankle at some point. ;) I would like flexible binding if it could be used on a layer by layer basis rather than all the layers inside the bone layer.

There is still the issue of the elbow "getting smaller". The point at the elbow is still rotating too far causing it to lose volume. It should rotate "half" way between. That might be tweaked.

I really like this... but... I'm going to stick with mine until I can play with this concept. I think I might be able tweak this to work with region binding and fix the elbow... but it would require another bone I think.


-vern
funksmaname
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Post by funksmaname » Sun Jun 29, 2008 11:06 am

Hey there,

Cool idea but has some flaws -
1) IK is lost
2) the arm construction has a lot of what i would consider extrenuous points - but getting rid of them causes the rig not to work as well... simplifying the rigging at the expense of complicating the construction is imho like cutting off your nose to spite your face :)
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mkelley
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Post by mkelley » Sun Jun 29, 2008 2:00 pm

I was really excited about this... until I saw the bit about flexible binding.

As Vern says, it's a problem at some point in time. I often add props to my characters and flexible binding is going to screw them up big time no matter what I try. So I think I'll stick with Vern's rig for now (which isn't all that difficult to construct and can be simplified for legs which never bend backwards).

But thanks for sharing -- it's sharing ideas like this that make it better for everyone (because perhaps someone can improve upon this and make it something everyone can use).
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synthsin75
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Post by synthsin75 » Sun Jun 29, 2008 2:16 pm

Yeah, it'd be a good rig if you usually use a lot of point binding. I still can't figure out why flexible binding is the default setting. I always forget about it until something screwy starts to happen. :wink:
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Post by funksmaname » Sun Jun 29, 2008 2:25 pm

mkelley wrote:can be simplified for legs which never bend backwards).
an arm doesnt bend backwards either, but both directions of motion are necessary without having to flip the whole rig (you can flip the hand/foot at the central cross over point in order to make the arm/leg bend naturally in both directions! :)
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mkelley
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Post by mkelley » Sun Jun 29, 2008 2:40 pm

An arm doesn't bend backwards, but with a 3/4 rig you need to do it in order to give the illusion someone has raised their arm above their waist. You don't need to do this with legs (unless the character you are drawing can raise his leg above his waist :>).
muuvist
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Post by muuvist » Mon Jun 30, 2008 12:06 am

heyvern wrote: Using flexible binding on the bone layer is a real problem for me though as synth mentioned. That arm bone is going to effect my ankle at some point. ;) I would like flexible binding if it could be used on a layer by layer basis rather than all the layers inside the bone layer.

-vern
Yeah , you're right, but like I said I stumbled on it when trying to rig an image based character and all the arms and legs etc. are on separate layers. I used the technique in the forearm with one fan bone, take a look at this movie:


http://muuvist.googlepages.com/rabbit


I'll post the anime file but you'll probably have to re-link all the images. ASPRO should have some sort of "project" file system.
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synthsin75
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Post by synthsin75 » Mon Jun 30, 2008 1:08 am

Hey Muuvist, I relinked your images, but it's all distorted. If you relink the images from the same file you intend to share and save, AS will remember that path. (Images and AS file in same folder.)
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Post by muuvist » Mon Jun 30, 2008 2:46 am

synthsin75 wrote:Hey Muuvist, I relinked your images, but it's all distorted. If you relink the images from the same file you intend to share and save, AS will remember that path. (Images and AS file in same folder.)
Okay try the googlepages link again, it's called rabbit stuff 2 now. I left off the BG because it was big and not necessary.

EDIT: I think I screwed up again, I'll try to get it right later
Last edited by muuvist on Mon Jun 30, 2008 2:57 am, edited 1 time in total.
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heyvern
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Post by heyvern » Mon Jun 30, 2008 2:51 am

To handle links in AS files to keep them "local", always put the AS file "loose" in a project folder. Then put images, sounds, scripts in sub folders.

If the links go directly to a sub folder of the same folder that the AS file is in, the links stay local and will not break when zipping up for sharing.

Like this:

My Cool AS Project Folder
--> Scene1.anme
--> Scene2.anme
--> Scene3a.anme
--> Scene3b.anme
--> Images (folder)
------> Image1.png
------> Image2.png
------> Image3.png
--> Audio (folder)
------>Soundtrack1.wav
------>Soundtrack2.wav
------>Soundtrack3.wav

-vern
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synthsin75
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Post by synthsin75 » Mon Jun 30, 2008 2:55 am

Nice work Muuvist!
muuvist
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Post by muuvist » Mon Jun 30, 2008 3:07 am

synthsin75 wrote:Nice work Muuvist!
So you got it to work ok, that's good.

you can see that you can move the character quite a lot without too much distortion and it works well enough for an action scene, the soft edges on the pngs hide the overlaps fairly well
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heyvern
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Post by heyvern » Mon Jun 30, 2008 3:58 am

Ah yes!

This is a GREAT joint setup for image layers! Image layers only work well with flexible binding. Even I use it for that. No other choice.

For image work this is a good solution.

I liked the rabbit. reminded me of Watership Down... dang! Now I have to read that book again! ;)

-vern
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