Stroke shape arms with sleeves!

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heyvern
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Stroke shape arms with sleeves!

Post by heyvern »

Image

I don't remember the first person to come up with the idea of using stroke shapes for arms and legs but I am really starting to like it! Whoever you are THANK YOU! It really is a freaking awesome trick. With features like smart bones, stroke exposure and follow path you can do some amazing stuff.

For this character I originally created everything the way I always do with filled shapes for arms. As we all know you need to do a lot of tricky stuff to get the joints to bend nicely, smart bones, extra bones etc. Then I tried to animate a simple thing like rolling up his sleeves. Freaking nightmare with filled shapes. Getting everything to line up.

I kept looking at the style I was using and thought, this would be a great time to use stroke shapes for arms. The character is very simple, with a simple shading effect. Arm bending would be a breeze with smart bones. The arm only has 3 points. Just two end points and one point at the elbow.

For the rolling up the sleeve efffect, the trick was to combine 3 features of Anime Studio:
Smart Bones
Stroke Exposure
Follow Path

Arm and Sleeves
Stroke exposure works based on the initial direction the vector is drawn. To do the sleeve rolling up the way I wanted I had to "reverse" the direction of the vectors drawn, so that the arm stroke exposure is based at the shoulder, and the sleeve is based at the wrist. When the sleeve goes up, the arm shape stroke exposure increases, the sleeve stroke exposure decreases.

The next tricky part is the sleeve cuff. How to pull that off?
(I printed out the Anime Studio documentation and placed it under my pillow while I slept. The next morning I had a brainstorm! ;) )

I drew the cuff of the sleeve on a separate layer. I assigned a "follow path" to the arm stroke and set the layer properties to rotate to follow path. I adjusted the initial follow path setting so it lined up with the exposed arm shape. The arm shape has round end caps and it stops just inside the black inner shape of the sleeve cuff, making it look like the arm is "inside" the sleeve.

Next was the smart bones. I created a single smart bone for each arm with two actions.
The sleeve starting or default position is a little bit more than half way down. Just past the elbow.
The first action pulls the sleeve down to the wrist, the second goes up to the shoulder.

In each action I adjusted the stroke exposure for the arm and sleeves so they match up. This lined up perfectly because both strokes were identical in length and always stayed lined up.
Next I adjusted the follow path setting for the sleeve cuff so it followed the arm path as the sleeve moves up and down the arm.
The next step was to modify the sleeve cuff during the smart action so that it appears to change in bulk as the sleeve moves up and down the arm. The illusion is perfect.
I then created a smart bone action for the forearm bone and decreased the curvature of the arm at the elbow point.

The only extra tricky effort was masking the TOP part of the sleeve stroke where it joins the shoulder. I didn't want a simple flat end, or a perfectly round end cap. I needed the top of the sleeve shape to appear as part of the rest of the jacket. BUT... I also needed the arm shape to be able to change layer order, go behind or in front of the body.

I put each arm group of layers (hand, arm, sleeve) into its own group inside the bone layer. I set the group masking to "reveal all". I then created a very simple mask shape to hide the top of the sleeve stroke so that it "matched" and lined up with the jacket shoulder area. I tweaked some smart bone actions for the bicep so everything looks correct during rotation.

Each arm group layer can now have animated layer ordering as needed and will line up with the shoulder of the body.

The best part of this whole thing is that the sleeves can be rolled up and down regardless of the bending of the arm. The cuff of the sleeve just follows along the curve of the arm. It all just works silently behind the scenes.
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funksmaname
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Re: Stroke shape arms with sleeves!

Post by funksmaname »

Very nice!
and, afaik, the original stroke technique was created by user 'Onionskining' - http://www.youtube.com/channel/UCFlpAo3fVi9OcF0Ekg700CQ
Danimal
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Re: Stroke shape arms with sleeves!

Post by Danimal »

It looks great and I especially like that you did the head turn using switch layers. I've become too spoiled by video tutorials coupled with my admittedly bad understanding of the software so much of your description was Greek to me. I'm certain it worked though because the animation looks great!
~Danimal
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synthsin75
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Re: Stroke shape arms with sleeves!

Post by synthsin75 »

I believe realsnake (zinger on the AF) started using strokes in lieu of filled shapes first, but I think Onionskin ran with the idea. http://www.kelleytown.com/forum/animato ... OPIC_ID=58 Haven't heard from him in forever.
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Onionskin
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Re: Stroke shape arms with sleeves!

Post by Onionskin »

Hi guys!
I guess the Zinger was the first one, but I never saw his tutorial because it was removed. One of my first post about strokes is here viewtopic.php?f=9&t=15816&p=87405#p87405
After discovering "outlined strokes" I always use strokes for arms, legs, fingers, lips.
Regards!
madriver
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Re: Stroke shape arms with sleeves!

Post by madriver »

Nice! Thanks for posting this!
Lychee
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Re: Stroke shape arms with sleeves!

Post by Lychee »

Hi

Clever construction Vern, i like the idea to create arms, legs and others things with only strokes. Is it possible to share your file for study ?
Onionskin and of course Zinger inspired me Some experimentations with that technic, and here's one of them.



File : https://www.dropbox.com/s/1sy6y9yjh1rmd ... 0Test.anme

The problem with this technic is if you want to do some outlines around an arm or leg, you can only make some straight line without relief (muscles).
But I have a tip for improving the technic and for work around the problem, i would show you it tomorrow in a video
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heyvern
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Re: Stroke shape arms with sleeves!

Post by heyvern »

Yes I can share a sample. I will post a simple file I used to develop this. It's really very very simplistic and easy to set up. Yes there are some limitations, but my goal was to create a very simple character. keep it as simple as possible.

When I did the legs I took it a step further. The hips and legs are all strokes. Basically from the stomach down to the feet is a tapered stroke shape. This is all one continuous stroke to keep the shape smooth. I then put in a cross stroke shape at the crotch area to connect the legs. By adjusting the stroke width I was able to taper the legs just the way I drew the character sketch. I made extensive use of smart bones for the leg rotations to adjust curvature and point width. It works great.

I like working simple. It's hard for me to avoid going to detailed. This character was simple enough I was able to easily do a complete side to front body and head turn with smart bones. Because of the simplistic shapes and low point count the turn was a piece of cake and works quite well. The really trouble area was layer order of the arms and body, getting the shoulder masking correct.
rocky53204
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Re: Stroke shape arms with sleeves!

Post by rocky53204 »

Look forward to an example file.
Paukwa
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Re: Stroke shape arms with sleeves!

Post by Paukwa »

Greetings all.
This is wonderful technique, I have tried to download the sample file but I end up getting a text file, can anyone tell me why is that? I use Mac but I doubt that is the reason. Thank you I hope someone will shade some light on that.
rocky53204
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Re: Stroke shape arms with sleeves!

Post by rocky53204 »

It is probably the lua code with a .txt extension. Try to rename it with a .lua extension.
Paukwa
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Re: Stroke shape arms with sleeves!

Post by Paukwa »

rocky53204 wrote:It is probably the lua code with a .txt extension. Try to rename it with a .lua extension.
sure thanks Roky. I managed o get file from other post now.
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braj
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Re: Stroke shape arms with sleeves!

Post by braj »

About the lines being simple, I add muscles or whatever on another layer like the cuff Vern used, and that gets you more complex shapes while giving easy to set up joints. And of course varying the line width. Like anything it depends on character design, but especially if you want to make a simple rig then 'clothe' it in extra layers later, I think it's perfect.
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