Vector points going nuts in smart bones

[Nishen]

Hi! I'm working on a project that needs a model with complex movements. (180 degree) I came across this video by MultRush with his mix smartbones technique: https://youtu.be/M0RJEjA21f8?t=34 (Russian video with English subtitle)

Problem is, whenever I try to do as he says by moving the two bones I wanna mix, (around 1:02 mark) the point in the vector layer goes completely out of control. I can't control the bezier handles, and any small movement causes the vector point to jerk into crazy positions, even if I try to move just one point. I have several smartbone actions that need to be mixed for this project, and if I can't find a solution, everything will fall apart. Here is a demo project and two videos demonstrating the issue, and a small preview of the actual character model: https://drive.google.com/drive/folders/ ... sp=sharing

Any help is greatly appreciated! I've spent months planning the model and learning the software. I could scale it back down to the point of animating simply with switch layers like traditional cutout animations, but if I can get this one issue fixed, I could animate the model in a way that creates illusion of it being 3D. Many Thanks in advance!

[Greenlaw]

I haven't looked at your files yet but as soon as you mentioned Bezier handles, I suspected that. In my experience, Bezier points can be unreliable when using bones deformations or complex Smart Bone Actions, I find it's best to stick regular points instead of Bezier points. Regular points deform more predictably and are far easier to control in these situations.

Generally speaking, I only use Bezier points for non-deforming artwork (like props and backgrounds,) or in situations where I know the deformations will be simple and straightforward. (For example, probably without using multiple Smart Bones or meshes.)

Tip #1: I prefer to work with Show Bezier Handles disabled until I need them; this way way I won't accidently activate Bezier mode. If I accidentally switch to Bezier mode, I can reset the points by resetting the curvature of the point. Then I'll make sure the disable the visibility.

Tip #2: The Curvature tool doesn't have the Show Beizier Handles option, but it can be added using Wes' Curvature tool mod found here...

bezier curve option

This is highly recommended and I'm my opinion this mod should be in Moho by default.

If for some reason, you absolutely must use Bezier points in a deforming shape, Victor posted suggestions here:

Bezier points not working as expected

Personally, I'd still avoid Bezier when I'm making complex rig setups. I may have to add a few extra points to get the same curves but It's so much easier to deal with when something isn't animating as expected.

BTW, what I'm describing above isn't a bug in Moho, it's just the nature of working with Bezier points in these situations.

Hope this info is helpful. I''ll try to look at your files later today if I have the time, and hopefully another user here can get to it sooner and share some good answers with you.

[Nishen]

Thank you very much greenlaw, I really appreciate the quick respose! What you say does make a ton of sense, in hindsight. But I guess part of the learning process is trial and error. So according to your suggestion it's best if I go back and redo everything to have as little bezier handles as possible. That's a tremendous amount of work, since I have dozens upon dozen of layers that needed to deform, but it sure is better than abandoning my entire project. Thank you again, I'll check if it resolves the issue. Let me know if you get a chance to take a look at the files.

[Greenlaw]

...I guess part of the learning process is trial and error. So according to your suggestion it's best if I go back and redo everything to have as little bezier handles as possible. That's a tremendous amount of work, since I have dozens upon dozen of layers that needed to deform, but it sure is better than abandoning my entire project.

I think the official documentation could probably do better with explaining the pros and cons of using Bezier points in Moho...it seems like a lot of new users run into this problem. I recall Mike releasing a video years ago when Bezier points were introduced in Moho (which was Anime Studio at the time) that demonstrated situations in which Bezier curves could misbehave. I'm not sure where that video is now but maybe we need a new video on the topic.

That said, it may not be necessary to re-do your entire rig. If most of the rig is working fine for your, I would fix only the parts that are misbehaving, and keep this info in mind for your next rig.

[hayasidist]

whilst Bezier is, as Greenlaw says, likely to give you a headache, I think the bigger problem stems from conflicts between the 2 smartbones fighting each other for control of the same points.

https://www.lostmarble.com/forum/viewtopic.php?t=31183 has an approach to solving this.

[Greenlaw]

I just watched an old video on this topic by Danny Sugar and he has an interesting way to work with Bezier points in Moho...

Bezier, Simplify, Boolean & Freehand improvements

In the video, Danny likes to leave the handles hidden the way I do, but instead of using the Curvature mod I suggested, he presses-and-holds the C key to temporarily reveal the handles. Then, when he also presses Alt, he can break the tangent and adjust it. (Pressing-and-holding C actually temporarily switches to the Curvature tool.) Then, when he releases the C key, Moho returns the Transform tool.

I just tried this technique and it has some interesting advantages. I'll probably stick with my usual methods but I can see how this might work better for some users.

Note: you cannot use this method if you have the Curvature mod installed. If you have the mod, the handles will not appear when you press the C key like it does in Danny's video.

[Nishen]

whilst Bezier is, as Greenlaw says, likely to give you a headache, I think the bigger problem stems from conflicts between the 2 smartbones fighting each other for control of the same points.

https://www.lostmarble.com/forum/viewtopic.php?t=31183 has an approach to solving this.

Hmm, I didn't follow that video all that much in favor of the mix smartbone script, but I'll take another look now. Thanks!

[Greenlaw]

Good call Paul!

@Nishen: The Mix Smart Bone script you tried is handy but you should understand why the conflict occurs in the first place, and then learn how to fix this issue manually. The video from MultRush in the thread cited by Hayasidist explains how to create your own mix Smart Bone Dial without the script...highly recommended!

The Mix Smart Bone script is a great shortcut for common Smart Bone conflict situations but if you don't understand how it attempts to solve the problem, it could make things worse.

Since you're still learning Moho, I suggest fixing the Smart Bone conflict problem manually first, and then try the script with a duplicate copy of the project so you can compare the results. From there you may come to understand the limitations of the script and also know how to work around those limitations.

[Nishen]

I just watched an old video on this topic by Danny Sugar and he has an interesting way to work with Bezier points in Moho...

Bezier, Simplify, Boolean & Freehand improvements

In the video, Danny likes to leave the handles hidden the way I do, but instead of using the Curvature mod I suggested, he presses-and-holds the C key to temporarily reveal the handles. Then, when he also presses Alt, he can break the tangent and adjust it. (Pressing-and-holding C actually temporarily switches to the Curvature tool.) Then, when he releases the C key, Moho returns the Transform tool.

I just tried this technique and it has some interesting advantages. I'll probably stick with my usual methods but I can see how this might work better for some users.

Note: you cannot use this method if you have the Curvature mod installed. If you have the mod, the handles will not appear when you press the C key like it does in Danny's video.

Glad to see all these options I can try. Makes me feel hopeful that I can find a working solution sooner rather than later. I'll test this method, and if doesn't solve my issue, I'll try the curvature mod.

[Nishen]

Good call Paul!

@Nishen: The Mix Smart Bone script you tried is handy but you should understand why the conflict occurs in the first place, and then learn how to fix this issue manually . The video from MultRush in the thread cited by Hayasidist explains how to create your own mix Smart Bone Dial without the script...highly recommended!

The Mix Smart Bone script is a great shortcut for common Smart Bone conflict situations but if you don't understand how it attempts to solve the problem, it could make things worse.

Since you're still learning Moho, I suggest fixing the problem manually first, and then try the script with a duplicate copy of the project so you can compare the results. From there you may come to understand the limitations of the script and also know how to work around those limitations.

I agree completely. That script is awesome but if I have no idea what goes under the hood, I'll be in trouble as soon as something goes wrong. I'll dedicate more time to study that video as you recommended. I'm very grateful for all this support and advice from everyone. It's invaluable!

[Daxel]

I use that mix_smartbones script sometimes, and always worked correctly. I think we are mixing some things here:

1. Bezier handles (or bezier points, that are points that have their beziers active because they have been manipulated by the user) are harder to animate because they are just more complex. You have nice tips on how to tame them for animation.

2. Bezier handles have bugs (or at least one bug) that is the one I explain in the post that GreenLaw linked to share Victor's advices about animating bezier points. That specific bug is not the cause of your problem as it seems to happen only with rotating and shortening bones binded to artwork that contains bezier points. But it's a reported bug and I hope we can get a fix sooner than later.

3. As you guessed the problem is probably that you didn't use the Mix_Smartbones script as intended. Try following the video instructions step by step and tell us how it goes.