Tips for using meshes with vector layers

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Daxel
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Tips for using meshes with vector layers

Post by Daxel » Sun Nov 10, 2019 1:05 am

Hi!

I've been doing lots of tests with meshes over vector drawings to understand how they work but I failed miserably.

I'm taking notes on the things I'm understanding but there are still some things that I just can't:

1. I create a vector drawing. I create a mesh. I go to the vector drawing layer settings, choose it to be controled by the mesh. Click apply and those settings get reset (the mesh is no longer selected to be controling the layer) And of course the mesh doesn't affect the layer. I dont know what I'm doing wrong.

2. I do exactly the same but this time, I don't know why, the mesh remains configured after clicking apply. I go to frame 1 to test the mesh: the drawing colapses into oblivion. At first I thought that making the mesh bigger solved the problem. Other times it seems like making the mesh bigger doesn't work anymore.

Do the meshes need to have certain characteristics? I don't know what am I doing wrong, right now is like random. Please I need some tips.
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synthsin75
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Re: Tips for using meshes with vector layers

Post by synthsin75 » Sun Nov 10, 2019 3:04 am

Can you share an example file of the problem?

I seem to recall some issues with assigning meshes, but that was fixed. Are you using the latest update for the version of Moho you're on?
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Greenlaw
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Re: Tips for using meshes with vector layers

Post by Greenlaw » Sun Nov 10, 2019 6:04 am

Which version of Moho are you using? FWIW, I'm using the latest 13 and mesh warping seems to work fine here.

Yes, posting an example project will help us see what he problem is.

Without seeing anything, my guess is that the vector drawing wasn't created to support the deformations your attempting with the mesh (i.e., not enough segmentation or inappropriate use of bezier curves.)
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Daxel
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Re: Tips for using meshes with vector layers

Post by Daxel » Mon Nov 11, 2019 3:01 pm

Greenlaw wrote:
Sun Nov 10, 2019 6:04 am
Which version of Moho are you using? FWIW, I'm using the latest 13 and mesh warping seems to work fine here.

Yes, posting an example project will help us see what he problem is.

Without seeing anything, my guess is that the vector drawing wasn't created to support the deformations your attempting with the mesh (i.e., not enough segmentation or inappropriate use of bezier curves.)
Thank you both for your answers! Sorry that I couldn't answer yesterday.

First of all: I'm using Moho 12.5 on Windows 10.

I made a youtube video showing one of the problems I have: that the mesh seems to need to be very big to work properly (otherwise the vector layer kind of implodes?) and I don't know why or if I'm doing something wrong.

Youtube video: https://youtu.be/v10H8CeqPuo

Minimal reproduction proyect file: https://drive.google.com/file/d/1830QE6 ... sp=sharing

The second problem was that when I click "apply" to link the vector layer to the mesh on the vector layer settings window, the selected mesh gets unselected and then I cannot select it (it's not an option anymore) but today I wasn't able to reproduce that problem so I'm focusing on the other problem.
Last edited by Daxel on Mon Nov 11, 2019 3:56 pm, edited 1 time in total.
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Re: Tips for using meshes with vector layers

Post by Daxel » Mon Nov 11, 2019 3:55 pm

Aditional findings:

*Problem definition: the mesh seems to destroy the drawing it controles (you have to go to frame 1 or more too see it), it looks like the drawing implodes to the center of the layer. I have to make the mesh so much bigger than it should be just to prevent that from happening.

[*]Test 1: Another Vector Layer and Another Drawing: no problem
I tried to delete the eye vector layer and make a new one with a new drawn eye: the problem stops happening (a mesh just big enough to cover all the drawing points works well as it should).

[*]Test 2: Same Vector Layer but another drawing: yes problem
This time used the same original vector layer, but with the Transform Point Tool I clicked on Edit - Select all, and deleted to make sure that the drawing was fully deleted. I redraw a new eye and the problem happened. I even tried drawing just a simple circle but the problem keeps happening.

[*]Test 3: Another Vector layer but same drawing (copy pasted) yes problem:
Ok just when I felt I was going somewhere, thinking the problem was on the vector layer, this happens. I'm pretty lost.
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Greenlaw
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Re: Tips for using meshes with vector layers

Post by Greenlaw » Mon Nov 11, 2019 4:14 pm

Wow, that is pretty weird. I'm not sure why this particular setup didn't work. I tried your project in Moho 12.5. FWIW, mesh warping should work fine in Moho 12.5--I've used it regularly. Maybe the scale of the art is too small for the number of points you've drawn in both the mesh and the eye? Just a guess.

I don't normally use a grid mesh unless the artwork calls for it. If you're going to use a custom mesh, I think it's better to create a mesh that conforms to the shape of your artwork. To check this, I edited your eye art to have fewer points and created a custom mesh that conforms to the eye shape more closely, and this is the result. TBH, this example works just okay. I think this could be made better but I didn't want to spend too much time on it.

Image

For this sort of thing, I would just animate the eye points directly as in the second row. Unless you're planning to do something unusual with the eye deformation, I don't see any benefit in using a custom mesh here.

I know that doesn't really answer your question but I hope it gives you some ideas to explore.
Last edited by Greenlaw on Mon Nov 11, 2019 7:56 pm, edited 2 times in total.
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Re: Tips for using meshes with vector layers

Post by Greenlaw » Mon Nov 11, 2019 5:05 pm

Here's an example of how I like to use a custom mesh warp for the eye...

In this example, the mesh is used to reshape the whole eye to change perspective:

Image

But to close the eye, I animate the points directly. In this case, using a smart bone action to move the points. (Up is for a 'smiley' close, and down is for a 'sleepy' close.)

Image

You can see the mesh itself has very little affect on this animation. Here, the mesh is mainly used for corrective shaping and not for the main animation.

I'm not saying that this should always be the case, just presenting how a mesh is used in this particular example. In my experience, each unique character may require its own rigging approach. You'll have to use your best judgment for the most effective way to animate your character.

I hope this helps and gives you some ideas to try. Good luck!
Last edited by Greenlaw on Mon Nov 11, 2019 7:59 pm, edited 3 times in total.
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Daxel
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Re: Tips for using meshes with vector layers

Post by Daxel » Mon Nov 11, 2019 5:38 pm

Greenlaw wrote:
Mon Nov 11, 2019 5:05 pm
Here's an example of how I like to use a custom mesh warp for the eye...

I hope this helps and gives you some ideas to try. Good luck!
Thank you so much! I always learn a lot from your explanations on this forum.
That was exactly the technique I was trying to explore, to use meshes for head turns like that. But when I face something that I don't understand like this mesh behaviour I always try to understand it before keep going so I don't make the same mistake in the future. But this mistery is being hard to solve for me!

I will keep trying to understand it and doing tests, and will update if I find something out.
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Re: Tips for using meshes with vector layers

Post by Greenlaw » Mon Nov 11, 2019 6:16 pm

Sure, glad to help. I'm sorry I can't explain the original problem...I want to take another look at it later and try to understand it better myself.

Here are some more tips:

Tip 1: If it helps, think of each point in the Smart Mesh as a kind of Point Bone. Each mesh point moves anything within its range, and each mesh point has a falloff...that is, the point's strength falls off across distance, just like in a Point Bone. Also keep in mind that the mesh points all have the same level of strength, and the way to control the influence of each point is to put more or less space between them.

When you're using a custom mesh to animate a vector layer, a mesh point directly on top of a point in the vector layer is going to have the strongest influence over all the other points in the mesh. This is why a grid shaped mesh isn't necessarily the best design for a vector layer.

Keep all of the above in mind when designing your Smart Mesh.

Tip 2: A grid mesh can be ideal for warping an image layer as a whole object, like a flag, a banner, or maybe a blanket.
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synthsin75
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Re: Tips for using meshes with vector layers

Post by synthsin75 » Tue Nov 12, 2019 12:00 am

The problem is what I found here: https://www.lostmarble.com/forum/viewto ... 74#p186574

Your file can be solved by scaling the smart mesh points up until the eye quits jumping on frame one, and then scale the smart mesh layer back down to the original size. The issue has already been reported to the devs.


I use grid meshes all the time, for all kinds of stuff. They never cause me any trouble.
Daxel
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Re: Tips for using meshes with vector layers

Post by Daxel » Tue Nov 12, 2019 12:23 am

Greenlaw wrote:
Mon Nov 11, 2019 6:16 pm
Sure, glad to help. I'm sorry I can't explain the original problem...I want to take another look at it later and try to understand it better myself.
I made it!
I dont understand why this problem happens, but after many tests now I know what is happening and how to solve it without having to make changes to the drawing or to the mesh!

Cause of the problem:
The size or complexity of the drawing doesn't matter. The problem happens when any of the triangles of the mesh is too small. Relative to what? to its own layer (the mesh layer). More on this later.


Solution to the problem
The problem was solved when I made the mesh bigger using Transform Points tool because that made all its triangles bigger relative to its layer. But that was not a good solution because then I had to make the drawing also bigger to match the mesh. But now that I understand that the problem is the size of the triangles relative to its layer, the solution is just to make the mesh layer smaller with Transform Layer tool, and make the mesh normal size again with the Transform Points tool. So this way the rest of the character and drawings doesn't have to be touched at all.

Solution on video: https://youtu.be/9C6qdJQ6IqU

Why do we have this limitation on the size of the triangles of a mesh relative to its layer? Is it a bug? It is affected by something else (maybe proyect settings)? I don't know. Now that I have an easy non destructive solution I will be fine but this could drive someone crazy so I guess that devs should be aware of it so they can solve it or just put it on the documentation if somehow is not a bug.
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Re: Tips for using meshes with vector layers

Post by Greenlaw » Tue Nov 12, 2019 12:30 am

Good detective work guys!

Thank you for sharing that video, Daxel.
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Re: Tips for using meshes with vector layers

Post by Daxel » Tue Nov 12, 2019 12:33 am

synthsin75 wrote:
Tue Nov 12, 2019 12:00 am
The problem is what I found here: https://www.lostmarble.com/forum/viewto ... 74#p186574

Your file can be solved by scaling the smart mesh points up until the eye quits jumping on frame one, and then scale the smart mesh layer back down to the original size. The issue has already been reported to the devs.


I use grid meshes all the time, for all kinds of stuff. They never cause me any trouble.
Damn, I've been 30 minutes reporting my findings in my previous answer and didn't see your answer. It's exactly what you said, thanks for answering, Wes. I tried looking for the problem on the forum but didn't have luck. I'll try harder next time.
At least maybe my full explanation could be usefull for some other people searching for this.
Thanks everyone!
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