Masking eyes and using bones

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Hoptoad
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Masking eyes and using bones

Post by Hoptoad »

Image

I'm making a character with huge eyes and my usual method of making eye rigs aren't providing the results I need.

In the image above, the left iris (the colorful part of the eye) should be masked by the sclera (the white part of the eye).

Also, I need the sclera to be masked by the head.

And I need each iris to be controlled by a bone so that I can animate the eyes easily from the bone layer.

None of my rigs are working. If they solve one problem, they create another. For example, if I mask the irises properly, I can't create bones to move the irises.

This type of rig is possible, isn't it? If so, what should my rig look like?

This is my most recent layer structure, which produced the image displayed above:

> BONE LAYER: Character
> > GROUP/MASK LAYER: "eyes"
> > > "iris" (mask this layer)
> > > "sclera" (mask this layer)
> > > "head" (add to mask, exclude strokes)
> > GROUP LAYER: "body"

Thanks for your help. I've examined bone rigs in the Library and watched tutorials, but didn't find a solution.
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Greenlaw
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Re: Masking eyes and using bones

Post by Greenlaw »

I like to make each eye in its own group so they each have simpler masking. For me, keeping things simple usually works best.

So in this case, group the head with mask that effects both eye groups, then each eye group will have a mask to mask the iris. Here's an example...

Image

Download: eyes.moho

The catch is that the preview in the workspace can look odd. This is a current shortcoming of Moho's display capabilities but it doesn't affect final render quality as seen in the render preview window on the left.

There are some workaround techniques for making the display look correct but they can be convoluted, so I'm just explaining the simplest approach here.

BTW, if you look at the rig demo section from my old Puss-In-Boots reel from 2018, you can see the issue existed back then too. In the demonstration, you can see Puss' eyes stray outside of his head when he turns. This anomaly did not affect the final render quality at all, so I just ignored it during animation.

That said, I'm still hopeful that Moho's developers can improve this in a future release of Moho.

Hope this helps.

Additional note: I did something in the setup worth pointing out. For the head group, instead of relying on Exclude Strokes, I used a duplicate head layer on top with the Fill knocked out. This is mainly to improve the preview quality. I could have done the same for the eyes but left those alone in this example.
Last edited by Greenlaw on Thu Mar 09, 2023 6:28 am, edited 3 times in total.
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Greenlaw
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Re: Masking eyes and using bones

Post by Greenlaw »

Oh, there's another approach you can try that uses only limited masking, and mostly relies on creating holes in a layer instead. This method requires an extra step but its easy to do and tends to look more correct in the preview display.

Unfortunately, I can't find the thread because the forum's search feature hasn't been working properly lately. If I have time today, I'll check if I have the link in my personal notes and share it here.

If I can't find it, I'll make another example when I have time.
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Hoptoad
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Re: Masking eyes and using bones

Post by Hoptoad »

Greenlaw wrote: Wed Mar 08, 2023 9:27 pm Oh, there's another approach you can try that uses only limited masking, and mostly relies on creating holes in a layer instead. This method requires an extra step but its easy to do and tends to look more correct in the preview display.

Unfortunately, I can't find the thread because the forum's search feature hasn't been working properly lately. If I have time today, I'll check if I have the link in my personal notes and share it here.

If I can't find it, I'll make another example when I have time.
Ha ha, that's one of my favorite methods - making a face with two holes for eyes, and the eyes and eyelids are behind the face.

I was just hoping that there was a way to attach a bone to an iris, when the iris is in a mask. It's looking like there's no way. If there's no way to do such a thing, that's fine. I just wanted to be sure before I moved on to Plan B.
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Greenlaw
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Re: Masking eyes and using bones

Post by Greenlaw »

Hoptoad wrote: Wed Mar 08, 2023 9:36 pm I was just hoping that there was a way to attach a bone to an iris, when the iris is in a mask. It's looking like there's no way. If there's no way to do such a thing, that's fine. I just wanted to be sure before I moved on to Plan B.
That should be doable...I use bones to move masked iris drawings all the time. Can you show an example of how that doesn't work?
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Greenlaw
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Re: Masking eyes and using bones

Post by Greenlaw »

I was trying to think of situations where the bones wouldn't work, and can really only think of one:

Are you using Bind Layer for the Eyes group? If so, unbind that and instead use Bind Layer for each iris or Bind Points for each iris.

When Bind Layer is used for a group, Moho prevents the contents of that group from being bound to other bones. In other words, its as if everything inside that group is bound to the same bone. If you don't use Bind Layer on the group the contents are free to use different binding.
Last edited by Greenlaw on Thu Mar 09, 2023 6:26 am, edited 1 time in total.
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Hoptoad
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Re: Masking eyes and using bones

Post by Hoptoad »

I didn't see your helpful illustrations and the downloadable Moho example when I first replied. Sorry. Thank you for your help! The illustration and example provided me with the solution I needed.
Greenlaw wrote: Wed Mar 08, 2023 9:20 pm The catch is that the preview in the workspace can look odd. This is a current shortcoming of Moho's display capabilities but it doesn't affect final render quality as seen render preview window on the left.
It didn't occur to me to generate a Preview to see if masking had worked. :shock:

I appreciate the Pro Tip regarding the duplicate layer with the fill knocked out. I had noticed the almost unnoticeable defects in my renders, so this tip was extremely welcome.

You guessed correctly, by the way. I had bound the group layer, which prevented bones from connecting to the nested irises. I had a feeling it was user-error, but couldn't locate the problem. I forgot to check for that seemingly trivial but nonetheless devastating "don't do this" violation.

Thanks again! I'm using your Moho example to improve my character rig. It will be so much better now.
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Greenlaw
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Re: Masking eyes and using bones

Post by Greenlaw »

Glad that helped!

Here's one more tip: disabling GPU Acceleration in the Display Options list should improve how nested masking looks. It can still have flaws (like in the above example) but it should look better. There are situations where I want GPU Acceleration enabled, but I leave it off most of the time because some features I rely on look better when it's off.
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