Reference layers and coordinate frame of reference

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dondo
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Reference layers and coordinate frame of reference

Post by dondo »

So I have two characters passing a basketball to one another. The ball has to exist between the hands of each character, and has to fly between them (and others). So based on earlier teachings from the Moho Jedis on this forum, I know that I'll need to create a basketball, then a couple reference layers to it, and then move the ball (and switch on and off visibility appropriately between the reference layers). This has worked great in other contexts, but when I move the reference layer into the character rig, the ball immediately becomes tiny, spins, and distorts - and then moving it around goes whacky. I'm assuming this is because the reference is now subject to the coordinate system of the bones, but it's really time consuming to address by hand. I've tried [bone / Release Layer and Points]; that fixes the distortion, but the ball remains shrunken and turned.

Is there a straightforward way to have a prop move between characters? (I couldn't find a good reference - please refer me to a tutorial or documentation if this represents a failure of my web search skills.)
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synthsin75
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Re: Reference layers and coordinate frame of reference

Post by synthsin75 »

First, it's best practice to avoid layer transforms when creating assets. If at all possible, save layer transforms for animation, especially for groups. Second, create assets to the same scale. Following both of these will keep groups the same scale, so putting a layer into them won't change it.

Fixing stuff after you already have groups at different scales can be difficult. Not sure there's an easy fix for that.
dondo
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Re: Reference layers and coordinate frame of reference

Post by dondo »

That solves the part of the problem I'd already kinda figured out. The real problem is that when I put the reference layer into the bone layer, the coordinate system changes.

So for example I drew a random vector shape, created and dragged the reference layer into the character rig, and the shape in the reference layer moves away from the target. If I fix that so they're on top of each other, I've "M" manipulated the reference layer, so moving the target will no longer move the reference.

I must be missing something obvious.
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synthsin75
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Re: Reference layers and coordinate frame of reference

Post by synthsin75 »

dondo wrote:So for example I drew a random vector shape, created and dragged the reference layer into the character rig, and the shape in the reference layer moves away from the target.
If all the parent group origins don't align with the original, the reference will be offset. As I said, you can't do ANY layer transformations (translate, scale, rotate, skew, x/y rotate, etc.) on any of the parent layers.

It sounds like you might be better off working with duplicates instead of references. That just means that you have to animate/scale each copy separately, when it needs to show. Onionskin should help align them at the swaps.
dondo
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Re: Reference layers and coordinate frame of reference

Post by dondo »

synthsin75 wrote:First, it's best practice to avoid layer transforms when creating assets. If at all possible, save layer transforms for animation, especially for groups. ... You can't do ANY layer transformations (translate, scale, rotate, skew, x/y rotate, etc.) on any of the parent layers.
Ok, sorry for being obtuse. This finally sank in, and - wow, duh. When I scale a group, the scale is propagated down the chain and affects all the assets in the group, so when I move a new asset into it, that scale applies. This is... pretty obvious in hindsight. Fixing the scale is pretty easy math (new asset scale divided by container scale). So that helps a lot.
synthsin75 wrote:If all the parent group origins don't align with the original, the reference will be offset.
I'm not sure what "align with the original" means here - original what?
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synthsin75
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Re: Reference layers and coordinate frame of reference

Post by synthsin75 »

dondo wrote:
synthsin75 wrote:If all the parent group origins don't align with the original, the reference will be offset.
I'm not sure what "align with the original" means here - original what?
Align with the source layer of the reference.
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