Linked Paths vs. Path Constraints Skins?

skarasuko

I was wondering if the alternative of Linked Paths was considered before. The reason this has been in my mind is because the alternative method could have decreased the Slot Count total and removed the need to create another Transform Constraint. For example, having multiple Skins of different Paths for a vehicle's treadmill. This would be useful if the mix data is not required to change with each Skin.

Misaki

I'm afraid I don't understand what you mean by that. Do you want path attachments to be able to be put in skin placeholders? I'm not sure why you mentioned transform constrainets in the middle of your description, are you referring to path constrainets?

skarasuko

Oops. Yeah, I meant Path Constraints. I am already aware Paths can be placed in Skin Placheholders, but anytime a character or object needs a different Path in a different Skin, I need another Path Constraint for the set of bones to refer to. In total, this means another Slot and Constraint in the whole project.

What I was thinking about was essentially giving the Path Attachments the same feature as Linked Mesh, so the Deform Keys are applied to the "Linked" Path in the Animation. It could lessen the number of Slots and Constraints.

Misaki

Thank you for clarifying your question! However, I guess there may be some misunderstanding regarding the following point:

but anytime a character or object needs a different Path in a different Skin, I need another Path Constraint for the set of bones to refer to.

Path constraints can change the Target for each skin, so a setup like the one seen in the GIF animation below is possible.

In the example above, SkinA and SkinB contain the same path constraint, but the target paths are circular Path-A and distorted Path-B, respectively.

If you don't want to share the path-constraint's settings (Spacing, Position, Rotate mode, Mix, etc...), you will have to create a new path-constraint for each skin, but if the same settings are fine, there should be no need to create a new one.

If this doesn't seem to solve your problem, please let me know!

skarasuko

Without some kind of "Linked" Path, this can be a problem when you have multiple skins that need the same Path and its Deform keys. Say you have 5 Skins, but 3 of them needs the same path. 2 of them needs the other path. Any Deform keys you make in the Animation does not apply simultaneously to the Duplicate Path inside the Slot, because it does not follow the Original Path.

Right now, the alternative is to set the different Path shape in its own Slot and utilize Constraints Skin. Like I said, this currently needs an extra set of Slot and Constraint.

Misaki

I see, so the biggest reason that you want to linked paths is to share the deform keys. However, the current best solution for that is to not deform the path attachments directly, but to bind them to bones, set weights, and key the animation of the bones to deform path attachments. The bind bones and weights settings for that path attachment will be inherited when it is duplicated, so it would be useful. Do you have any reasons why you need to deform the paths directly?

I hope you understand that I am not disagreeing with you on this suggestion, I would just like to confirm the details because we must clarify what it will be needed for and in what case whenever we are going to create an issue ticket for any additional features or improvements.

skarasuko

Misaki yazdı
I see, so the biggest reason that you want to linked paths is to share the deform keys. However, the current best solution for that is to not deform the path attachments directly, but to bind them to bones, set weights, and key the animation of the bones to deform path attachments. The bind bones and weights settings for that path attachment will be inherited when it is duplicated, so it would be useful. Do you have any reasons why you need to deform the paths directly?

I hope you understand that I am not disagreeing with you on this suggestion, I would just like to confirm the details because we must clarify what it will be needed for and in what case whenever we are going to create an issue ticket for any additional features or improvements.

I understand the statement. I already bind the paths to bones, but the bind setup can vary wildly depending on certain subjects. The point is, Spine Projects can change a lot if necessary. This theoretical feature I mentioned with Linked Paths could mitigate certain problems while making changes in projects.

For example,it is possible that I find the Path's Weights unsatisfactory and decide to adjust it. But this does not immediately transfer to the Duplicated Path I have created. Basically, it is easy to develop inconsistencies in the whole project after creating Duplicate Paths. And it is especially difficult to decide quickly on the Bind setup for very fluid characters / objects, like a Blob Enemy. I currently prefer to manually Deform the Paths to make realistic movements and interactions for these type of subjects.

An interesting example would be a set of characters with a Blob Heads. Their shape would vary and needs their own path, but the path is bound to 3 sets of bones that act as a Neck and Head. These paths' Deform Keys are used to give their heads some fluid movement and wobble in the animations. However, some Heads can have different textures and additional objects on them that needs new Skins, but the same Path. Ultimately, I need a new Path Slot and Constraint "per shape" to be able to adjust the Weights of the Paths and animate them without concerns of inconsistency with the Skins.

Misaki

Thank you so much for elaborating on it. Adding linked path attachments seems reasonable, so I created an issue ticket for this:
https://github.com/EsotericSoftware/spine-editor/issues/667

You can subscribe to the issue ticket, then you will receive additional notifications upon any progress. If you have anything you would like to add, please feel free to add your comments directly to the issue.

skarasuko

Thank you. I am hoping for the best.