There is already some work-in-progress for this feature (I think it will appear on v1.2 beta2).
https://twitter.com/davidcapello/status/741271831840194560

Implemented, this will be included in the next v1.2-beta2

@dacap super! Will you also include a subfolder as a parameter for aseprite cli for --filename-format?

@nakedpony I'm still thinking about this (as well as the Export Sprite Sheet when "Selected layers" are chosen). I think this is highly related to #1174

Maybe something like {layer} (the same as {layer0} for the first level), {layer1}, {layer2} etc. What do you think?

I guess it makes sense to be able to filter out layers/folders by by index as well as by name if I understand correctly your approach in #1174 and with folders.

I was thinking and they are two different things. #1174 talks about a way to filter layers by name (I still need a syntax children, e.g. --layer "parent > child" to pick just one children).

The other one is about --filename-format or --save-as: For example --save-as {layer}-{layer1}-{frame}.png to save each frame of each layer with filenames like TopLevelLayerName-FirstChild-0.png, TopLevelLayerName-SecondChild-0.png, etc.

Anyway I'm not yet sure about this {layer1} syntax. Maybe {layer} should be always the layer name (in case we want to save all layers/groups/children with its layer name --save-as {layer}.png should work). And we could add new terms like {group} to indicate the name of the first parent group, {surgroup} for the parent of the parent, etc.

Oh, I see now. You want to introduce multiple nesting of the layers. So I think that selecting layers could be as you described. And I guess --layer "parent > child" would imply --layer "parent > child > *".
Though at the moment it's possible to just hide non wanted layers in UI so they won't be neither listed via --list-layers nor imported (means some manual work).

As for format when importing deep nested structure of layers... Let's look at the variants:

• {layer1}-{layer2}-{layer3}-{layer4}-{frame}.png - would work for any amounts of levels but not backward compatible. Because some people would still use {layer}
• {layer}-{sublevel1}-{sublevel2}-{sublevel3}-{frame}.png - this one is backward compatible and would scale
• {layer}-{group}-{subgroup}-{subsubgroup?}-{frame}.png - doesn't really scale

@dacap BTW it would be a huge improvement if every layer could be exported separately to multiple tags aka animations to unity format. Similar to this script https://github.com/talecrafter/AnimationImporter but splittable by layer. Just a task I'm struggling with at a moment. I guess it could make aseprite even more popular and easy to use :)

@nakedpony about the improvement "if every layer could be exported separately to multiple tags," I'm not sure if I understood this correctly, but actually on v1.2-beta1 you can use something like:

aseprite -b myfile.ase --save-as '{layer}-{tag}-{frame}.png'

Or maybe you want all frames of each "layer+tag" combination in one .png? In that case I'm thinking that we might have something like:

aseprite -b myfile.ase --sheet '{layer}-{tag}.png' --data '{layer}-{tag}.json'

(Not yet implemented.)

About the group identifiers, I've found an alternative:

• {layer} identifies the current layer (it can be a group or layer)
• {group} identifies the first parent/group
• {parent1}={parent}={group}
• {parent2} the parent of the parent, etc.
• {topgroup} the first group in the hierarchy of the current layer
• {topgroup1}={topgroup}
• {topgroup2} the child of the first group, etc.

I'll just add {group} for the first iteration (v1.2-beta2).

I'm implementing this and more tricky scenarios are appearing. For example, if we have this structure:

We might try to use:

aseprite -b player.ase --save-as player-{group}-{layer}.gif

In this case, I'm sure that this should generate at least 4 files:

player-head-eyes.gif
player-head-shape.gif
player-body-arms.gif
player-body-shape.gif

But I'm not quite sure about the other layers (the groups). Should it generate the following files?

player--head.gif
player--body.gif

Or these other files?

player-head-head.gif
player-body-body.gif

I think that in this case it should generate 4 files and nothing else. And if we use the following command:

aseprite -b player.ase --save-as player-{group}.gif

It generates the following files:

player-head.gif
player-body.gif

There are a lot of tricky combinations and I'm not so sure what to do on each case. I'll thinking more about this and try to find a "good enough implementation" for the first version.

going to take a look at this thread later tomorrow :)

it's more than enough for me for the first version :)

There is a part of this issue that wasn't yet implemented and I'll try to implement for v1.2-beta3, #1238