Using a compound path as a clipping mask for inner shapes

[Valerio]

Hi, I'm not exactly new to the software but I'm delving into some more complex topics as I keep using it for random stuff.

For a simple illustration project, I'm trying to merge the shapes of a character's body while avoiding using destructive operations. What I'd love to achieve is to use a compound shape (made using Alt + boolean Add operation) as a clipping mask for some inner shapes.

See the attached example for what I'm trying to achieve (with a very simplified character) and the tests I have made so far.

From what I gather I have three options:

1. Use a compound path. This will unfortunately break clipping functionality, and the clipped shapes will get lost inside the original containing shape (Body in teh example). If I move them to the root of the compound the simply become part of the compound itself.
2. Make a compound path, group the inner shapes, then use a copy of the compound path as a compound mask for the grouped inner shapes. This works(ish) but messes with rendering and the inner shape with the gaussian blur FX will exhibit some color banding. Not sure it's noticeable in the example picture, but it definitely is there.
   This option is kind of a chore to maintain as well, as I'd have to make changes to both the compound path and the mask. It also makes a mess in the level hierarchy.
   (Note: the color banding seems to be caused by the pass-through rendering mode of the group. I could bypass this by not using a group, and just duplicate the compound yet again to make a mask for each inner shape, but that makes it even harder to maintain)
3. Simply boolean add the shapes. This is visually what I'd like to achieve, but it's a destructive operation. I would need to keep a non-merged copy in case I need to move or redo the ears, for example. Maintaining both copies synced would be a major pain and simply not a good workflow.

I'd like to just use the first option, since it's simple and non-destructive, to achieve the visual result of the third option, but I can't get it to work that way. Is it not possible for compound paths to act as clipping masks as well? What other options are there that I'm missing?

[Aammppaa]

In version 2: You can use a Symbol to keep your Composite Body and Composite Mask in Sync. Doesn't solve the banding on the gradient though.

[firstdefence]

Compounds don't retain individual colours like illustrator does and until the compound feature does it will always be messy.

You could make an outline to enable clipping of the belly  and anything else that overlaps the outer edge of the shape, so you can use the compound feature to create an outer curve, you do this by duplicating the compound and then converting it to a curve. Unfortunately you would need to do this again if you had to move arms ears etc but it is what it is and until the compound can retain individual colours I don't see a way round this, although there are some creative problem solvers on here that know a better way. 

[Valerio]

3 hours ago, firstdefence said:

Compounds don't retain individual colours like illustrator does and until the compound feature does it will always be messy.

You could make an outline to enable clipping of the belly  and anything else that overlaps the outer edge of the shape, so you can use the compound feature to create an outer curve, you do this by duplicating the compound and then converting it to a curve. Unfortunately you would need to do this again if you had to move arms ears etc but it is what it is and until the compound can retain individual colours I don't see a way round this, although there are some creative problem solvers on here that know a better way. 

This is what I've been doing for outlines, having to sync it for multiple objects is kind of a pain. I think @Aammppaa's suggestion to use symbols should really help with this as well.

 

10 hours ago, Aammppaa said:

In version 2: You can use a Symbol to keep your Composite Body and Composite Mask in Sync. Doesn't solve the banding on the gradient though.

Didn't know about symbols, I just watched a short video about them and they seem to be a great way to bypass the issue (and as a bonus to keep lineart in sync)!

Color banding can be solved by not grouping the inner shapes, since in my experience it's caused by the pass-through rendering of the group. It should be easy enough to use the compound path symbol as a mask for every inner shape since they will automatically sync through the symbol feature.

I'll be experimenting with symbols later and post any update. Thanks for the help!

[Valerio]

Thanks @Aammppaa, using symbols did the trick!

I made a symbol using the compound path of the body, then duplicated it and used it as a mask for each individual inner shape (shading, belly). I was even able to throw in an outline! No color banding and the shape is nicely kept in sync thanks to the symbol functionality. It's such a simple and yet powerful feature.

[Aammppaa]

Yep, it is a powerful feature.

I can't recall whether it works reliably with Symbols within Symbols... for example a Symbol for the Ear, which then makes changes to both Ears (and all the Masks) at the same time.