Thanks for the super detailed reply
Massively helpful as always!
The problem I have with putting different "parts" on different layers is (again, the C2 bane of game making;) because of instance picking of the same objects. I used a container to get around my issues - since using loops to resolve the picking problems because very CPU intensive and I was getting major fps drop with only 15-20 characters (now I can make 60 or 70 before fps starts dropping). Anyway, the issue with having say, an arm or leg on another layer is;
Explaination: I have a "character" who is made up of several components - this "character" however is being created multiple times to create *every* character in the game. Think of it as a "blank" I guess, mannequin? These blank characters can be visualised differently using animations and specific frame settings - so one characters arm might have different colours to another. Changing the outline colour for the layer itself would obviously change the colour for all instances of the "arm" or whatever - which would mean everything would be the same outline colour regardless of intended design/colour. Each arm and leg is made of 10 segments (giving a "noodle" style appearance) with which I can change the appearance/colour/texture of any segment independently. I could have long sleeves or short sleeves for example - requiring a different coloured outline for multiple parts of the same "object".
I think paster may work for all intents and purposes, however I think it may over-complicate what I'm trying to do. I'm also not sure what impact (if any) it will have on performance since there can/will/may be up to 40-50 instances of a "character" present on-screen simultaneously at any given time.
I would just simply "bake" the outline into the graphical content itself, but since there is a form of zordering/rotation to the character, and the limbs are animated using qarp and lerp mathematics - baked outlines would subsequently appear "on top" of stuff that I don't want. If I made a 2nd sprite to match each instance in a container (always placed behind the character) to act as the outline... that would work - but I suspect the extra CPOU overhead for placing instances (to make sure the correct colours are being placed behind the corresponding parts) would cut my fps in half or more.
As is stands, the way my character "blank" is being created already chews up a fair bit of CPU time since it's running a qarp equation for 40 separate parts (per instance of the character) - and I'm not even sure that this will be suitable in the long run. Adding any extra loops (even for basic/simple placement or comparisons) that are related to the character already dramatically affect the performance.
My final resort would be to just ignore the idea of using an outline at all - but it's a look that I particularly like and being able to incorporate it in an elegant manner would be ideal.
Feel free to let me know if you have any thoughts about it - since you're a wizard and all that.
Don't stress about making an example cap though, unless you really want something to do to pass the time - I'm confident I can work out paster with the example pseudo-code you've supplied.
Much appreciated as always!