This is the programming guide to the Multilayer sticker projection system in Mutable, intended to complement the guide for artists and designers Multilayer projection on switchable parts. It also contains an optimization section at the end.
The new Multilayer system in Mutable introduces a new concept, ranged parameters (multi-value parameters). Whereas a normal parameter can only have one value, ranged parameters can have up to N values. You can think of them as an array of N values, all related to the same parameter, and you can access them with an index that goes from 0 to N - 1.
For the programmer's convenience, when using the "Group Projector Parameter" node Mutable manage nearly everything. It will automatically create several ranged parameters to control the stickers, and the programmer will only have to set their values to create the desired sticker design over the character.