Editing item models

Firmament allows you to replace the models of items in a couple of ways.

By SkyBlock ID

Firmament allows you to entirely replace the item model of a SkyBlock item based on its SkyBlock ID. To do this, you can place a model at firmskyblock:<itemid>.

On older versions (before 1.21) Minecraft had system for specifying custom predicates inside of models:

{
    "parent": "minecraft:item/handheld",
    "textures": {
        "layer0": "firmskyblock:item/bat_wand"
    },
    "overrides": [
        {
            "predicate": {
                "firmament:display_name": {
                    "regex": ".*§d.*",
                    "color": "preserve"
                }
            },
            "model": "firmskyblock:item/recombobulated_bat_wand"
        }
    ]
}

Nowadays, these types of overrides / predicate combos are instead seperated out into a client item. The client item is located at <namespace>:items/<itemid>.json, which then references the actual rendered item model in its definition. Firmament supports exclusively for the firmskyblock namespace an automatic conversion from the old format to the new format. Users are nevertheless encouraged to instead of just creating a renderable item model (at firmskyblock:<skyblockid>) to also create a client item definition (at firmskyblock:items/<skyblockid>.json).

That item definition would then reference the actual model file (at any location you want, but i for now have just chosen to reference the default legacy location):

{
    "model": {
        "type": "minecraft:model",
        "model": "firmskyblock:item/<skyblockid>"
    }
}

Note that the inner model refers to any model, so you need to explicitly specify the item/ prefix, which is implicit in the legacy item model system.