ItemStack Data Components

General¶

Below is the current set of available Data Components for ItemStacks that are supported with documentation about their function and format.

Attribute Modifiers¶

Any ItemStack can have Attributes added onto it with the accessories:attributes Item Component. It is composed from a list of attribute entries similar to Minecraft's default implementation. Below is an example:

{
    "accessories:attributes": {
        "modifiers": [
            {
                "type": "minecraft:attack_damage",
                "id": "example:increased_damage_boost",
                "amount": 1,
                "operation": "add_value",
                "slot_name": "hat",
                "is_stackable": false,
            }
        ]
    }
}

Field	Usage
`"type"`	Refers to the attribute type that should be adjusted with the given modifier data. This can either be a slot attribute or a registered slot.
`"id"`	The unique resource location to identify this modifier
`"amount"`	The amount of change from the modifier
`"operation"`	The type of calculation operation that should be performed out of the valid values.
`"slot_name"`	Specify a slot to add a strict requirement to where the accessory must be equipped for the effect to apply. Use `"any"` to allow for the attribute to be applied to whatever slot the given item can be equipped into.
`"is_stackable"`	Allows for additional copies of the attribute to function together as a compounding effect

Stacking Attributes

If the given attribute entry is desired to be stacked with other equipped accessory it may be good to use "is_stackable" which indicates that the given "id" passed should be appended with slot information to allow.

Slot Validation¶

Any ItemStack can define invalid or valid slots to which it can be equipped to using the accessories:slot_validation Item Component. Using it allows you to add to or override the equipability for an existing Accessory.

{
    "accessories:slot_validation": {
        "valid_slot": [
            "hat"
        ]
        "invalid_slot": [
            "shoes"
        ]
    }
}

Field	Usage
`"valid_slots"`	An array of string values of valid slots that the stack can be equipped into
`"invalid_slots"`	An array of string values of invalid slots that the stack can not be equipped into

Stack Size¶

This Data Component allows you to adjust the max stack size of an Item for a single Accessory Slot. This can be useful in cases where you want to only allow equipping a specific amount of items int it (E.G. heart containers, or consumables). Note that your size override must be smaller than the max stack size of the Item.

{
    "accessories:stack_size": {
        "use_stack_size": false,
        "size_override": 69
    }
}

Field	Usage
`"use_stack_size"`	Use the stack's given max size as the amount allowed to stack to within Accessories
`"size_override"`	The amount that the size should be overridden to instead of stack size

Accessory Nest¶

Accessories has a system that allows for nesting an Accessory within another Accessory. This can only be done explicitly with the API (code), or when creating a new ItemStack that has the nested_accessories Data Component. Example:

{
    "accessories:nested_accessories": {
        "accessories": [
            {
                "id": "minecraft:diamond",
                "count": 1,
                "components": {
                    "accessories:attributes": {
                        "modifiers": [
                            {
                                "type": "minecraft:attack_damage",
                                "id": "example:increased_damage_boost",
                                "amount": 1,
                                "operation": "add_value",
                                "slot_name": "any",
                                "is_stackable": false,
                            }
                        ]
                    }
                }
            }
            {
                "id": "minecraft:emerald",
                "count": 1,
                "components": {
                    "accessories:attributes": {
                        "modifiers": [
                            {
                                "type": "minecraft:attack_speed",
                                "id": "example:increased_damage_speed",
                                "amount": 1,
                                "operation": "add_value",
                                "slot_name": "any",
                                "is_stackable": false,
                            }
                        ]
                    }
                }
            }
        ]
    }
}

Field	Usage
`"accessories"`	A list of `ItemStack`s that have various components and will be used to get Accessory info from when equipping the nest

Nest Equipability

Make sure to remember the equipability of your nest. If your Nested Accessory needs to change its equipability dynamically, you might want to add the Slot Validation component to the nest. Alternatively, just using a tag or Tag Predicate is fine.

Rendering¶

This section covers the various components you can use to adjust certain rendering aspects of Accessories.

Rendering Override¶

Any equippable ItemStack (or Accessory) can have a component called accessories:render_override, which allows you to force enable/disable the default renderer or the armor renderer.

{
    "accessories:render_override": {
        "default_render_override": false,
        "armor_render_override": true
    }
}

Field	Usage
`"default_render_override"`	An optional boolean value indicating if the default render should be used
`"armor_render_override"`	An optional boolean value indicating if the armor render should be used

Rendering Transformations¶

For any Accessory that uses the default renderer: It is possible to use the render_transformations data component to adjust the positioning, rotation, and scale of the rendering. Some examples are wearing a block as a hat, or placing an item on your arm.

{
    "accessories:render_transformations": {
        "disable_default_translations": true,
        "transformations": [
            {
                "type": "translation",
                "value": [-25, 0, 5]
            },
            {
                "type": "axis_rotation",
                "value": {
                    "angle": 90,
                    "axis": [1, 0, 1],
                }
            }
        ]
    }
}

Transformations¶

TranslationRaw RotationAxis RotationScaleTransform ToMatrix

Translates the given rendering position based on the provided offset Vector.

{
    {
        "type": "translation",
        "value": [-25, 0, 5]
    }
}

The "value" should be a vector with the offset being in the x, y, and z format.

Rotates the given rendering based on the given Quarternion provided.

{
    {
        "type": "raw_rotation",
        "value": [-0.323, 0.111, 0, 0.1232]
    }
}

The "value" should be a vector with the rotation being in the x, y, z, and w format.

Rotates the given rendering based on Angle (In Degrees) and Axis vector to rotate around.

{
    {
        "type": "axis_rotation",
        "value": {
            "angle": 90,
            "axis": [1, 0, 1],
        }
    }
}

The "value" needs to be in the structured format with an Angle in Degrees, and an Axis vector in the x, y, and z format.

Scales the size of the rendering based on the given scale Vector.

{
    {
        "type": "scale",
        "value": [-25, 0, 5]
    }
}

The "value" should be a vector with the offset being in the x, y, and z format.

Transforms the Rendering to the targeted ModelPart name based on the raw positioning Vector or specific Side of the part.

{
    {
        "type": "axis_rotation",
        "value": {
            "model_part": "head",
            "raw_normal": [1, 1, 1],
        }
    }
}

The "value" requires a ModelPart in string format and either the positioning ("raw_normal") Vector as discussed within Rendering API or a specific Side ("side") to translate the rendering to for the given part.

Applies a precomputed matrix to transform the renderer.

{
    {
        "type": "axis_rotation",
        "value": [
            0.99985, -0.01745, 0.00030, 1.00000,  
            0.01745, 0.99970, -0.01745, 1.00000, 
            -0.00000, 0.01745, 0.99985, 1.00000,
            0.00000, 0.00000, 0.00000, 1.00000
        ]
    }
}

The "value" is a list of 16 doubles, representing the values of a 4x4 grid Matrix.

Last update: 2024-12-26