Arm Rotation

Vanilla Rotations

You can set the arm rotation for an item the player is holding! This is done by "wrapping" your model in the rpt:arm_transform model:

{
    "model": {
        "type": "rpt:arm_transform",
        "transform": "item",
        "model": {
            "type": "model",
            "model": "item/diamond_pickaxe"
        }
    }
}

In the example above we specified the arm rotation used in vanilla when the player holds an item. Below is the list of vanilla rotations:

• empty - the player is holding nothing
• item - the player is holding an item that does not trigger any of the rotations below
• block - the player is raising a shield
• bow_and_arrow - the player is drawing a bow
• throw_trident - the player is winding up a trident
• crossbow_charge - the player is loading a crossbow
• crossbow_hold - the player is holding a loaded crossbow
• spyglass - the player is looking through a spyglass
• toot_horn - the player is blowing a goat horn
• brush - the player is using a brush
• spear - the player is using a spear as a kinetic weapon (for 1.21.11 and above)

In addition to vanilla rotations, you can define your own or override some settings of vanilla ones:

Creating a Custom Rotation

{
    "model": {
        "type": "rpt:arm_transform",
        "transform": {
            // rotation along axes
            "x": 0, 
            "y": 0,
            "z": 0,
            "bob": true, // whether to apply the "breathing" animation
            "swing": true, // whether to apply the arm-swing animation while walking
            "type": "item" // vanilla animation type
        },
        "model": { ... }
    }
}

Note

If you specify type in the object above, axis rotations will NOT be applied!

In addition to numbers, axes support expressions (see Math Expressions for details):

{
    "model": {
        "type": "rpt:arm_transform",
        "transform": {
            "x": "sin(time*0.75) * 45 - 90", // The player will wave their hand in front of their face
            "swing": false
        },
        "model": {
            "type": "model",
            "model": "item/bell"
        }
    }
}

RPT also provides some variables you can use:

• time - game time in ticks
• hx/hy/hz - head rotation along axes
• arm - the hand holding the item: 1 for right hand, -1 for left hand

Note

The variables described in Math Expressions will not work inside rpt:arm_transform!

---

Simple Example:

{
    "model": {
        "type": "rpt:arm_transform",
        "transform": {
            "x": "hx - 90",
            "y": "hy",
            "swing": false
        },
        "model": {
            "type": "model",
            "model": "item/diamond_pickaxe"
        }
    }
}