🖌️ Part Tinting

When displaying models of a part, you might find yourself needing to add a tint to your model. You can do that with HammerMultipart.

🪪 PartDefinition

First things first, you must define that your part may have a few "tint slots".

info

Tint slots are not the same as indices, and are dynamically assigned when the PartEntity is placed into a container. Please do keep that in mind when you read tint slot.

To allocate N amount of tint slots, inside your part definition's constructor assign the tintIndexCount to the number of slots you wish to reserve. You don't have to use them all but it is strongly advised against wasting said tint slots to keep memory usage lower.

public class YourPartDefinition extends PartDefinition
{
    public YourPartDefinition()
    {
        this.tintIndexCount = 1;
        ...

🐧 PartEntity

Now when PartEntity is going to be created, you will now have access to multiple tint indices through PartEntity.getTintIndices() (returns int[]) method.

This array is basically a mapping to get tint slot by tint index.

Overriding getTintLayerColor is what actually lets us alter colors.

public class YourPartEntity extends PartEntity
{
    public YourPartEntity(PartDefinition definition, PartContainer container, PartPlacement placement)
    {
        super(definition, container, placement);
    }

    @Override
    public int getTintLayerColor(int tintLayer)
    {
        int[] tintIndices = getTintIndices();
        if(tintLayer == tintIndices[0]) return 0xFF2222;
        return 0xFFFFFF;
    }
}

In this example we transform the tint index 0 on our model into the whatever tint slot the container will have.

Speaking of models, how do tint indices get added?

🪄 JSON Tinting

When making a JSON model (in BlockBench, for example), you may set a "tintindex" property. In our example, we are using tint index 0. In a model it would look something like this:

{
    "parent": "minecraft:block/block",
    "render_type": "cutout",
    "textures": {
        "particle": "yourmod:part/your_part"
    },
    "elements": [
        {
            "name": "w",
            "from": [7, 0, 7],
            "to": [9, 3, 9],
            "rotation": {"angle": 0, "axis": "x", "origin": [8, 2.125, 4.25]},
            "faces": {
                "up": {"uv": [7, 7, 9, 9], "texture": "#particle", "tintindex": 0}
            }
        }
    ]
}

See the "tintindex": 0? That's exactly what makes it tick. Whever a quad has a tint index, it will be transformed into tint slot by HammerMultipart. You then need to handle the given tint slot, which is exactly what we are doing inside of getTintLayerColor method. Transforming tintindex 0 into a red color.