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 * Spine Runtimes License Agreement
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import type { BoneData } from "./BoneData.js";
import type { BoneLocal } from "./BoneLocal.js";
import { BonePose } from "./BonePose.js";
import { PosedActive } from "./PosedActive.js";

/** The current pose for a bone, before constraints are applied.
 *
 * A bone has a local transform which is used to compute its world transform. A bone also has an applied transform, which is a
 * local transform that can be applied to compute the world transform. The local transform and applied transform may differ if a
 * constraint or application code modifies the world transform after it was computed from the local transform. */
export class Bone extends PosedActive<BoneData, BoneLocal, BonePose> {
	/** The parent bone, or null if this is the root bone. */
	parent: Bone | null = null;

	/** The immediate children of this bone. */
	children = [] as Bone[];

	sorted = false;

	constructor (data: BoneData, parent: Bone | null) {
		super(data, new BonePose(), new BonePose());
		this.parent = parent;
		this.applied.bone = this;
		this.constrained.bone = this;
	}

	/** Make a copy of the bone. Does not copy the {@link #getChildren()} bones. */
	copy (parent: Bone | null): Bone {
		const copy = new Bone(this.data, parent);
		copy.pose.set(this.pose);
		return copy;
	}

}