- Qt 6.9
- Qt Quick 3D
- QML Types
- Joint
- Qt Quick 3D | Commercial or GPLv3

# Joint QML Type

Defines a node in a skeletal animation hierarchy. More...

Import Statement: | `import QtQuick3D`
Inherits: | Node

- List of all members, including inherited members

## Properties

- index : int
- skeletonRoot : Skeleton

## Detailed Description

A joint is a transformable node inside a Skeleton, used for skeletal animation. It is called a "joint" because it can be seen as a joint between the bones of a skeleton.

All the joints must be contained inside a Skeleton, and each joint must have a skeletonRoot pointing back to that skeleton.

     Skeleton {
         id: qmlskeleton
         Joint {
             id: joint0
             index: 0
             skeletonRoot: qmlskeleton
             Joint {
                 id: joint1
                 index: 1
                 skeletonRoot: qmlskeleton
             }
         }
     }

## Property Documentation

index : int

Specifies the index of this joint. This index value is used in the `JointSemantic` custom geometry attribute.

Note: Index values must be unique within the same Skeleton.

Note: Negative values cannot be assigned.

See also QQuick3DGeometry::addAttribute and Qt Quick 3D - Simple Skinning Example.

skeletonRoot : Skeleton

Specifies the Skeleton that contains this joint.

Note: All the Joints in the Skeleton must have the same skeletonRoot. If not, the animation will be broken.

See also Skeleton.