I use the code sample from "Capturing Body Motion in 3D"https://developer.apple.com/documentation/arkit/capturing_body_motion_in_3dI use this functionfunc session(_ session: ARSession, didUpdate anchors: [ARAnchor]) {
for anchor in anchors {
guard let bodyAnchor = anchor as? ARBodyAnchor else { continue }
// Update the position of the character anchor's position.
let bodyPosition = simd_make_float3(bodyAnchor.transform.columns.3)
let bodyOrientation = Transform(matrix: bodyAnchor.transform).rotation
characterAnchor.position = bodyPosition + characterOffset
/// Also copy over the rotation of the body anchor, because the skeleton's pose
/// in the world is relative to the body anchor's rotation.
characterAnchor.orientation = bodyOrientation
if let character = character, character.parent == nil {
// Attach the character to its anchor as soon as
// 1. the body anchor was detected and
// 2. the character was loaded.
characterAnchor.addChild(character)
}
}
}Then I add the code to add or update the body joints: /// add or update joint spheres
if let character = character {
if jointSpheres.count <= character.jointNames.count, initalSpheresTransforms.count <= character.jointNames.count {
let remainingSpheresToAdd = initalSpheresTransforms.count - jointSpheres.count
if remainingSpheresToAdd > 0 {
if addSphereInterval < 5 {
addSphereInterval += 1
} else {
addSphereInterval = 0
let sphereToAddIndex = abs(remainingSpheresToAdd - initalSpheresTransforms.count)
let newSphere = CustomSphere(color: .blue, radius: 0.02)
newSphere.transform = initalSpheresTransforms[sphereToAddIndex]
sphereAnchor.addChild(newSphere, preservingWorldTransform: true)
jointSpheres.append(newSphere)
}
}
for i in 0.. let jointName = character.jointName(forPath: character.jointNames[i])
if let transform = bodyAnchor.skeleton.modelTransform(for: jointName) {
let position = bodyPosition + simd_make_float3(transform.columns.3)
jointSpheres[i].position = position
jointSpheres[i].orientation = bodyOrientation
}
}
}At first everything is okay. When the person rotate 180° the roboter follows.But the body joints stays in the same direction. How can I set the correct position of the blue body joints after the rotation?
