Cylinder Orientation between two points on a sphere, Scenekit, Quaternions IOS

Question

I\'ve been trying to draw a cylinder between two points on the outer edge of a sphere using SceneKit. I have already produced a line between these two points using primitive

Answer 1

i use SCNVector3 extensions with:

 func cylVector(from : SCNVector3, to : SCNVector3) -> SCNNode {
    let vector = to - from,
        length = vector.length()

    let cylinder = SCNCylinder(radius: cylsRadius, height: CGFloat(length))
    cylinder.radialSegmentCount = 6
    cylinder.firstMaterial = material

    let node = SCNNode(geometry: cylinder)

    node.position = (to + from) / 2
    node.eulerAngles = SCNVector3Make(CGFloat(Double.pi/2), acos((to.z-from.z)/length), atan2((to.y-from.y), (to.x-from.x) ))

    return node
}