Is it possible to rotate a Node around an arbitrary point in SpriteKit?

Question

Is there a way to rotate a Node in SpriteKit around an arbitrary point? I now I can manipulate the anchorPoint of my Node, but that is not suff

Answer 1

I think the best way to make this work is through two SKNode and joint them with SKPhysicsJointPin (Look at the pin example below)

I tried to hang a door sign (SKSpriteNode) on my door(`SkScene), and would like to rotate around on the hanging spot when someone touch it

What I did is making a 1x1 SKNode with a HUGH mass and disabled it's gravity effects.

var doorSignAnchor = SKSpriteNode(color: myUIColor, size: CGSize(width: 1, height: 1))
doorSignAnchor.physicsBody = SKPhysicsBody(rectangleOf: doorSignAnchor.frame.size)
doorSignAnchor.physicsBody!.affectedByGravity = false // MAGIC PART
doorSignAnchor.physicsBody!.mass = 9999999999 // MAGIC PART

var doorSignNode = SKSpriteNode(imageNamed:"doorSign")
doorSignNode.physicsBody = SKPhysicsBody(rectangleOf: doorSignNode.frame.size)

and created a SKPhysicsJointPin to connect them all

let joint = SKPhysicsJointPin.joint(
      withBodyA:  doorSignAnchor.physicsBody!,
      bodyB: doorSignNode.physicsBody!,
      anchor: doorSignAnchor.position)
mySkScene.physicsWorld.add(joint)

So it will move like actual door sign, rotate around an arbitrary point (doorSignAnchor)

Reference:

• Official document about Sumulating Physics
• How to Make Hanging Chains With SpriteKit Physis Joints