I am trying to convert normal uikit coordinates (top left origin, width and height go right and down) to Sprite Kit coordinates (origin is at center of node, left and down a
According to the docs, SKView has methods for Converting Between View and Scene Coordinates.
Remember the scene is itself an SKNode, so if you need to get from scene coordinates to a particular node coordinate system there's also the methods in Converting to and from the Node’s Coordinate System.