what we know:
a bird ---- SKSpriteNode
and we want:
bird ------> Parabolic motion
what we do in our code:
touchesBegan{
let path = UIBezierPath()
path.addQuadCurve(to: targetpoint, controlPoint:controlpoint)
bird.run(SKAction.follow(path.cgPath, duration: 0.2))
}
The "follow" action orients the sprite node to the path, so it rotates as it moves. Rotating a rectangle makes it bigger in the X-Y directions. The "frame" property is documented to take this into account:
https://developer.apple.com/documentation/spritekit/sknode
"The frame property provides the bounding rectangle for a node’s visual content, modified by the scale and rotation properties."
