One step affine transform for rotation around a point?

Question

How can I make a Core Graphics affine transform for rotation around a point x,y of angle a, using only a single call to CGAffineTransformMake() plus math.h trig functions su

Answer 1

for Swift 4

print(x, y) // where x,y is the point to rotate around
let degrees = 45.0
let transform = CGAffineTransform(translationX: x, y: y)
    .rotated(by: degrees * .pi / 180)
    .translatedBy(x: -x, y: -y)