How to animate to rotate counter-clockwise

Just rotate it by whatever angle you did for clockwise, but multiply it by negative one

func rotateLeft() {
    UIView.animate(withDuration: 0.5, animations: {
        self.profileImageView.transform = CGAffineTransform(rotationAngle: ((180.0 * CGFloat(M_PI)) / 180.0) * -1)
        self.profileImageView.transform = CGAffineTransform(rotationAngle: ((0.0 * CGFloat(M_PI)) / 360.0) * -1)
        self.view.layoutIfNeeded()
    })
}

I should also mention that when you say (180.0 * CGFloat(π)) / 180 - You're just saying π, because 180/180 is one.

It looks to me like you're trying to do two different rotations at once? I'm a little confused by that. One thing I've found that really helps is to track the view's axis orientation if you're doing multiple rotations both clockwise and counter-clockwise. Do something like create a property called viewAngle

var viewAngle: CGFloat = 0    // Right-side up to start
let π = CGFloat.pi   // Swift allows special characters hold alt+p to use this, it allows for cleaner code

func rotate(by angle: CGFloat) {

    for i in 0 ..< 4 {
        UIView.animate(withDuration: 0.125, delay: 0.125 * Double(i), options: .curveLinear, animations: {

            self.viewAngle += angle/4
            self.rotateView.transform = CGAffineTransform(rotationAngle: self.viewAngle)
            self.view.layoutIfNeeded()
        }, completion: nil)
    }        

}

If you want to rotate right pass in a positive angle (i.e. π, π/2, π/4, 2*π), or if left pass in a negative angle.

Rotate right by 180 degrees:

rotate(by: π)

Rotate left by 180 degrees:

rotate(by: -π)

EDIT: As you were mentioning, which I didn't see until I tried for myself, when you plug in π or 2π whether it's negative or positive, it just rotates clockwise. To get around this I had to make it rotate by -π/4 increments. So to do a full-circle rotate counter clockwise I did a loop of -π/4 animations if that makes sense. It works, but I feel like there should be an easier way to do this. I would appreciate anyone else chiming in.

How to animate to rotate counter-clockwise

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