Pinch to zoom camera

Question

I\'m trying to make a pinch to zoom camera but I\'m encountering two problems. First is that it allows the user to zoom way too much in and way to much out, secondly when I take

Answer 1

If you need a manual zoomTo(2.0) function, you can use this

// Create listener for Pinch to Zoom
let pinchRecognizer = UIPinchGestureRecognizer(target: self, action:#selector(FSCameraView.pinchToZoom(_:)))
pinchRecognizer.delegate = self
self.previewViewContainer.addGestureRecognizer(pinchRecognizer)

// set the zoom to a zoomed in mode from start
setZoom(CGFloat(2.0)



// and the functions
func pinchToZoom(sender:UIPinchGestureRecognizer) {
    var vZoomFactor = ((sender as! UIPinchGestureRecognizer).scale)
    setZoom(vZoomFactor)
}

func setZoom(zoomFactor:CGFloat) {
    var device: AVCaptureDevice = self.device!
    var error:NSError!
    do{
        try device.lockForConfiguration()
        defer {device.unlockForConfiguration()}
        if (zoomFactor <= device.activeFormat.videoMaxZoomFactor) {

            let desiredZoomFactor:CGFloat = zoomFactor + atan2(sender.velocity, 5.0);
            device.videoZoomFactor = max(1.0, min(desiredZoomFactor, device.activeFormat.videoMaxZoomFactor));
        }
        else {
            NSLog("Unable to set videoZoom: (max %f, asked %f)", device.activeFormat.videoMaxZoomFactor, zoomFactor);
        }
    }
    catch error as NSError{
        NSLog("Unable to set videoZoom: %@", error.localizedDescription);
    }
    catch _{
    }
}