UIPinchGestureRecognizer. Make zoom in location of fingers, not only center [duplicate]

Answer 1

I did it, this is my final code:

if([gesture state] == UIGestureRecognizerStateBegan) {
    previousScale = 1.0;
    lastPoint = [gesture locationInView:[gesture view]];
}

if (
    [gesture state] == UIGestureRecognizerStateChanged) {

    CGFloat currentScale = [[[gesture view].layer valueForKeyPath:@"transform.scale"] floatValue];

    // Constants to adjust the max/min values of zoom
    const CGFloat kMaxScale = 4.0;
    const CGFloat kMinScale = 1.0;

    CGFloat newScale = 1 -  (previousScale - [gesture scale]); // new scale is in the range (0-1)
    newScale = MIN(newScale, kMaxScale / currentScale);
    newScale = MAX(newScale, kMinScale / currentScale);
    scale = newScale;

    CGAffineTransform transform = CGAffineTransformScale([[gesture view] transform], newScale, newScale);

    [gesture view].transform = transform;

    CGPoint point = [gesture locationInView:[gesture view]];
    CGAffineTransform transformTranslate = CGAffineTransformTranslate([[gesture view] transform], point.x-lastPoint.x, point.y-lastPoint.y);

    [gesture view].transform = transformTranslate;
}