scale and center calayer to superview
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When I scale a layer, the result always has origin set at CGPoint(0,0).  What is the best way to make sure after the scale, the layer is still center in its super layer?

[CATransaction begin];

[CATransaction setAnimationDuration: 0];

[CATransaction setDisableActions: TRUE];

self.maskLayer.transform = CATransform3DScale(CATransform3DIdentity, .8, .8,1);

[CATransaction commit];

