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wtsnz/Scale Around Anchor Point.swift

Created June 12, 2019 23:45
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Scale transform around anchor point
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Scale Around Anchor Point.swift
func scaleTransform(for view: UIView, scaledBy scale: CGPoint, aroundAnchorPoint relativeAnchorPoint: CGPoint) -> CGAffineTransform {
let bounds = view.bounds
let anchorPoint = CGPoint(x: bounds.width * relativeAnchorPoint.x, y: bounds.height * relativeAnchorPoint.y)
return CGAffineTransform.identity
.translatedBy(x: anchorPoint.x, y: anchorPoint.y)
.scaledBy(x: scale.x, y: scale.y)
.translatedBy(x: -anchorPoint.x, y: -anchorPoint.y)
}
@Wilsonilo
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Thanks for this!
Interesting using translated x 2 to regulate, is this your own inspiration?

@wtsnz
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wtsnz commented Aug 9, 2023

@Wilsonilo That is a very good question... 4 years ago was a long time and I was deep in the context of graphics then so I can't be sure how I came up with it!

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