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I have a CGPath (created by UIBezierPath) which I want to scale to whatever size I want by applying a CGAffineTransformScale.

Does this influence my drawing quality (when converting to an image) and if not, why?

Christian 'fuzi' Orgler
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    I can understand that you may want some other people opinion and some explanation why it does/doesn't. But if you're working with this it may be very easy for you to check if it influence the rendering quality or not :) – pteofil May 04 '15 at 12:59

1 Answers1

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A UIBezierPath isn't a bitmap image. It is a made of coordinates that can be used for multiple operations such as : stroke, fill, hitTest, alphaMask, etc. When scaling your UIBezierPath, you are applying a geometric transformation on those coordinates. You can then perform one of the operations mentioned above using the scaled path and the drawing quality won't have suffered at all.

In other words, drawing using UIBezierPath is analogous to drawing a vectorized image. Those also do not suffer from scaling operations.

What makes image quality suffer is scaling images made of pixels (instead of operations). Then all pixels are scaled indiscriminately because the operations that led to those pixels aren't known anymore. Thus there is no difference between pixels drawn using a stroke and those drawn using a fill. Both will be scaled using the same ratio when they probably shouldn't.

Dalzhim
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