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Adding (perfect) circle shape, radius invariant to rotation.

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there are several complaints about circle made from ellipse not being perfect, meaning the radius will differ slightly depending on rotation angle. Most obvious if you look at 45° angle.

For reference, one of the latest bug reports:


This could easily solved by adding one additional shape: a circle, made of 12 nodes instead of only 4. The "real" circle will be almost rotation invariant.

Almost means that in all tests using up to 256.000^2 pixel canvas size the deviation of radius while rotating this circle was smaller than 1 pixel.

The regular ellipse based circle causes a deviation of up to 12,7px at 65536 px canvas, or 1/5000 or 0,2 *10^-3


Edited by NotMyFault
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  • 4 weeks later...

I don't see a question in your post, but this would make a good Feature Request. Seems like an elegant solution that might involve a lot less work than revising the math of the ellipse tool.

-- Walt

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Yeah, the ellipse tool can stay with its imperfections - it is intentionally not called a circle tool.

Simply adding a new circle tools (based on 12 instead of 4 nodes) will solve the problem several users raised.

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  • 3 months later...

I was able to get fairly accurate results with the Cloud tool, with 12 Bubbles. I checked the result with a star with 12 beams as @NotMyFault advised, as well as with 24 beams, and got a good result. Circle.afdesign


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