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Re: Athens and ellipse drawing

Posted by Igor Stasenko on Apr 11, 2014; 8:35pm
URL: https://forum.world.st/Athens-and-ellipse-drawing-tp4754256p4754268.html

yes, you using stroke for 2nd ellipse,
but stroke width is also subject of scaling, that's why it has different width, because
of non-uniform scaling (x/y).
instead you can first, draw a filled ellipse (blue) and then draw green one over it.


On 11 April 2014 21:33, Juraj Kubelka <[hidden email]> wrote:
Hi Igor, hi all!

I am not sure how to properly draw ellipse. Right now I draw a path like this:

The path is created that way:
-=-=-=-=-
computePath
path := self athensCanvas
createPath: [ :builder | 
builder
absolute;
moveTo: 0 @ 0.5;
ccwArcTo: 0.5 @ 0.0 angle: 90 degreesToRadians;
ccwArcTo: 0.0 @ -0.5 angle: 90 degreesToRadians;
ccwArcTo: -0.5 @ 0.0 angle: 90 degreesToRadians;
ccwArcTo: 0 @ 0.5 angle: 90 degreesToRadians ]
-=-=-=-=-

And draw it like this:
-=-=-=-=-
drawOn: athensCanvas
athensCanvas pathTransform
restoreAfter: [ 
athensCanvas pathTransform
scaleBy: rectangle extent asFloatPoint
athensCanvas 
setPaint: color;
drawShape: self path.
  (athensCanvas setStrokePaint: strokePaint) 
width: (self strokeWidth / self scale) asFloat. 
athensCanvas drawShape: self path ]
-=-=-=-=-

But with a different shapes, the border does not have same width all around the ellipse. See the image:


Is there better way to draw it?
Thank you,
Jura



--
Best regards,
Igor Stasenko.
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