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Ellipse Box calculate perimeter mm2

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wealsh

13 Posts

Posted - Nov 17 2018 : 10:34:17

How to calculate?
like this:

xequte

38185 Posts

Posted - Nov 17 2018 : 17:45:07

Hi

Are fairly close approximation is:

perim := 2 * PI * SqRt(( Sqr( w / 2 ) + Sqr( h / 2 )) / 2 );

Nigel
Xequte Software
www.imageen.com

wealsh

13 Posts

Posted - Nov 18 2018 : 02:49:24

hello
I'm sorry, I don't know much English. Look at the picture. This is the oval

xequte

38185 Posts

Posted - Nov 18 2018 : 14:11:42

What input values do you have? Ellipse width and height?

Nigel
Xequte Software
www.imageen.com

wealsh

13 Posts

Posted - Nov 18 2018 : 21:31:30

ImageEnVect1.GetObjRect(hobj, r);

if (ImageEnVect1.ObjKind[hobj] = iekELLIPSE) then
begin
w:= Trunc((r.Right - r.Left));
h:= Trunc((r.Bottom - r.Top));
end

wealsh

13 Posts

Posted - Nov 19 2018 : 01:49:58

https://www.mathsisfun.com/geometry/ellipse-perimeter.html
https://stackoverflow.com/questions/8433443/modify-a-formula-from-calculating-around-a-circle-to-around-an-oval

delphi can do that ?

xequte

38185 Posts

Posted - Nov 19 2018 : 02:07:55

Area := PI * W * H / 4;
perim := 2 * PI * SqRt(( Sqr( w / 2 ) + Sqr( h / 2 )) / 2 );

Nigel
Xequte Software
www.imageen.com

wealsh

13 Posts

Posted - Nov 19 2018 : 02:39:16

thanks~~

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