Re: Math/Geometry Guru anyone?
Re: Math/Geometry Guru anyone?
- Subject: Re: Math/Geometry Guru anyone?
- From: email@hidden
- Date: Wed, 6 Dec 2000 01:20:59 -0500
On Tue, 05 Dec 2000 17:56:14 -0500, Jason Bourque <email@hidden> asked,
>
I a drawing pie charts
<SPAN voice=HomerSimpson> Mmmmm. Pie... </SPAN>
>
in Ilustrator 9 and need an equation to find the
>
intersecting point of a line extended from the center point the length of
>
the radius.
>
>
Diameter 72 pts
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Radius 36 pts
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Center point coordinate 0,0
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Angle of line extended 45
Fortunately, you selected the center coordinates so that the problem matches the
definition of sine and cosine.
{x,y} = { R * cos ( A ), R * sin ( A )}, where R is the radius and A is the
angle. Zero degrees is directly right of the origin, and angles increase
counterclockwise. (So 45 degrees is up and to the right.)
To get sine and cosine functions, get the Satimage osax (included as part of
Smile). Find it at www.osaxen.com or at its vacation home at
<
http://www.tandb.com.au/smile/>
Note that these functions want their arguments as radians. 2 * pi radians = 360
degrees, so to convert degrees to radians, multiply A by 2 * pi / 360. So the
formula is now (for A in degrees),
set {x,y} to { R * cos( A * 2 * pi / 360 ), R * sin( A * 2 * pi / 360 ) }
And don't redefine what pi is! :-)
--
Scott Norton Phone: +1-703-299-1656
DTI Associates, Inc. Fax: +1-703-706-0476
2920 South Glebe Road Internet: email@hidden
Arlington, VA 22206-2768 or email@hidden