From:	"Shawn Betts" <hotpulp AT netidea DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: ellipses at an angle
Date:	7 Feb 1997 01:21:36 GMT
Organization:	iSTAR internet Incorporated
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References:	<5d098v$b00 AT nr1 DOT ottawa DOT istar DOT net> <5d7ihn$e1e AT wapping DOT ecs DOT soton DOT ac DOT uk> <5dcq2l$qkm AT oravannahka DOT Helsinki DOT FI>
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In article <5dcq2l$qkm AT oravannahka DOT Helsinki DOT FI>, peuha AT cc DOT helsinki DOT fi (Esa A
E Peuha) wrote:

> Adrian Smith (ams94 AT ecs DOT soton DOT ac DOT uk) wrote:
> 
> : Hi, I think if you use Bresenham's algorithm, or the midpoint algorithm
(which
> : are similar), you should be able to do it.  That can certainly draw
straight
> : lines and circles.
> 
> What exactly do you refer to with "Bresenham's algorithm"? There are
> things called the Bresenham line algorithm and the Bresenham circle
> algorithm, which are used to draw lines and circles, respectively.
> These are rather ingeniously derived algorithms which only use integer
> addition and multiplication by constants, so they are fast and easy to
> program. However, these can *only* draw lines and circles, and so are
> improper answer to question of drawing ellipses. (I could post info
> about how to derive these algorithms, if anyone is interested.)
> 
> --
> Esa Peuha
> student of mathematics at the University of Helsinki
> http://www.helsinki.fi/~peuha/

So does anyone know an algorithm for drawing an ellipse at an angle? I would
be very much interested in seeing the derived algorithms.

Shawn Betts

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