Path: utzoo!utgpu!attcan!uunet!lll-winken!lll-tis!ames!pasteur!agate!bionet!apple!parent
From: parent@Apple.COM (Sean Parent)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Quickdraw ovals
Summary: Ovals again
Message-ID: <22257@apple.Apple.COM>
Date: 15 Dec 88 23:09:34 GMT
References: <1146@tank.uchicago.edu> <18216@agate.BERKELEY.EDU> <1723@pur-phy> <18307@agate.BERKELEY.EDU>
Organization: Apple Computer Inc., Cupertino, CA
Lines: 32

In article <18307@agate.BERKELEY.EDU>, lippin@russet.berkeley.edu (The Apathist) writes:
> In article <18216@agate.BERKELEY.EDU> I wrote:
> >(While we're at the wishing well, how about fixing FrameOval so that
> >it doesn't leave gaps?)
> 
> Recently parent@Apple.COM (Shean Parent) wrote:
> >The way that QuickDraw draws an oval is to strike an oval inside the
> >given rectangle then inset by the pen size and strike a second oval.
> >The area between the two strikes is filled with the current pen
> >pattern and color. If you think of it like this then it is clear why
> 
> >It is not a bug. It was designed that way.
> 
> Regardless of how it was designed, it doesn't produce the specified
> result, that is, frames of ovals.  Thus, it's a bug.

It does frame the oval it is just that the frame of an oval with a 1,1 pen size
gets so thin that it cannot be rendered. It also has some very nice affects
when it comes to nesting consentric (sp) ovals.

Again it is part of the QD model. If you have a better way to draw an oval that
fits well in the QD model I would like to hear of it (see my previouse post
to see why your suggested method fails). For some applications what is needed
is a different model not just some kludge for ovals.

But QD works quite well and it is fast even if it does have limitations (all
graphics models do).

Sean

P.S. I am not part of the QD team so my opinions are my own and don't reflect
everyone's opinion in the QD team or in Apple (even though I wish they did
:-) ). I work in the PrintShop if anyone cares.