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From: minow@mountn.dec.com (Martin Minow)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Bezier curves in QuickDraw
Keywords: Bezier, Macintosh, Toolbox
Message-ID: <2045@mountn.dec.com>
Date: 3 Dec 90 15:21:23 GMT
References: <1990Nov29.181603.18132@maths.tcd.ie>
Reply-To: minow@bolt.enet.dec.com (Martin Minow)
Organization: Digital Equipment Corporation
Lines: 27

In article <1990Nov29.181603.18132@maths.tcd.ie> tim@maths.tcd.ie
(Timothy Murphy) writes:

>Is there a routine anywhere in QuickDraw, or elsewhere in the Toolbox,
>for drawing Bezier curves?

No.

>If not, does anyone have a routine for doing this?

There was an article in MacTutor last (or last++) year.  Can you get
it in Ireland (we can get Guiness in Boston)?  MacTutor publishes a
yearly collection that is probably worth reading.

Another source might be the recently published book Graphics Gems.

>Is it best to approximate the curve by a polygon,
>or to determine the actual pixels?

I believe that if you export a Bezier curve from a drawing program to
a PICT resource/file, it is written as a polygon with short steps.  That way
the PICT can be scaled without losing too much detail.

Martin Minow
ps: (full disclosure) I've written a few articles for MacTutor, and
Mike Morton, who contributes to comp.sys.mac.programmer has a "gem"
in Graphics Gems.