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- Newsgroups: comp.programming
- Path: sparky!uunet!spool.mu.edu!torn!nott!cunews!revcan!geovision!pt
- From: pt@geovision.gvc.com (Paul Tomblin)
- Subject: Fillet Mode
- Message-ID: <C0D2tw.HoK@geovision.gvc.com>
- Reply-To: pt@geovision.gvc.com
- Organization: Not officially GeoVision Systems Inc., Ottawa, Ontario
- References: <BzKv0M.1I3@geovision.gvc.com>,
- Date: Tue, 5 Jan 1993 03:25:07 GMT
- Lines: 39
-
- In article <BzKv0M.1I3@geovision.gvc.com>, I wrote:
- | I'm trying to figure out the algorithm for this, but I thought I'd ask
- | first:
- |
- | I want to generate lines with fillets - ie. line segments joined by
- | fixed-radius arcs. I.e. I'd like to be able to get a user to enter a
- | radius, and then digitize a polyline, and I'd change all the corners to nice
- | arcs.
- |
- | Given: Corner points of a polyline, and a fillet radius
- | Generate: the parameters for the arcs at each corner point (ie. radius,
- | start point, end point, or 3 points that define the arc)
- |
- | If anybody can email an algorithm for this, I'll be happy to share my final
- | code.
-
- I got two really helpful replys via email. I have no idea if people posted
- responses, because my newsfeed went down for 3 weeks soon after asking.
-
- One was from Rich Wells (wells@cdsmn.mn.org), who sent me a description of
- an algorithm in geometric terminology.
-
- Another was from Michael Jones (mtj@babar.asd.sgi.com), who, not suprisingly
- considering where he works, sent me some code that uses SGI mathematical
- libraries. However, it isn't too hard to figure out what the various
- PF.*_VEC3 functions do to 3d vectors - especially if you understand Rich's
- description.
-
- Thanks to both of them. I shall be translating Michael's code into our own
- Geographic Macro Language for this program I'm writing.
-
- If anybody wishes a copy of these responses, or has some other code they'd
- like to share, you can email me.
-
- --
- Paul Tomblin, pt@compass.gvc.com
- (This is not an official opinion of GeoVision Systems Inc.)
- "No matter what you've lost - be it a home, a love, a friend - like the 'Mary
- Ellen Carter' rise again." - Stan Rogers - "Mary Ellen Carter"
-