tim@maths.tcd.ie (Timothy Murphy) (11/30/90)
Is there a routine anywhere in QuickDraw, or elsewhere in the Toolbox, for drawing Bezier curves? If not, does anyone have a routine for doing this? Is it best to approximate the curve by a polygon, or to determine the actual pixels? Any suggestions gratefully received. -- Timothy Murphy e-mail: tim@maths.tcd.ie
niko@iastate.edu (Schuessler Nikolaus E) (12/01/90)
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? > I don't think so. >If not, does anyone have a routine for doing this? There is a demo program that does it... who ever wrote it might be willing to give out the source. I have a project due soon that is supposed to do exactly that. If you can grab a copy of the book "Computer Graphics: A programming approach" by Steven Harrington (ISBN 0-07-026751-0) it gives you pseudo code that can be directly converted to pascal code (and adjusted slightly for C). >Is it best to approximate the curve by a polygon, >or to determine the actual pixels? If you make the polygon's sides smaller and smaller until they're the size of a pixel you won't be able to tell that it's a polygon. > >Any suggestions gratefully received. > You're welcome. -- ------------------------------------------------------------------------------ Niko Schuessler "On a two semester mission to engineer where niko@iastate.edu no-one has engineered before.... :-) " ------------------------------------------------------------------------------
minow@mountn.dec.com (Martin Minow) (12/03/90)
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.