[comp.sys.mac.programmer] Anyone got good arrow-generating code?

rdd@walt.cc.utexas.edu (Robert Dorsett) (02/22/90)

I'm looking for public domain code that will draw *good* arrow tips 
(MacDraw-style barbed arrows) at the end of a line.  Barring that, tips on how 
to pull it off would be helpful.  My current attempts all look rather awful.





Robert Dorsett                                   
Internet: rdd@rascal.ics.utexas.edu               
UUCP: ...cs.utexas.edu!rascal.ics.utexas.edu!rdd  

jackiw@cs.swarthmore.edu (Nick Jackiw) (02/24/90)

rdd@walt.cc.utexas.edu (Robert Dorsett) writes:
> I'm looking for public domain code that will draw *good* arrow tips 
> (MacDraw-style barbed arrows) at the end of a line.  Barring that, tips on how 
> to pull it off would be helpful.  My current attempts all look rather awful.

Rick Flott had a brief note in MacTutor Vol 1, No 9 (duplicated in _The Best
of MacTutor: Volume I_, pp. 174+) on how to do this.  Compute the slope, 
figure out the angle between arrowStart+arrowStop (use PtToAngle), then
PaintArc a rectangle around the endPt  using that angle (or 180 deg from
that angle, I forget) as PaintArc's startAngle and twice the desired arrow
width for PaintArc's arcAngle.


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