Le 11/08/2022 à 06:14, Andrew Bernard a écrit :
Ah yes it is in the postscript area of the source code.
/draw_circle % filled? radius thickness draw_circle
{
setlinewidth % f? r
currentpoint % f? r x0 y0
3 2 roll % f? x0 y0 r
dup 0 rmoveto
0 360 arc closepath
stroke_and_fill?
} bind def
Simple use of 360 degree arc. Answers what I wanted to know.
OK. Out of curiosity, what was the context?
There's a lot of oldish webpages with complex Bezier curve
constructions for circles.
Those must be approximate constructions. It is not mathematically
possible to construct a Bézier curve which is at the same time an exact
circle.
Perhaps a version earlier than Postscript 3 did not have the arc
operator. Otherwise I don't know why you would bother.
I see arc in the PostScript level 2 manual:
https://www.os2site.com/sw/dev/openwatcom/docs/postscript_level_2_reference_manual.pdf
and given it's such a fundamental command, I am pretty sure it has been
there from the beginning.
Best,
Jean
