*ô > BLib.Graphic.Circle 1.01 22May1986 0ô v1.00 15Apr1985 Code from Econet front end *ô v1.01 22May1986 Optimised MOVE/PLOTs (: 2: < ô PROCcircle - draw a circle F ô -------------------------- P(ô x%,y%=centre, r%=radius, f%=filled Z: dÝòcircle(x%,y%,r%,f%) nê step,s,c,xp,yp,xr,s%,k% x'k%=13+72*(f%€1) :ô PLOT action ‚/step=-2*¯/32 :ô Length of each arc Œ4s=µstep :ô Precalculate sin of step –7c=›step :ô Precalculate cosine of step 2xp=r%:yp=0 :ô Set initial position ª8ì x%+r%,y% :ô Move to initial point on edge ´4ã s%=1 ¸ 31 :ô We'll do 31 segments here ¾:xr=xp*c-yp*s :ô Calculate next point on edge Èyp=xp*s+yp*c Ò xp=xr Ü:ç f%:ì x%,y% :ô If filled, extra point at centre æ3ð k%,x%+xp,y%+yp :ô Draw a line or a segment ð$í :ô And again ú8ç f%:ì x%,y% :ô Do final segment back to start ð k%,x%+r%,y% á ÿ