HRing_J { ; This thing is capable of generating Herman rings for alpha ; equal to exp(2*pi*i*a), a irrational. ; p1: alpha. p2: c. p3: Orbit trap radius about 0, reciprocal is ; used for infinity. ; Use outside=real, logmap=0, periodicity=0. z=pixel, a=p1, c=p2, r=real(p3), rr=1/r, iter=0, done=0: z2=sqr(z) z=a*z2*(z-c)/(1-c*z) iter=iter+1 IF(lastsqrrr) color=iter IF(color<1) color=1 ELSEIF(color>127) color=127 ENDIF IF(lastsqrrr) color=(iter/maxit)*127 IF(color<1) color=1 ELSEIF(color>127) color=127 ENDIF IF(lastsqr=0) flag=1-flag ENDIF IF(imag(c)<0) flag=1-flag ENDIF IF(flag==1) z=(3+sqr(c)-sqrt(9-10*sqr(c)+sqr(sqr(c))))/(4*c) ENDIF : z2=sqr(z) z=a*z2*(z-c)/(1-c*z) iter=iter+1 IF(lastsqrrr) color=(iter/maxit)*127 IF(color<1) color=1 ELSEIF(color>127) color=127 ENDIF IF(lastsqr=0) flag=1-flag ENDIF IF(imag(c)<0) flag=1-flag ENDIF IF(flag==1) z=(3+sqr(c)-sqrt(9-10*sqr(c)+sqr(sqr(c))))/(4*c) ENDIF : z2=sqr(z) z=a*z2*(z-c)/(1-c*z) iter=iter+1 IF(lastsqrrr) color=(iter/maxit)*127 IF(color<1) color=1 ELSEIF(color>127) color=127 ENDIF IF(lastsqr