A question of nomenclature. Should these structures be called threads (or filaments) to distinguish them from the linear structures such as found in the classic mandelbrot? And what could the mandelbrot linear structures be called? Go to http://maxitersfractalfollies.blogspot.com to see what prompts this question. fract234.gif { ; filaments ; blank ; calctime 0:31:17.03 ; created Jun 01, 2010 ; Fractint Version 2004 Patchlevel 9 reset=2004 type=formula formulafile=2circles.frm formulaname=cenx=ceny_jul center-mag=0.0904633/-0.271478/13.83126 params=-0.8416089358195745/-0.2229987487411115/-0.1370891445661794/0.368\ 1142612994781/0.5048982207708976/-0.5791192358165227 float=y maxiter=1500 decomp=256 periodicity=0 cyclerange=0/255 colors=DHVCGUBET9DS8BR7AQ69P57O36N24M13L02K02K13L25M36N47O69P7AQ8CR9DSAE\ TBGUCHVDIWFKXGLYHMZIO_JP`KRaLSbMTcOVePWfQXgRZhS_iTajUbkVclXemYfnZgo_ip`j\ qakrbmscntepufqvgrwhtxiuyjvzjvziuyhsxgrwfqvdoucntblsakr`jq_hpZgoYfnWdmVc\ lUbkT`jS_iRYhQXgPWfNUdMTcLSbKQaJP`IN_HMZGLYEJXDIWCHVBFUAET9DS8BR7AQ58P47\ O36N24M13L02K02K13L25M36N47O69P7AQ8CR9DSAETBGUCHVDIWFKXGLYHMZIO_JP`KRaLS\ bMTcOVePWfQXgRZhS_iTajUbkVclXemYfnZgo_ip`jqakrbmscntepufqvgrwhtxiuyjvzjv\ ziuyhsxgrwfqvdoucntblsakr`jq_hpZgoYfnWdmVclUbkT`jS_iRYhQXgPWfNUdMTcLSbKQ\ aJP`IN_HMZGLYEJXDIWCHVBFUAET9DS8BR7AQ58P47O36N24M13L02K02K13L25M36N47O69\ P7AQ8CR9DSAETBGUCHVDIWFKXGLYHNZIO_JP`KRaLSbMTcOVePWfQYgRZhS_iTajUbkVclXe\ mYfnZho_ip`jqalrbmscntepufqvgswhtxhtxiuyhtxgrwfqveoucntbmsakr`jq_ipZgoYf\ nXdmWclVbkT`iS_hRZgQXfPWeOUdNTcMSbLQaKP`IO_HMZGLYFJXEIW } frm:cenx=ceny_jul { ; Kerry Mitchell 26aug98 ; ; "2 concentric circles" coloring method for Julia sets ; p1 = c = Julia parameter ; p2 = (both) circle center ; real(p3) = x circle radius ; imag(p3) = y circle radius ; bailout hardcoded to 10^12 ; use "decomp=256" coloring ; zc=pixel, c=p1, bailout=1e12, iter=1, rmin=1e12 cenx=p2, radx=real(p3), rad2x=radx*radx ceny=cenx, rady=imag(p3), rad2y=rady*rady: iter=iter+1, zc=sqr(zc)+c tempx=|zc-cenx|-rad2x tempy=|zc-ceny|-rad2y temp=tempx+flip(tempy), r=|temp| if (r<rmin) rmin=r, z=temp endif if ((|zc|>bailout)||(iter==maxit)) iter=-1 endif iter>0 } Roger Alexander _________________________________________________________________ MSN Dating: Find someone special. Start now. http://go.microsoft.com/?linkid=9729707