%!
% Fractal leaf
% Rehmi & Don

/rnd % limit ==> 0..limit-1
{ random mul floor } def

/fractlevel % granularity branchscale branchangle ==> dict
{
    20 dict begin
    /branchangles exch def
    /branchscale exch def
    /granularity exch def
    currentdict end
} def

/deffractal % [ dict ... ==> dict
{
    counttomark
    null exch
    { 1 index exch /nextlevel exch put } repeat
    exch pop
} def

/drawline {
    newpath
    0 0 moveto
    0 1 lineto
    stroke
} def

/fractal {	% fract ==> ---
    begin
    drawline

    granularity {
	/grain exch def
	0 grain translate

	branchangles {
	    /branchangle exch def

	    gsave
	    branchangle rotate

	    nextlevel null eq not
	    { branchscale scale
	      nextlevel fractal }
    	    { drawline } ifelse

	    grestore
	} forall

	0 grain neg translate

    } for

    pause

    end
} def

/test {
    0 setlinewidth
    288 50 translate
    260 260 scale
    fractlevels fractal
} def

/fractlevels [
    {1 1 1} 
    {branchangle  2 div cos .1 add dup mul .3 add dup  }
    [-110 -60 0 60 110] 
    fractlevel
    {.08 .03 1}
    {grain 110 mul 50 add sin dup mul 7 div dup}
    {[-60 grain 30 mul add  60 grain 30 mul sub]}
    fractlevel
    {.05  100 rnd 1000 div .14 add  1} 
    {.4 grain .3 mul sub dup}
    {[89 grain 85 mul sub		-89 grain 85 mul add
      70 grain 40 mul sub 30 rnd sub	-70 grain 40 mul add 30 rnd add]}
    fractlevel
    {0 1 -1}
    {1 1}
    []
    fractlevel
deffractal def

test