Here is a link to a web page with an image:
I used the Epicycloid_Mset formula to make this image. The thickness of the curve is adjusted to be so thick that the curve is filled in and turned into a "lily pad".
The parameter file used to make this image is below:
Autumn_Lilypads { ; Exported from Fracton.
reset=2004 type=formula formulafile=fracton.frm
formulaname=Epicycloid_Mset passes=1 float=y
center-mag=-0.736775091553311/0.2424716796875001/1\
33.333335/1/0/0
params=0.04/0.15/5/30/8/0.25/0/0/0/0 maxiter=500
inside=255 outside=summ
colors=000fOz<28>I0Kz0f<28>O08z88<28>O00zW0<28>c40\
zz0<28>aG00zR<28>0C40zz<28>0CCGGz<28>00O000<12>000\
z88 }
frm:Epicycloid_Mset {
; Epicycloid_Mset based on Astroid_Mset
; Astroid_Mset copyright (c) Paul W. Carlson, 1997
; Epicycloid_Mset by Mike Frazier, 2011
;****************************************************
; Always use floating point math and outside=summ.
;
; Parameters:
; real(p1) = a factor controlling the width of the curves
; imag(p1) = radius of the curve
; real(p2) = number of color ranges
; imag(p2) = number of colors in each color range
; real(p3) = number of cusps, even integers
; imag(p3) = cusp amplitude (0 to 1)
;
; Note that the equation variable is w, not z.
; Initialize cindex to the index of the background color
; Formula modified to avoid color index 0 which can not
; be used with outside=summ in FractInt v20.04
;****************************************************
w=0,
c=pixel,
z=0,
cindex=254,; Background color
bailout=0,
iter=0,
range_num=0,
i=(0,1),
r=imag(p1),
f=real(p3)+1,
b=imag(p3),
;****************************************************
; In the accompanying par file,
; we have 8 color ranges with 30 colors in each range
; for a total of 240 colors. The first range starts at
; color 1. Pixels will use color 254 when |w| > 1000.
; Other values can be used here as long as the product
; of num_ranges times colors_in_range is less than 255.
; Color 254 is reserved for the background color and
; color 255 can be used for the inside color.
;****************************************************
num_ranges=real(p2),
colors_in_range=imag(p2),
;****************************************************
; Real(p1) controls the width of the curves.
; These values will usually be in the range 0.001 to 0.1
;****************************************************
width=real(p1),
index_factor=(colors_in_range-1)/width:
;****************************************************
; The equation being iterated. Almost any equation
; that can be expressed in terms of a complex variable
; and a complex constant will work with this method.
; This example uses the standard Mandelbrot set equation.
;****************************************************
w=w*w+c,
;****************************************************
; The orbit trap curve is an epicycloid.
; Any two-dimensional curve can
; be used which can be expressed in parametric form in
; terms of the angle from the origin.
;****************************************************
ang=atan(imag(w)/real(w)),
astroid=r*(cos(ang)-b*cos(f*ang)+i*(sin(ang)-b*sin(f*ang))),
;****************************************************
; If the orbit point is within some distance of the curve,
; set cindex to the index into the colormap and set the bailout
; flag. Note: the way we use the "distance" here has
; the effect of turning the curves inside-out in the image.
;****************************************************
distance=abs(|w|-|astroid|),
if(distance<width&&iter>1),
cindex=index_factor*distance+range_num*colors_in_range+1,
bailout=1,
endif,
;****************************************************
; Cycle through the range numbers (0 thru num_ranges - 1)
; With two color ranges, even iterations use color
; range 0, odd iterations use color range 1.
;****************************************************
range_num=range_num+1,
if(range_num==num_ranges),
range_num=0,
endif,
;****************************************************
; Since we are using outside=summ, we have to subtract
; the number of iterations from z.
;****************************************************
iter=iter+1,
z=cindex-iter,
;****************************************************
; Finally, we test for bailout
;****************************************************
bailout==0&&|w|<1000
}
--
Mike Frazier
www.fracton.org