cvs/fract/julia3.cgi

#!/usr/bin/python

import cgi, Image, ImageDraw, sys
from string import atoi

form= cgi.FieldStorage()

# Image size
if form.has_key('width'):
    width=atoi(form['width'].value)
else:
    width= 570
if form.has_key('height'):
    height=atoi(form['height'].value)
else:
    height= 570

xmax, ymax = width-1, height-1          # Coordinate maximums

inx=max(0, min(atoi(form['image.x'].value), xmax))
iny=max(0, min(atoi(form['image.y'].value), ymax))
debug= form.has_key('debug')

if form.has_key('iter'):
    maxiter=atoi(form['iter'].value)
else:
    maxiter= 270

c1, c2 = (-2+2j), (2-2j)                # Corner coordinates

# Force c1 to be upper left and c2 to be lower right
c1, c2= complex(min(c1.real, c2.real), max(c1.imag, c2.imag)), \
        complex(max(c1.real, c2.real), min(c1.imag, c2.imag))

def constant(x, y):
    creal= (float(x)/xmax)*(c2.real - c1.real)+c1.real
    cimag= (float(y)/ymax)*(c2.imag - c1.imag)+c1.imag
    return complex(creal, cimag)

c= constant(inx, iny)                   # Julia set coordinate

julia= Image.new("L", (width, height))
draw= ImageDraw.Draw(julia)

def drawrect((x1, y1), (x2, y2)):
    color= plot(x1, y1)
    cut= 0
    x, y= x1+1, y1
    while x<=x2:
        if color<>plot(x, y):
            cut= 1
        x= x+1
    x, y= x2, y1+1
    while y<=y2:
        if color<>plot(x, y):
            cut= 1
        y= y+1
    x, y= x2-1, y2
    while x>=x1:
        if color<>plot(x, y):
            cut= 1
        x= x-1
    x, y= x1, y2-1
    while y>y1:
        if color<>plot(x, y):
            cut= 1
        y= y-1
    if x2-x1<=1 or y2-y1<=1:
        return
    if cut:
        if x2-x1 > y2-y1:               # If wider than high
            xc= ((x2-x1)/2)+x1
            drawrect((x1, y1), (xc, y2))
            drawrect((xc, y1), (x2, y2))
        else:                           # if higher than wide
            yc= ((y2-y1)/2)+y1
            drawrect((x1, y1), (x2, yc))
            drawrect((x1, yc), (x2, y2))
    else:
        if not debug:
            draw.rectangle([x1, y1, x2, y2], fill= color)
            if yorig >= 0: # The x axis is visible on image
                # mirror over yorig, but keep within image
                y1m= max(0, min(2*yorig-y1, ymax))
                y2m= max(0, min(2*yorig-y2, ymax))
                x1m= max(0, min(2*xorig-x1, xmax))
                x2m= max(0, min(2*xorig-x2, xmax))
                draw.rectangle([x1m, y1m, x2m, y2m], fill= color)

def plot(x, y):
    z= constant(x, y)
    i= 0
    color= julia.getpixel((x, y))
    if color<>0:
        return color
    while i<maxiter and abs(z)<2:
        z= z**2+c
        i= i+1
    color= 16*i%256
    if i>=maxiter or color==0:
        if debug:
            color= 255
        else:
            color= 1
    try:
        julia.putpixel((x, y), color)
        if yorig >= 0: # The x axis is visible on image
            ym= 2*yorig-y   # ym is y mirrored over yorig
            xm= 2*xorig-x
            if ym >= 0 and ym <= ymax and xm>=0 and xm<=xmax:
                # ym is on the image
                julia.putpixel((xm-1, ym), color)
    except IndexError, the_error:
        print "coord", x, y, xm, ym
        raise IndexError, the_error
    return color

# Initial default values
yfrom= 0
yto= ymax
yorig= -1 # The pixel coordinate of the x axis; negative means not on image
xorig= -1

# Check if we should do mirroring
if c1.imag > 0 and c2.imag < 0: # the x axis is visible
    yorig= int((-c1.imag/(c2.imag-c1.imag))*height) # pixel pos. of x axis
    if c1.imag < abs(c2.imag): # the x axis is closer to top than bottom
        yfrom= yorig # Begin at x axis
    else:
        yto= yorig # End at x axis

if c1.real < 0 and c2.real > 0:
    xorig= int((-c1.real/(c2.real-c1.real))*height)

drawrect((0, yfrom), (xmax, yto))

print "Content-type: image/png"
print
julia.save(sys.stdout, "PNG")
1	#!/usr/bin/python
2
3	import cgi, Image, ImageDraw, sys
4	from string import atoi
5
6	form= cgi.FieldStorage()
7
8	# Image size
9	if form.has_key('width'):
10	width=atoi(form['width'].value)
11	else:
12	width= 570
13	if form.has_key('height'):
14	height=atoi(form['height'].value)
15	else:
16	height= 570
17
18	xmax, ymax = width-1, height-1 # Coordinate maximums
19
20	inx=max(0, min(atoi(form['image.x'].value), xmax))
21	iny=max(0, min(atoi(form['image.y'].value), ymax))
22	debug= form.has_key('debug')
23
24	if form.has_key('iter'):
25	maxiter=atoi(form['iter'].value)
26	else:
27	maxiter= 270
28
29	c1, c2 = (-2+2j), (2-2j) # Corner coordinates
30
31	# Force c1 to be upper left and c2 to be lower right
32	c1, c2= complex(min(c1.real, c2.real), max(c1.imag, c2.imag)), \
33	complex(max(c1.real, c2.real), min(c1.imag, c2.imag))
34
35	def constant(x, y):
36	creal= (float(x)/xmax)*(c2.real - c1.real)+c1.real
37	cimag= (float(y)/ymax)*(c2.imag - c1.imag)+c1.imag
38	return complex(creal, cimag)
39
40	c= constant(inx, iny) # Julia set coordinate
41
42	julia= Image.new("L", (width, height))
43	draw= ImageDraw.Draw(julia)
44
45	def drawrect((x1, y1), (x2, y2)):
46	color= plot(x1, y1)
47	cut= 0
48	x, y= x1+1, y1
49	while x<=x2:
50	if color<>plot(x, y):
51	cut= 1
52	x= x+1
53	x, y= x2, y1+1
54	while y<=y2:
55	if color<>plot(x, y):
56	cut= 1
57	y= y+1
58	x, y= x2-1, y2
59	while x>=x1:
60	if color<>plot(x, y):
61	cut= 1
62	x= x-1
63	x, y= x1, y2-1
64	while y>y1:
65	if color<>plot(x, y):
66	cut= 1
67	y= y-1
68	if x2-x1<=1 or y2-y1<=1:
69	return
70	if cut:
71	if x2-x1 > y2-y1: # If wider than high
72	xc= ((x2-x1)/2)+x1
73	drawrect((x1, y1), (xc, y2))
74	drawrect((xc, y1), (x2, y2))
75	else: # if higher than wide
76	yc= ((y2-y1)/2)+y1
77	drawrect((x1, y1), (x2, yc))
78	drawrect((x1, yc), (x2, y2))
79	else:
80	if not debug:
81	draw.rectangle([x1, y1, x2, y2], fill= color)
82	if yorig >= 0: # The x axis is visible on image
83	# mirror over yorig, but keep within image
84	y1m= max(0, min(2*yorig-y1, ymax))
85	y2m= max(0, min(2*yorig-y2, ymax))
86	x1m= max(0, min(2*xorig-x1, xmax))
87	x2m= max(0, min(2*xorig-x2, xmax))
88	draw.rectangle([x1m, y1m, x2m, y2m], fill= color)
89
90	def plot(x, y):
91	z= constant(x, y)
92	i= 0
93	color= julia.getpixel((x, y))
94	if color<>0:
95	return color
96	while i<maxiter and abs(z)<2:
97	z= z**2+c
98	i= i+1
99	color= 16*i%256
100	if i>=maxiter or color==0:
101	if debug:
102	color= 255
103	else:
104	color= 1
105	try:
106	julia.putpixel((x, y), color)
107	if yorig >= 0: # The x axis is visible on image
108	ym= 2*yorig-y # ym is y mirrored over yorig
109	xm= 2*xorig-x
110	if ym >= 0 and ym <= ymax and xm>=0 and xm<=xmax:
111	# ym is on the image
112	julia.putpixel((xm-1, ym), color)
113	except IndexError, the_error:
114	print "coord", x, y, xm, ym
115	raise IndexError, the_error
116	return color
117
118	# Initial default values
119	yfrom= 0
120	yto= ymax
121	yorig= -1 # The pixel coordinate of the x axis; negative means not on image
122	xorig= -1
123
124	# Check if we should do mirroring
125	if c1.imag > 0 and c2.imag < 0: # the x axis is visible
126	yorig= int((-c1.imag/(c2.imag-c1.imag))*height) # pixel pos. of x axis
127	if c1.imag < abs(c2.imag): # the x axis is closer to top than bottom
128	yfrom= yorig # Begin at x axis
129	else:
130	yto= yorig # End at x axis
131
132	if c1.real < 0 and c2.real > 0:
133	xorig= int((-c1.real/(c2.real-c1.real))*height)
134
135	drawrect((0, yfrom), (xmax, yto))
136
137	print "Content-type: image/png"
138	print
139	julia.save(sys.stdout, "PNG")