cvs/fract/julia3.cgi

#!/usr/bin/python

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

form= cgi.FieldStorage()

width, height= 570, 570                 # Image size
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	teddy	1.1	#!/usr/bin/python
2
3			import cgi, Image, ImageDraw, sys
4			from string import atoi
5
6			form= cgi.FieldStorage()
7
8			width, height= 570, 570 # Image size
9			xmax, ymax = width-1, height-1 # Coordinate maximums
10
11			inx=max(0, min(atoi(form['image.x'].value), xmax))
12			iny=max(0, min(atoi(form['image.y'].value), ymax))
13			debug= form.has_key('debug')
14
15			if form.has_key('iter'):
16			maxiter=atoi(form['iter'].value)
17			else:
18			maxiter= 270
19
20			c1, c2 = (-2+2j), (2-2j) # Corner coordinates
21
22			# Force c1 to be upper left and c2 to be lower right
23			c1, c2= complex(min(c1.real, c2.real), max(c1.imag, c2.imag)), \
24			complex(max(c1.real, c2.real), min(c1.imag, c2.imag))
25
26			def constant(x, y):
27			creal= (float(x)/xmax)*(c2.real - c1.real)+c1.real
28			cimag= (float(y)/ymax)*(c2.imag - c1.imag)+c1.imag
29			return complex(creal, cimag)
30
31			c= constant(inx, iny) # Julia set coordinate
32
33			julia= Image.new("L", (width, height))
34			draw= ImageDraw.Draw(julia)
35
36			def drawrect((x1, y1), (x2, y2)):
37			color= plot(x1, y1)
38			cut= 0
39			x, y= x1+1, y1
40			while x<=x2:
41			if color<>plot(x, y):
42			cut= 1
43			x= x+1
44			x, y= x2, y1+1
45			while y<=y2:
46			if color<>plot(x, y):
47			cut= 1
48			y= y+1
49			x, y= x2-1, y2
50			while x>=x1:
51			if color<>plot(x, y):
52			cut= 1
53			x= x-1
54			x, y= x1, y2-1
55			while y>y1:
56			if color<>plot(x, y):
57			cut= 1
58			y= y-1
59			if x2-x1<=1 or y2-y1<=1:
60			return
61			if cut:
62			if x2-x1 > y2-y1: # If wider than high
63			xc= ((x2-x1)/2)+x1
64			drawrect((x1, y1), (xc, y2))
65			drawrect((xc, y1), (x2, y2))
66			else: # if higher than wide
67			yc= ((y2-y1)/2)+y1
68			drawrect((x1, y1), (x2, yc))
69			drawrect((x1, yc), (x2, y2))
70			else:
71			if not debug:
72			draw.rectangle([x1, y1, x2, y2], fill= color)
73			if yorig >= 0: # The x axis is visible on image
74			# mirror over yorig, but keep within image
75			y1m= max(0, min(2*yorig-y1, ymax))
76			y2m= max(0, min(2*yorig-y2, ymax))
77			x1m= max(0, min(2*xorig-x1, xmax))
78			x2m= max(0, min(2*xorig-x2, xmax))
79			draw.rectangle([x1m, y1m, x2m, y2m], fill= color)
80
81			def plot(x, y):
82			z= constant(x, y)
83			i= 0
84			color= julia.getpixel((x, y))
85			if color<>0:
86			return color
87			while i<maxiter and abs(z)<2:
88			z= z**2+c
89			i= i+1
90			color= 16*i%256
91			if i>=maxiter or color==0:
92			if debug:
93			color= 255
94			else:
95			color= 1
96			try:
97			julia.putpixel((x, y), color)
98			if yorig >= 0: # The x axis is visible on image
99			ym= 2*yorig-y # ym is y mirrored over yorig
100			xm= 2*xorig-x
101			if ym >= 0 and ym <= ymax and xm>=0 and xm<=xmax:
102			# ym is on the image
103			julia.putpixel((xm-1, ym), color)
104			except IndexError, the_error:
105			print "coord", x, y, xm, ym
106			raise IndexError, the_error
107			return color
108
109			# Initial default values
110			yfrom= 0
111			yto= ymax
112			yorig= -1 # The pixel coordinate of the x axis; negative means not on image
113			xorig= -1
114
115			# Check if we should do mirroring
116			if c1.imag > 0 and c2.imag < 0: # the x axis is visible
117			yorig= int((-c1.imag/(c2.imag-c1.imag))*height) # pixel pos. of x axis
118			if c1.imag < abs(c2.imag): # the x axis is closer to top than bottom
119			yfrom= yorig # Begin at x axis
120			else:
121			yto= yorig # End at x axis
122
123			if c1.real < 0 and c2.real > 0:
124			xorig= int((-c1.real/(c2.real-c1.real))*height)
125
126			drawrect((0, yfrom), (xmax, yto))
127
128			print "Content-type: image/png"
129			print
130			julia.save(sys.stdout, "PNG")