cvs/fract/mandel.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

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))

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

def drawrect((x1, y1), (x2, y2)):
    "Draw a rectangle defined by the corners (x1, y1) and (x2, y2)."
    color= plot(x1, y1) # Plot the upper left corner
    # Should we cut this rectangle and recurse into the pieces?
    cut= 0
    ## Plot the edges and at the same time check if they are all the
    ## same color.
    # Upper edge (left to right)
    x, y= x1+1, y1
    while x<=x2:
        if color<>plot(x, y):
            cut= 1
        x= x+1
    # Right edge (top to bottom)
    x, y= x2, y1+1
    while y<=y2:
        if color<>plot(x, y):
            cut= 1
        y= y+1
    # Bottom edge (right to left)
    x, y= x2-1, y2
    while x>=x1:
        if color<>plot(x, y):
            cut= 1
        x= x-1
    # Left edge (bottom to top)
    x, y= x1, y2-1
    while y>y1:
        if color<>plot(x, y):
            cut= 1
        y= y-1
    # If our rectangle is too small to have an inside, we have now
    # plotted every pixel in it.
    if x2-x1<=1 or y2-y1<=1:
        return
    if cut:                             # If we're cutting the rectangle
        if x2-x1 > y2-y1:               # If it's wider than high
            # Cut vertically
            xc= ((x2-x1)/2)+x1
            drawrect((x1, y1), (xc, y2))
            drawrect((xc, y1), (x2, y2))
        else:                           # if it's higher than wide
            # Cut horizontally
            yc= ((y2-y1)/2)+y1
            drawrect((x1, y1), (x2, yc))
            drawrect((x1, yc), (x2, y2))
    else:
        # If we're not cutting, it was the same color along the edge
        if not debug:
            # Fill in the rectangle
            draw.rectangle([x1, y1, x2, y2], fill= color)
            if yorig >= 0: # The x axis is visible on image
                # Fill in the mirror rectangle
                # Mirror y1 and y2 over yorig, but keep within image
                y1m= max(0, min(2*yorig-y1, ymax))
                y2m= max(0, min(2*yorig-y2, ymax))
                draw.rectangle([x1, y1m, x2, y2m], fill= color)

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)

def plot(x, y):
    c= constant(x, y)
    z= i= 0
    color= mandel.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:
        mandel.putpixel((x, y), color)
        if yorig >= 0: # The x axis is visible on image
            ym= 2*yorig-y   # ym is y mirrored over yorig
            if ym >= 0 and ym <= ymax:
                # ym is on the image
                mandel.putpixel((x, 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

# 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

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

print "Content-type: image/png"
print
mandel.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			# 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			debug= form.has_key('debug')
21
22			if form.has_key('iter'):
23			maxiter=atoi(form['iter'].value)
24			else:
25			maxiter= 270
26
27			c1, c2 = (-2+2j), (2-2j) # Corner coordinates
28
29			# Force c1 to be upper left and c2 to be lower right
30			c1, c2= complex(min(c1.real, c2.real), max(c1.imag, c2.imag)), \
31			complex(max(c1.real, c2.real), min(c1.imag, c2.imag))
32
33			mandel= Image.new("L", (width, height))
34			draw= ImageDraw.Draw(mandel)
35
36			def drawrect((x1, y1), (x2, y2)):
37			"Draw a rectangle defined by the corners (x1, y1) and (x2, y2)."
38			color= plot(x1, y1) # Plot the upper left corner
39			# Should we cut this rectangle and recurse into the pieces?
40			cut= 0
41			## Plot the edges and at the same time check if they are all the
42			## same color.
43			# Upper edge (left to right)
44			x, y= x1+1, y1
45			while x<=x2:
46			if color<>plot(x, y):
47			cut= 1
48			x= x+1
49			# Right edge (top to bottom)
50			x, y= x2, y1+1
51			while y<=y2:
52			if color<>plot(x, y):
53			cut= 1
54			y= y+1
55			# Bottom edge (right to left)
56			x, y= x2-1, y2
57			while x>=x1:
58			if color<>plot(x, y):
59			cut= 1
60			x= x-1
61			# Left edge (bottom to top)
62			x, y= x1, y2-1
63			while y>y1:
64			if color<>plot(x, y):
65			cut= 1
66			y= y-1
67			# If our rectangle is too small to have an inside, we have now
68			# plotted every pixel in it.
69			if x2-x1<=1 or y2-y1<=1:
70			return
71			if cut: # If we're cutting the rectangle
72			if x2-x1 > y2-y1: # If it's wider than high
73			# Cut vertically
74			xc= ((x2-x1)/2)+x1
75			drawrect((x1, y1), (xc, y2))
76			drawrect((xc, y1), (x2, y2))
77			else: # if it's higher than wide
78			# Cut horizontally
79			yc= ((y2-y1)/2)+y1
80			drawrect((x1, y1), (x2, yc))
81			drawrect((x1, yc), (x2, y2))
82			else:
83			# If we're not cutting, it was the same color along the edge
84			if not debug:
85			# Fill in the rectangle
86			draw.rectangle([x1, y1, x2, y2], fill= color)
87			if yorig >= 0: # The x axis is visible on image
88			# Fill in the mirror rectangle
89			# Mirror y1 and y2 over yorig, but keep within image
90			y1m= max(0, min(2*yorig-y1, ymax))
91			y2m= max(0, min(2*yorig-y2, ymax))
92			draw.rectangle([x1, y1m, x2, y2m], fill= color)
93
94			def constant(x, y):
95			creal= (float(x)/xmax)*(c2.real - c1.real)+c1.real
96			cimag= (float(y)/ymax)*(c2.imag - c1.imag)+c1.imag
97			return complex(creal, cimag)
98
99			def plot(x, y):
100			c= constant(x, y)
101			z= i= 0
102			color= mandel.getpixel((x, y))
103			if color<>0:
104			return color
105			while i<maxiter and abs(z)<2:
106			z= z**2+c
107			i= i+1
108			color= 16*i%256
109			if i>=maxiter or color==0:
110			if debug:
111			color= 255
112			else:
113			color= 1
114			try:
115			mandel.putpixel((x, y), color)
116			if yorig >= 0: # The x axis is visible on image
117			ym= 2*yorig-y # ym is y mirrored over yorig
118			if ym >= 0 and ym <= ymax:
119			# ym is on the image
120			mandel.putpixel((x, ym), color)
121			except IndexError, the_error:
122			print "coord", x, y, xm, ym
123			raise IndexError, the_error
124			return color
125
126			# Initial default values
127			yfrom= 0
128			yto= ymax
129			yorig= -1 # The pixel coordinate of the x axis; negative means not on image
130
131			# Check if we should do mirroring
132			if c1.imag > 0 and c2.imag < 0: # the x axis is visible
133			yorig= int((-c1.imag/(c2.imag-c1.imag))*height) # pixel pos. of x axis
134			if c1.imag < abs(c2.imag): # the x axis is closer to top than bottom
135			yfrom= yorig # Begin at x axis
136			else:
137			yto= yorig # End at x axis
138
139			drawrect((0, yfrom), (xmax, yto))
140
141			print "Content-type: image/png"
142			print
143			mandel.save(sys.stdout, "PNG")