cvs/fract/mandelzoom.cgi

#!/usr/bin/python

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

sys.stderr = sys.stdout

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

# Complex number in center of image is (cx+cy*j)
if form.has_key('cx'):
    cx= atof(form['cx'].value)
else:
    cx= 0

if form.has_key('cy'):
    cy= atof(form['cy'].value)
else:
    cy= 0

if form.has_key('diag'):
    diag= atof(form['diag'].value)
else:
    diag= math.sqrt(8)

debug= form.has_key('debug')

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

#print "Content-Type: text/plain"
#print ""

# If type!=image, then output an HTML page, not an image
if not (form.has_key('type') and form['type'].value == "image"):
    print """Content-Type: text/html

<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<HTML><HEAD>
<TITLE>Mandel Set Zoomer</TITLE>
</HEAD>
<BODY>
<H1>Mandel Set Zoomer</H1>

<FORM ACTION="mandelzoom.cgi" METHOD=GET>

<!-- implies TYPE=SUBMIT -->"""
    print '<INPUT TYPE=IMAGE NAME="image"',
    print 'WIDTH="%s"' % (str(width)),
    print 'HEIGHT="%s"' % (str(height)),
    if debug:
        ds="&debug=on"
    else:
        ds=""
    if form.has_key('zoom'):
        zoom=atoi(form['zoom'].value)
        diag=diag/zoom
    else:
        # If no zoom provided, don't actually zoom
        zoom= 2
    print 'SRC="mandelzoom.cgi?type=image&width=%s&height=%s&iter=%s%s&diag=%s&cx=%s&cy=%s"' % (str(width), str(height), str(maxiter), ds, str(diag), str(cx), str(cy)),
    print 'ALIGN=BOTTOM HEIGHT="%s"' % (str(height)),
    print 'WIDTH="%s"><P>' % (str(width))
    print 'Zoom: <SELECT NAME="zoom">'
    for zv in [-5, -3, -2, 1, 2, 3, 5]:
        print '<OPTION',
        if zv==zoom:
            print 'SELECTED',
        print 'VALUE="%s"' % (str(zv))
        if zv < 0:
            print '>÷%s' % (str(-zv))
        else:
            print '>×%s' % (str(zv))
    print '</SELECT>'
    print """Width: <INPUT TYPE=TEXT NAME="width" MAXLENGTH="4" SIZE="3"
    VALUE="%s">
    Height: <INPUT TYPE=TEXT NAME="height" MAXLENGTH="4" SIZE="3"
    VALUE="%s">
    Iterations: <INPUT TYPE=TEXT NAME="iter" MAXLENGTH="4" SIZE="3"
    VALUE="%s">
    Debug mode: <INPUT TYPE=CHECKBOX NAME="debug" """ % (str(width), str(height), str(maxiter))
    if debug:
        print 'CHECKED>'
    else:
        print '>'
    for key in form.keys():
        if key not in ["zoom", "type", "debug", "image.x", "image.y", "iter", "height", "width"]:
            print '<INPUT TYPE=HIDDEN NAME="%s" VALUE="%s">' % (key, form[key].value)
    print '<INPUT TYPE=HIDDEN NAME=type VALUE="html">'

    print """</FORM>
</BODY></HTML>"""
    sys.exit(0)

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	#!/usr/bin/python
2
3	import cgi, Image, ImageDraw, sys, math
4	from string import atoi, atof
5
6	sys.stderr = sys.stdout
7
8	form= cgi.FieldStorage()
9
10	# Image size
11	if form.has_key('width'):
12	width= atoi(form['width'].value)
13	else:
14	width= 570
15	if form.has_key('height'):
16	height= atoi(form['height'].value)
17	else:
18	height= 570
19
20	xmax, ymax = width-1, height-1 # Coordinate maximums
21
22	# Complex number in center of image is (cx+cy*j)
23	if form.has_key('cx'):
24	cx= atof(form['cx'].value)
25	else:
26	cx= 0
27
28	if form.has_key('cy'):
29	cy= atof(form['cy'].value)
30	else:
31	cy= 0
32
33	if form.has_key('diag'):
34	diag= atof(form['diag'].value)
35	else:
36	diag= math.sqrt(8)
37
38	debug= form.has_key('debug')
39
40	if form.has_key('iter'):
41	maxiter= atoi(form['iter'].value)
42	else:
43	maxiter= 270
44
45	#print "Content-Type: text/plain"
46	#print ""
47
48	# If type!=image, then output an HTML page, not an image
49	if not (form.has_key('type') and form['type'].value == "image"):
50	print """Content-Type: text/html
51
52	<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
53	<HTML><HEAD>
54	<TITLE>Mandel Set Zoomer</TITLE>
55	</HEAD>
56	<BODY>
57	<H1>Mandel Set Zoomer</H1>
58
59	<FORM ACTION="mandelzoom.cgi" METHOD=GET>
60
61	<!-- implies TYPE=SUBMIT -->"""
62	print '<INPUT TYPE=IMAGE NAME="image"',
63	print 'WIDTH="%s"' % (str(width)),
64	print 'HEIGHT="%s"' % (str(height)),
65	if debug:
66	ds="&debug=on"
67	else:
68	ds=""
69	if form.has_key('zoom'):
70	zoom=atoi(form['zoom'].value)
71	diag=diag/zoom
72	else:
73	# If no zoom provided, don't actually zoom
74	zoom= 2
75	print 'SRC="mandelzoom.cgi?type=image&width=%s&height=%s&iter=%s%s&diag=%s&cx=%s&cy=%s"' % (str(width), str(height), str(maxiter), ds, str(diag), str(cx), str(cy)),
76	print 'ALIGN=BOTTOM HEIGHT="%s"' % (str(height)),
77	print 'WIDTH="%s"><P>' % (str(width))
78	print 'Zoom: <SELECT NAME="zoom">'
79	for zv in [-5, -3, -2, 1, 2, 3, 5]:
80	print '<OPTION',
81	if zv==zoom:
82	print 'SELECTED',
83	print 'VALUE="%s"' % (str(zv))
84	if zv < 0:
85	print '>÷%s' % (str(-zv))
86	else:
87	print '>×%s' % (str(zv))
88	print '</SELECT>'
89	print """Width: <INPUT TYPE=TEXT NAME="width" MAXLENGTH="4" SIZE="3"
90	VALUE="%s">
91	Height: <INPUT TYPE=TEXT NAME="height" MAXLENGTH="4" SIZE="3"
92	VALUE="%s">
93	Iterations: <INPUT TYPE=TEXT NAME="iter" MAXLENGTH="4" SIZE="3"
94	VALUE="%s">
95	Debug mode: <INPUT TYPE=CHECKBOX NAME="debug" """ % (str(width), str(height), str(maxiter))
96	if debug:
97	print 'CHECKED>'
98	else:
99	print '>'
100	for key in form.keys():
101	if key not in ["zoom", "type", "debug", "image.x", "image.y", "iter", "height", "width"]:
102	print '<INPUT TYPE=HIDDEN NAME="%s" VALUE="%s">' % (key, form[key].value)
103	print '<INPUT TYPE=HIDDEN NAME=type VALUE="html">'
104
105	print """</FORM>
106	</BODY></HTML>"""
107	sys.exit(0)
108
109	c1, c2 = (-2+2j), (2-2j) # Corner coordinates
110
111	# Force c1 to be upper left and c2 to be lower right
112	c1, c2= complex(min(c1.real, c2.real), max(c1.imag, c2.imag)), \
113	complex(max(c1.real, c2.real), min(c1.imag, c2.imag))
114
115	mandel= Image.new("L", (width, height))
116	draw= ImageDraw.Draw(mandel)
117
118	def drawrect((x1, y1), (x2, y2)):
119	"Draw a rectangle defined by the corners (x1, y1) and (x2, y2)."
120	color= plot(x1, y1) # Plot the upper left corner
121	# Should we cut this rectangle and recurse into the pieces?
122	cut= 0
123	## Plot the edges and at the same time check if they are all the
124	## same color.
125	# Upper edge (left to right)
126	x, y= x1+1, y1
127	while x<=x2:
128	if color<>plot(x, y):
129	cut= 1
130	x= x+1
131	# Right edge (top to bottom)
132	x, y= x2, y1+1
133	while y<=y2:
134	if color<>plot(x, y):
135	cut= 1
136	y= y+1
137	# Bottom edge (right to left)
138	x, y= x2-1, y2
139	while x>=x1:
140	if color<>plot(x, y):
141	cut= 1
142	x= x-1
143	# Left edge (bottom to top)
144	x, y= x1, y2-1
145	while y>y1:
146	if color<>plot(x, y):
147	cut= 1
148	y= y-1
149	# If our rectangle is too small to have an inside, we have now
150	# plotted every pixel in it.
151	if x2-x1<=1 or y2-y1<=1:
152	return
153	if cut: # If we're cutting the rectangle
154	if x2-x1 > y2-y1: # If it's wider than high
155	# Cut vertically
156	xc= ((x2-x1)/2)+x1
157	drawrect((x1, y1), (xc, y2))
158	drawrect((xc, y1), (x2, y2))
159	else: # if it's higher than wide
160	# Cut horizontally
161	yc= ((y2-y1)/2)+y1
162	drawrect((x1, y1), (x2, yc))
163	drawrect((x1, yc), (x2, y2))
164	else:
165	# If we're not cutting, it was the same color along the edge
166	if not debug:
167	# Fill in the rectangle
168	draw.rectangle([x1, y1, x2, y2], fill= color)
169	if yorig >= 0: # The x axis is visible on image
170	# Fill in the mirror rectangle
171	# Mirror y1 and y2 over yorig, but keep within image
172	y1m= max(0, min(2*yorig-y1, ymax))
173	y2m= max(0, min(2*yorig-y2, ymax))
174	draw.rectangle([x1, y1m, x2, y2m], fill= color)
175
176	def constant(x, y):
177	creal= (float(x)/xmax)*(c2.real - c1.real)+c1.real
178	cimag= (float(y)/ymax)*(c2.imag - c1.imag)+c1.imag
179	return complex(creal, cimag)
180
181	def plot(x, y):
182	c= constant(x, y)
183	z= i= 0
184	color= mandel.getpixel((x, y))
185	if color<>0:
186	return color
187	while i<maxiter and abs(z)<2:
188	z= z**2+c
189	i= i+1
190	color= 16*i%256
191	if i>=maxiter or color==0:
192	if debug:
193	color= 255
194	else:
195	color= 1
196	try:
197	mandel.putpixel((x, y), color)
198	if yorig >= 0: # The x axis is visible on image
199	ym= 2*yorig-y # ym is y mirrored over yorig
200	if ym >= 0 and ym <= ymax:
201	# ym is on the image
202	mandel.putpixel((x, ym), color)
203	except IndexError, the_error:
204	print "coord", x, y, xm, ym
205	raise IndexError, the_error
206	return color
207
208	# Initial default values
209	yfrom= 0
210	yto= ymax
211	yorig= -1 # The pixel coordinate of the x axis; negative means not on image
212
213	# Check if we should do mirroring
214	if c1.imag > 0 and c2.imag < 0: # the x axis is visible
215	yorig= int((-c1.imag/(c2.imag-c1.imag))*height) # pixel pos. of x axis
216	if c1.imag < abs(c2.imag): # the x axis is closer to top than bottom
217	yfrom= yorig # Begin at x axis
218	else:
219	yto= yorig # End at x axis
220
221	drawrect((0, yfrom), (xmax, yto))
222
223	print "Content-type: image/png"
224	print
225	mandel.save(sys.stdout, "PNG")