--- fract/mandelzoom.cgi	2001/02/25 20:10:53	1.3
+++ fract/mandelzoom.cgi	2001/02/25 22:54:25	1.5
@@ -38,14 +38,14 @@
 if form.has_key('diag'):
     diag= atof(form['diag'].value)
 else:
-    diag= math.sqrt(8)
+    diag= math.sqrt(32) # sqrt(4**2 + 4**2)
 
 debug= form.has_key('debug')
 
 if form.has_key('iter'):
     maxiter= atoi(form['iter'].value)
 else:
-    maxiter= 240
+    maxiter= 270
 
 # If type!=image, then output an HTML page, not an image
 if not (form.has_key('type') and form['type'].value == "image"):
@@ -69,7 +69,7 @@
     else:
         ds=""
     if form.has_key('zoom'):
-        zoom=atoi(form['zoom'].value)
+        zoom=atof(form['zoom'].value)
         diag=diag/zoom
     else:
         # If no zoom provided, don't actually zoom
@@ -78,9 +78,9 @@
     print 'ALIGN=BOTTOM HEIGHT="%s"' % (str(height)),
     print 'WIDTH="%s"><P>' % (str(width))
     print 'Zoom: <SELECT NAME="zoom">'
-    for zv in [1.0/5, 1.0/3, 1.0/2, 1.0/1.5, 1, 1.5, 2, 3, 5]:
+    for zv in [1.0/5, 1.0/3, 1.0/2, 1.0/1.5, 1.0, 1.5, 2.0, 3.0, 5.0]:
         print '<OPTION',
-        if zv==zoom:
+        if str(zv)==str(zoom):
             print 'SELECTED',
         print 'VALUE="%s"' % (str(zv))
         if zv == 1:
@@ -105,18 +105,29 @@
     else:
         print '>'
     print '<INPUT TYPE=SUBMIT VALUE="Apply">'
-    #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)
-    #for var in [("diag", diag), ("cx", cx), ("cy", cy)]:
-        
+    for var in (("diag", diag), ("cx", cx), ("cy", cy)):
+        print '<INPUT TYPE=HIDDEN NAME="%s" VALUE="%s">' % var
     print '<INPUT TYPE=HIDDEN NAME=type VALUE="html">'
 
     print """</FORM>
 </BODY></HTML>"""
     sys.exit(0)
 
-c1, c2 = (-2+2j), (2-2j)                # Corner coordinates
+# Figure out c1 and c2 from width, height, diag, cx, and cy.
+# Diagonal in pixels
+diagp= math.sqrt(width**2 + height**2)
+# Scale between pixels and coordinates
+scale= diagp/diag
+x= (width/2.0)/scale
+y= (height/2.0)/scale
+
+c1= cx - x + cy - y * (0+1j)
+c2= cx + x + cy + y * (0+1j)
+
+#print width, height, diag, cx, cy, diagp, scale, x, y, c1, c2
+#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)), \