added support for None for dvipng and removed the sqrt in the hack which I think is wrong

jdh2358 · jdh2358 · commit 44df37768b31 · 2008-05-30T19:21:56.000Z
svn path=/branches/v0_91_maint/; revision=5329
diff --git a/lib/matplotlib/rcsetup.py b/lib/matplotlib/rcsetup.py
@@ -42,6 +42,16 @@ def validate_bool(b):
     else:
         raise ValueError('Could not convert "%s" to boolean' % b)
 
+def validate_bool_maybe_none(b):
+    'Convert b to a boolean or raise'
+    if type(b) is str:
+        b = b.lower()
+    if b=='none': return None
+    if b in ('t', 'y', 'yes', 'on', 'true', '1', 1, True): return True
+    elif b in ('f', 'n', 'no', 'off', 'false', '0', 0, False): return False
+    else:
+        raise ValueError('Could not convert "%s" to boolean' % b)
+
 def validate_float(s):
     'convert s to float or raise'
     try: return float(s)
@@ -339,7 +349,7 @@ def __call__(self, s):
     'text.usetex'         : [False, validate_bool],
     'text.latex.unicode'  : [False, validate_bool],
     'text.latex.preamble' : [[''], validate_stringlist],
-    'text.dvipnghack'     : [False, validate_bool],
+    'text.dvipnghack'     : [None, validate_bool_maybe_none],
     'text.fontstyle'      : ['normal', str],
     'text.fontangle'      : ['normal', str],
     'text.fontvariant'    : ['normal', str],
diff --git a/lib/matplotlib/texmanager.py b/lib/matplotlib/texmanager.py
@@ -334,7 +334,12 @@ def get_grey(self, tex, fontsize=None, dpi=None):
             pngfile = self.make_png(tex, fontsize, dpi)
             X = readpng(os.path.join(self.texcache, pngfile))
 
-            if self._dvipng_hack_alpha or rcParams['text.dvipnghack']:
+            if rcParams['text.dvipnghack'] is not None:
+                hack = rcParams['text.dvipnghack']
+            else:
+                hack = self._dvipng_hack_alpha
+            print 'using hack', hack
+            if hack:
                 # hack the alpha channel
                 # dvipng assumed a constant background, whereas we want to
                 # overlay these rasters with antialiasing over arbitrary
@@ -356,7 +361,9 @@ def get_grey(self, tex, fontsize=None, dpi=None):
                 #
                 # Since the foreground is black (0) and the background is
                 # white (1) this reduces to red = 1-alpha or alpha = 1-red
-                alpha = npy.sqrt(1-X[:,:,0])
+                #alpha = npy.sqrt(1-X[:,:,0]) # should this be sqrt here?
+                alpha = 1-X[:,:,0]
+                
             else:
                 alpha = X[:,:,-1]
 
diff --git a/matplotlibrc.template b/matplotlibrc.template
@@ -147,9 +147,14 @@ numerix      : %(numerix)s  # numpy, Numeric or numarray
                             # beware of package collisions: color, geometry, graphicx,
                             # type1cm, textcomp. Adobe Postscript (PSSNFS) font packages
                             # may also be loaded, depending on your font settings
-#text.dvipnghack     : False  # some versions of dvipng don't handle
-                             # alpha channel properly.  Use True to correct and flush
-                             # ~/.matplotlib/tex.cache before testing
+
+#text.dvipnghack : None      # some versions of dvipng don't handle alpha
+                             # channel properly.  Use True to correct
+                             # and flush ~/.matplotlib/tex.cache
+                             # before testing and False to force
+                             # correction off.  None will try and
+                             # guess based on your dvipng version
+
 #text.markup         : 'plain'  # Affects how text, such as titles and labels, are
                                 # interpreted by default.
                                 # 'plain': As plain, unformatted text
