added christophs dvipng_hack_alpha import fix

svn path=/trunk/matplotlib/; revision=8482

Author: jdh2358

CXX/WrapPython.h

@@ -44,11 +44,7 @@
 #endif
 
 // Prevent multiple conflicting definitions of swab from stdlib.h and unistd.h
-#if defined(__sun) || defined(sun)
-#if defined(_XPG4)
 #undef _XPG4
-#endif
-#endif
 
 // Python.h will redefine these and generate warning in the process
 #undef _XOPEN_SOURCE

lib/matplotlib/texmanager.py

@@ -91,7 +91,7 @@ class TexManager:
     if not os.path.exists(texcache):
         os.mkdir(texcache)
 
-    _dvipng_hack_alpha = dvipng_hack_alpha()
+    _dvipng_hack_alpha = None
 
     # mappable cache of
     rgba_arrayd = {}
@@ -516,8 +516,11 @@ def get_grey(self, tex, fontsize=None, dpi=None):
             if rcParams['text.dvipnghack'] is not None:
                 hack = rcParams['text.dvipnghack']
             else:
+                if self._dvipng_hack_alpha is None:
+                    self._dvipng_hack_alpha = dvipng_hack_alpha()
                 hack = self._dvipng_hack_alpha
 
+
             if hack:
                 # hack the alpha channel
                 # dvipng assumed a constant background, whereas we want to