Axes.draw rearranged to support rasterization

leejjoon · leejjoon · commit 18d19b7af6c7 · 2009-12-11T16:57:46.000Z
svn path=/trunk/matplotlib/; revision=8022
diff --git a/lib/matplotlib/axes.py b/lib/matplotlib/axes.py
@@ -30,6 +30,8 @@
 import matplotlib.ticker as mticker
 import matplotlib.transforms as mtransforms
 
+from operator import itemgetter
+
 iterable = cbook.iterable
 is_string_like = cbook.is_string_like
 is_sequence_of_strings = cbook.is_sequence_of_strings
@@ -1698,11 +1700,22 @@ def draw(self, renderer=None, inframe=False):
             artists.extend(self.spines.itervalues())
 
 
+
         dsu = [ (a.zorder, a) for a in artists
                 if not a.get_animated() ]
-        dsu.sort(key=lambda x: x[0])
 
 
+        # add images to dsu if the backend support compositing.
+        # otherwise, does the manaul compositing  without adding images to dsu.
+        if len(self.images)<=1 or renderer.option_image_nocomposite():
+            dsu.extend([(im.zorder, im) for im in self.images])
+            _do_composite = False
+        else:
+            _do_composite = True
+
+
+        dsu.sort(key=itemgetter(0))
+
         # rasterize artists with negative zorder
         # if the minimum zorder is negative, start rasterization
         rasterization_zorder = self._rasterization_zorder
@@ -1719,11 +1732,7 @@ def draw(self, renderer=None, inframe=False):
         if self.axison and self._frameon:
             self.patch.draw(renderer)
 
-        if len(self.images)<=1 or renderer.option_image_nocomposite():
-            for im in self.images:
-                dsu.append( (im.zorder, im) )
-            dsu.sort(key=lambda x: x[0]) # re-sort with images now
-        else:
+        if _do_composite:
             # make a composite image blending alpha
             # list of (mimage.Image, ox, oy)
 
