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mdboom · mdboom · commit 4e426864216e · 2014-11-24T11:30:21.000-05:00
diff --git a/lib/matplotlib/collections.py b/lib/matplotlib/collections.py
@@ -271,6 +271,12 @@ def draw(self, renderer):
             from matplotlib.patheffects import PathEffectRenderer
             renderer = PathEffectRenderer(self.get_path_effects(), renderer)
 
+        # If the collection is made up of a single shape/color/stroke,
+        # it can be rendered once and blitted multiple times, using
+        # `draw_markers` rather than `draw_path_collection`.  This is
+        # *much* faster for Agg, and results in smaller file sizes in
+        # PDF/SVG/PS.
+
         trans = self.get_transforms()
         facecolors = self.get_facecolor()
         edgecolors = self.get_edgecolor()
