Merge pull request matplotlib#1416 from efiring/mdboom-transparent_pdf_markers

backend_pdf: optional rgbFace arg in fillp replaces code in draw_markers. Closes matplotlib#1410

Author: dmcdougall

lib/matplotlib/backends/backend_pdf.py

@@ -1556,7 +1556,7 @@ def draw_markers(self, gc, marker_path, marker_trans, path, trans, rgbFace=None)
             return
 
         self.check_gc(gc, rgbFace)
-        fillp = gc.fillp()
+        fillp = gc.fillp(rgbFace)
         strokep = gc.strokep()
 
         output = self.file.output
@@ -2002,13 +2002,20 @@ def strokep(self):
         return (self._linewidth > 0 and self._alpha > 0 and
                 (len(self._rgb) <= 3 or self._rgb[3] != 0.0))
 
-    def fillp(self):
+    def fillp(self, *args):
         """
         Predicate: does the path need to be filled?
+
+        An optional argument can be used to specify an alternative
+        _fillcolor, as needed by RendererPdf.draw_markers.
         """
-        return self._hatch or \
-            (self._fillcolor is not None and
-             (len(self._fillcolor) <= 3 or self._fillcolor[3] != 0.0))
+        if len(args):
+            _fillcolor = args[0]
+        else:
+            _fillcolor = self._fillcolor
+        return (self._hatch or
+                (_fillcolor is not None and
+                 (len(_fillcolor) <= 3 or _fillcolor[3] != 0.0)))
 
     def close_and_paint(self):
         """

lib/matplotlib/tests/baseline_images/test_axes/transparent_markers.pdf

@@ -901,6 +901,15 @@ def test_hist_stacked_weighted():
     ax = fig.add_subplot(111)
     ax.hist( (d1, d2), weights=(w1,w2), histtype="stepfilled", stacked=True)
 
+@image_comparison(baseline_images=['transparent_markers'], remove_text=True)
+def test_transparent_markers():
+    np.random.seed(0)
+    data = np.random.random(50)
+
+    fig = plt.figure()
+    ax = fig.add_subplot(111)
+    ax.plot(data, 'D', mfc='none', markersize=100)
+
 if __name__=='__main__':
     import nose
     nose.runmodule(argv=['-s','--with-doctest'], exit=False)