Added the interp_at_native keyword argument to BboxImage in order to

dhyams · dhyams · commit 5986b5bb6431 · 2011-11-10T19:15:39.000-05:00
let the user specify that the image should be treated in a Photoshop-like
manner (interpolation only used if the image is being displayed at a non-
native resolution).

The flag is by default enabled, which matches previous behavior of matplotlib.
diff --git a/lib/matplotlib/image.py b/lib/matplotlib/image.py
@@ -1030,13 +1030,21 @@ def __init__(self, bbox,
                  filternorm=1,
                  filterrad=4.0,
                  resample = False,
+                 interp_at_native=True,
                  **kwargs
                  ):
 
         """
         cmap is a colors.Colormap instance
         norm is a colors.Normalize instance to map luminance to 0-1
 
+        interp_at_native is a flag that determines whether or not interpolation should
+        still be applied when the image is displayed at its native resolution.  A common
+        use case for this is when displaying an image for annotational purposes; it is 
+        treated similarly to Photoshop (interpolation is only used when displaying the
+        image at non-native resolutions).
+
+
         kwargs are an optional list of Artist keyword args
         """
 
@@ -1052,6 +1060,7 @@ def __init__(self, bbox,
                                 )
 
         self.bbox = bbox
+        self.interp_at_native = interp_at_native
 
     def get_window_extent(self, renderer=None):
         if renderer is None:
@@ -1127,6 +1136,10 @@ def make_image(self, renderer, magnification=1.0):
 
         numrows, numcols = self._A.shape[:2]
 
+        if not self.interp_at_native and widthDisplay==numcols and heightDisplay==numrows:
+           print "setting interpolation to zero"
+           im.set_interpolation(0)
+
         # resize viewport to display
         rx = widthDisplay / numcols
         ry = heightDisplay  / numrows
