Merge pull request #582 from dhyams/image_nointerp_native

mdboom · mdboom · commit c3d6010e3b02 · 2012-06-07T07:44:01.000-07:00
add interp_at_native keyword to BboxImage
diff --git a/lib/matplotlib/image.py b/lib/matplotlib/image.py
@@ -1032,13 +1032,21 @@ 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
 
         """
@@ -1054,6 +1062,7 @@ 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:
@@ -1120,13 +1129,16 @@ def make_image(self, renderer, magnification=1.0):
         im.set_resample(self._resample)
 
         l, b, r, t = self.get_window_extent(renderer).extents #bbox.extents
-        widthDisplay = (round(r) + 0.5) - (round(l) - 0.5)
-        heightDisplay = (round(t) + 0.5) - (round(b) - 0.5)
+        widthDisplay = round(r) - round(l)
+        heightDisplay = round(t) - round(b)
         widthDisplay *= magnification
         heightDisplay *= magnification
 
         numrows, numcols = self._A.shape[:2]
 
+        if not self.interp_at_native and widthDisplay==numcols and heightDisplay==numrows:
+           im.set_interpolation(0)
+
         # resize viewport to display
         rx = widthDisplay / numcols
         ry = heightDisplay  / numrows
