TexManager fixes.

anntzer · anntzer · commit 0de8ef5ca296 · 2020-05-13T13:10:37.000+02:00
- Fix calling get_grey with fontsize=None or dpi=None (this would
  previously just pass the string "None" down the stack and crash).
- Fix get_rgba stacking colors and get rid of its cache (the slow part
  is accessing the filesystem in get_grey, just stacking some colors
  should be cheap and not caching the result is also nicer memory-wise).
diff --git a/doc/api/api_changes_3.3/deprecations.rst b/doc/api/api_changes_3.3/deprecations.rst
@@ -137,9 +137,10 @@ This method is deprecated.  Use
 ``SymmetricalScale.InvertedSymmetricalTransform`` are deprecated.  Directly
 access the transform classes from the :mod:`.scale` module.
 
-``TexManager.cachedir``
-~~~~~~~~~~~~~~~~~~~~~~~
-Use `matplotlib.get_cachedir()` instead.
+``TexManager.cachedir``, ``TexManager.rgba_arrayd``
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Use `matplotlib.get_cachedir()` instead for the former; there is no replacement
+for the latter.
 
 Setting `.Line2D`\'s pickradius via `.Line2D.set_picker`
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
diff --git a/lib/matplotlib/texmanager.py b/lib/matplotlib/texmanager.py
@@ -53,7 +53,6 @@ class TexManager:
 
     # Caches.
     texcache = os.path.join(mpl.get_cachedir(), 'tex.cache')
-    rgba_arrayd = {}
     grey_arrayd = {}
 
     font_family = 'serif'
@@ -85,6 +84,11 @@ class TexManager:
     def cachedir(self):
         return mpl.get_cachedir()
 
+    @cbook.deprecated("3.3")
+    @property
+    def rgba_arrayd(self):
+        return {}
+
     @functools.lru_cache()  # Always return the same instance.
     def __new__(cls):
         Path(cls.texcache).mkdir(parents=True, exist_ok=True)
@@ -369,30 +373,25 @@ def make_png(self, tex, fontsize, dpi):
 
     def get_grey(self, tex, fontsize=None, dpi=None):
         """Return the alpha channel."""
+        if not fontsize:
+            fontsize = rcParams['font.size']
+        if not dpi:
+            dpi = rcParams['savefig.dpi']
         key = tex, self.get_font_config(), fontsize, dpi
         alpha = self.grey_arrayd.get(key)
         if alpha is None:
             pngfile = self.make_png(tex, fontsize, dpi)
-            X = mpl.image.imread(os.path.join(self.texcache, pngfile))
-            self.grey_arrayd[key] = alpha = X[:, :, -1]
+            rgba = mpl.image.imread(os.path.join(self.texcache, pngfile))
+            self.grey_arrayd[key] = alpha = rgba[:, :, -1]
         return alpha
 
     def get_rgba(self, tex, fontsize=None, dpi=None, rgb=(0, 0, 0)):
         """Return latex's rendering of the tex string as an rgba array."""
-        if not fontsize:
-            fontsize = rcParams['font.size']
-        if not dpi:
-            dpi = rcParams['savefig.dpi']
-        r, g, b = rgb
-        key = tex, self.get_font_config(), fontsize, dpi, tuple(rgb)
-        Z = self.rgba_arrayd.get(key)
-
-        if Z is None:
-            alpha = self.get_grey(tex, fontsize, dpi)
-            Z = np.dstack([r, g, b, alpha])
-            self.rgba_arrayd[key] = Z
-
-        return Z
+        alpha = self.get_grey(tex, fontsize, dpi)
+        rgba = np.empty((*alpha.shape, 4))
+        rgba[..., :3] = mpl.colors.to_rgb(rgb)
+        rgba[..., -1] = alpha
+        return rgba
 
     def get_text_width_height_descent(self, tex, fontsize, renderer=None):
         """Return width, height and descent of the text."""
