add hint for fixing a matplotlib font issue
@@ -11,12 +11,18 @@ has no relation how the DXF formats manages text styles.
The :class:`~ezdxf.entities.Textstyle` entity, the DXF way to define fonts.
The tools in this module provide abstractions to get font measurements with and
-without the optional Matplotlib package.
+without the optional `Matplotlib` package.
For a proper text rendering the font measurements are required. `Ezdxf` has a
lean approach to package dependencies, therefore the rendering results without
support from the optional Matplotlib package are not very good.
+.. hint::
+
+ If `Matplotlib` does not find an installed font and rebuilding the matplotlib
+ font cache does not help, deleting the cache file ``~/.matplotlib/fontlist-v330.json``
+ may help.
+
Font Classes
------------
