TODO

  Priority:    Med

  Title:       EXAMPLES/NX FONT CACHING
  Description: The font caching logic in examples/nx is incomplete.  Fonts are
               added to the cache, but never removed.  When the cache is full
               it stops rendering.  This is not a problem for the examples/nx
               code because it uses so few fonts, but if the logic were
               leveraged for more general purposes, it would be a problem.
               Update: see examples/nxtext for some improved font cache handling.
  Status:      Open
  Priority:    Low.  This is not really a problem because examples/nx works
               fine with its bogus font caching.

  Title:       EXAMPLES/NXTEXT ARTIFACTS
  Description: examples/nxtext.  Artifacts when the pop-up window is opened.
               There are some artifacts that appear in the upper left hand
               corner.  These seems to be related to window creation.  At
               tiny artifact would not be surprising (the initial window
               should like at (0,0) and be of size (1,1)), but sometimes
               the artifact is larger.
  Status:      Open
  Priority:    Medium.