* ``fill_color`` - color to use to fill paths with

  - any of the `147 named CSS colors <http://www.w3schools.com/cssref/css_colornames.asp>`_, e.g ``'green'``, ``'indigo'``
  - an RGB(A) hex value, e.g., ``'#FF0000'``, ``'#44444444'``
  - a 3-tuple of integers (r,g,b) between 0 and 255
  - a 4-tuple of (r,g,b,a) where r,g,b are integers between 0..255 and a is between 0..1

* ``fill_alpha`` - floating point between 0 (transparent) and 1 (opaque)
