forget to update a sprite's tile coordinates when updating its screen
coordinates and only TilePath could be used for sprites in the view and
generally a huge pain was incurred to avoid what isn't very expensive
which is to calculate a sprite's tile coordinates from its screen
coordinates when that sprite is involved in a repaint.
git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@2029 542714f4-19e9-0310-aa3c-eee0fc999fb1
Michael Bayne
5373597143