when not using the default tile set, the game starts a bit slow (7 fps on an i3 390M, compared to about 12 fps with the tile set on a different new game.)
a proposed fix is to re-purpose the symbol drawing functions to draw to an inner tile set at the beginning of the game, then load it like the normal tile set. that should require minimal code changes but might offer a speed boost. i'm not sure how significant the difference will be.
