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r2846 | helixhorned | 2012-07-22 04:10:08 -0700 (Sun, 22 Jul 2012) | 5 lines

Prevent integer div-by-0 (SIGFPE) when drawing console background with void tiles.

The tiles used are BIGHOLE (1141) and VIEWBORDER (3250).  Ideally we'd draw the
console background using something specially-coded instead of rotatesprite if
it's fully black anyway.
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