boolean bd_line_shifting_borders; // BD engine uses line-shifting wrap-around
boolean bd_scan_first_and_last_row; // BD engine scans top and bottom border rows
boolean bd_short_explosions; // BD engine uses four game cycles for explosions
boolean bd_line_shifting_borders; // BD engine uses line-shifting wrap-around
boolean bd_scan_first_and_last_row; // BD engine scans top and bottom border rows
boolean bd_short_explosions; // BD engine uses four game cycles for explosions