Each level of the game is layed out using a tile system. The default is 42 tiles wide and 28 tiles tall, but each level can set the tiles if preferred. The number of tiles is fixed, so the size of each tile changes on each device. For example, tiles are twice as wide and tall on an iPad with retina display then on an iPad with an older display. Tiles are always squares.

The screen shots in this directory show the tile system on all four supported devices with an island in the middle of the screen and grid drawing turned on so the tiles are visible.

This grid is very helpful when designing new levels. You can turn it on by changing the valud of DEBUG_DRAW in BridgeColors.h to true.