Adjusting entry squares around enemy units


When a unit moves strategically, it is placed on the tactical map of the strategic square it is entering. It can be placed anywhere in the first four rows or columns of the tactical map it is entering. For example, a unit entering from the west can enter anywhere in columns 0 through 3, and a unit entering from the south can enter anywhere in rows 11 through 14. A unit entering from the southwest (that is, moving northeast) can enter either in columns 0 through 3 south of row 7, or in rows 11 through 14 west of column 7. The square in which it enters is controlled with the "Entry Square" text box on the GITM order form.

However, a unit may not enter in a tactical square containing an enemy unit, nor in a tactical square behind an enemy unit (that is, with the enemy unit between its entry square and the map edge). If it attempts to do so, its entry square will be adjusted to a legal square. This is done as follows; if the square where it wishes to enter is not legal, then it will attempt to enter one square closer to the map edge (if it entered at least one row/column into the tactical map), then two squares closer to the map edge (if it entered at least two rows/columns in). If neither of those squares is legal either, then the unit will adjust its entry square side to side until it finds a valid square. Specifically (assuming a unit moving south and entering along the north edge of the board: the rules are parallel for other entry directions):

If a unit requests an entry square in row 0, and the square is not legal, then it looks for an available square anywhere in row 0, except squares 0-0 and 14-0 as they are against the east and west edges of the map.

If a unit requests an entry square in row 1, and the square is not legal, then it looks for an available square in the same column in row 0. If that square is not legal either, then it looks for an available square anywhere in row 0 except 0-0 and 14-0.

If a unit requests an entry square in row 2, and the square is not legal, then it looks for an available square in the same column in row 1.If that square is not legal either, then it looks for an available square anywhere in row 1 except 0-1 and 14-1. It will not check for enemy units in row 0 when considering possible entry squares in row 1.

If a unit requests an entry square in row 3, and the square is not legal, then it looks for an available square in the same column in row 2. If that square is not legal either, then it looks for an available square in the same column in row 1. If that square is not legal either, then it looks for an available square anywhere in row 1 except 0-1 and 14-1. It will not check for enemy units in row 0 when considering possible entry squares in row 1.

In all of those four cases, if the unit cannot find an available square in the row it searches, then it will enter in a randomly selected square in that row that may contain either impassible terrain or an enemy unit. If it was ordered to enter in row 2 or 3, and ends up entering in row 1, then it may enter behind an enemy unit in row 0. Combat will not occur if it enters in a square with an enemy unit.

An enemy unit is deemed to be "behind" an entering unit only if it is in the same row or column where the entering unit is placed. If a unit is entering a tactical square from the west, and is requesting 3-7 as its entry square, then an enemy unit at 2-7 (or 1-7 or 0-7) will cause 3-7 to be an illegal entry square. However, an enemy unit in any row other than 7 (for example, at 2-6 or 1-8 or 0-8) will not do so, and the entering unit will be permitted to enter at 3-7.

After an entry square is adjusted for enemy units, it is adjusted to maintain the correct side of a river or mountain range if that needs to be done. Adjustments for correct side of a river or mountain do not check for enemy units, so a unit could come in behind an enemy unit as a result of this adjustment as well.