BishBosh.Cartesian.Vector

AUTHOR

Dr. Alistair Ward

DESCRIPTION

Describes a line's magnitude & direction, irrespective of its position; cf. Move.

Data-types

data Vector

The distance between two coordinates.

Instances

Eq Vector

Defined in BishBosh.Cartesian.Vector

Methods

(==) :: Vector -> Vector -> Bool

(/=) :: Vector -> Vector -> Bool

Show Vector

Defined in BishBosh.Cartesian.Vector

Methods

showsPrec :: Int -> Vector -> ShowS

show :: Vector -> String

showList :: [Vector] -> ShowS

NFData Vector

Defined in BishBosh.Cartesian.Vector

Methods

rnf :: Vector -> ()

Opposable Vector

Defined in BishBosh.Cartesian.Vector

Methods

getOpposite :: Vector -> Vector

Orientated Vector

Defined in BishBosh.Cartesian.Vector

Methods

isDiagonal :: Vector -> Bool

isParallel :: Vector -> Bool

isStraight :: Vector -> Bool

Constants

attackVectorsForKnight :: [Vector]

The constant list of attack-vectors for a Knight.

attackVectorsForKing :: [Vector]

The constant list of attack-vectors for a King.

Functions

attackVectorsForPawn :: LogicalColour -> [Vector]

• The list of attack-vectors for a Pawn.
• N.B.: the Pawn's ability to advance without taking, isn't dealt with here.

translate :: Coordinates -> Vector -> Coordinates

Translate the specified coordinates by the specified vector.

maybeTranslate :: Coordinates -> Vector -> Maybe Coordinates

Where legal, translate the specified coordinates by the specified vector.

toMaybeDirection :: Vector -> Maybe Direction

• Where possible, converts the specified vector into a direction.
• Nothing is returned for those vectors which don't translate into a legal direction (e.g. a Knight's move).

Constructor

measureDistance

Arguments

:: Coordinates

Source.

-> Coordinates

Destination.

-> Vector

Construct a vector by measuring the signed distance between source-coordinates & destination.

Predicates

isDiagonal :: Vector -> Bool

Whether the specified vector is at 45 degrees to an edge of the board, i.e. any move a Bishop could make.

isParallel :: Vector -> Bool

Whether the specified vector is parallel to an edge of the board, i.e. any move a Rook could make.

isStraight :: Vector -> Bool

Whether the specified vector is either parallel or at 45 degrees to an edge of the board, i.e. any move a Queen could make.

isPawnAttack :: LogicalColour -> Vector -> Bool

• Whether the specified vector might represent an attack (rather than an advance) by a Pawn.
• CAVEAT: if the move started at the first rank, then it can't be a Pawn, but that's beyond the scope of this module (since a Vector doesn't define absolute coordinates).

isKnightsMove :: Vector -> Bool

Whether the specified vector represents a move a Knight could make.

isKingsMove :: Vector -> Bool

Whether the specified vector represents a move a King could make.

matchesPawnDoubleAdvance :: LogicalColour -> Vector -> Bool

• Whether the specified vector matches a Pawn's initial double-advance move.
• CAVEAT: passing this test doesn't guarantee that it is a Pawn's double-advance move, since the move may not relate to a Pawn, or could be invalid.