class Knight

Knight piece for a game of chess

Public Class Methods

new(color, position) click to toggle source

Initializes a new knight piece with color and position.

@param [String] color A string denoting the color of the piece. @param [Array<Integer>] position An integer array of length 2 denoting the location of the piece on the board.

Calls superclass method ChessPiece::new

# File lib/chess_pieces/knight.rb, line 13
def initialize(color, position)
  @move_tree_template = build_knight_move_tree
  super(color == 'white' ? '♞'.white : '♘', color, position, 3)
end

Public Instance Methods

build_knight_move_tree() click to toggle source

Builds the Knight move tree. The Knight can move in an L shape in any direction as long as the board permits. The permutations given represent the 8 spaces a Knight may move to.

@return [MoveTree] move_tree_template A move tree template for the knight.

# File lib/chess_pieces/knight.rb, line 24
def build_knight_move_tree
  move_tree = MoveTree.new([0, 0])
  # Get all possible net changes for a knight
  knight_moves_delta = [1, -1, 2, -2].permutation(2).reject { |n| n.sum.zero? }
  knight_moves_delta.each { |move| move_tree.root.add_child(move) }

  move_tree
end