czuger/rhex

require_relative 'base_hex'

# This class represents an hexagon stored in a cube coordinate system.
#
# Please read http://www.redblobgames.com/grids/hexagons/#coordinates
# to understand what a cube coordinates system is
# The cube class is only for computation.
# It is not intended to be used directly in your program.
#
# @attr_reader [Integer] x the x coordinate of the cube representation of the hexagon
# @attr_reader [Integer] y the y coordinate of the cube representation of the hexagon
# @attr_reader [Integer] z the z coordinate of the cube representation of the hexagon
#
class CubeHex < BaseHex

  attr_reader :x,:y,:z

  # Create an hexagon object
  #
  # @param x [Integer] x coordinate
  # @param y [Integer] y coordinate
  # @param z [Integer] z coordinate
  #
  def initialize( x, y, z, color: nil, border: nil, data: nil )
    @x = x
    @y = y
    @z = z

    super( color, border, data )
  end

  # Transform a cube represented hexagon to an Hexagon::Axial represented hexagon
  #
  # @return [AxialHex] a new AxialHex object
  #
  def to_axial
    AxialHex.new(@x, @z, color: @color, border: @border, data: @data)
  end

  # Round the float coordinates to integer coordinates
  #
  # @return [AxialCube] a new CubeHex object
  #
  def round
    rx=@x.round(0)
    ry=@y.round(0)
    rz=@z.round(0)

    x_diff=(rx-@x).abs
    y_diff=(ry-@y).abs
    z_diff=(rz-@z).abs

    if x_diff > y_diff and x_diff > z_diff
      rx = -ry-rz
    elsif y_diff > z_diff
      ry = -rx-rz
    else
      rz = -rx-ry
    end
    CubeHex.new(rx, ry, rz, color: @color, border: @border, data: @data)
  end

  # Compute the distance between two hexagons (in hexagons)
  #
  # @return [Ingteger] the distance between hex in hexagons
  #
  def distance(h)
    [(@x - h.x).abs, (@y - h.y).abs, (@z - h.z).abs].max
  end

end