Class: Cell

Inherits:
Array
  • Object
show all
Defined in:
lib/game_2d/game_space.rb

Overview

Cell is a portion of the game space, the exact size of one entity. The cell (0,0) contains subpixel coordinates (0,0) through (399,399).

The behavior I want from Cells is to consider them all unique objects. I want to be able to say “Subtract this set of cells from that set”. Treating Cells as equal if their contents are equal defeats this purpose.

It’s also handy if each Cell knows where it lives in the grid.

Previously, I was using Set as the superclass. That seemed to make sense, since this is an unordered collection. But Set stores everything as hash keys, and hashes get very confused if their keys get mutated without going through the API.

Constant Summary collapse

SORT_BY_REGISTRY = 
->(a,b) { a.registry_id <=> b.registry_id }

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(cell_x, cell_y) ⇒ Cell

Returns a new instance of Cell.



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# File 'lib/game_2d/game_space.rb', line 46

def initialize(cell_x, cell_y)
  @a = []
  @x, @y = cell_x, cell_y
  super(@a)
end

Instance Attribute Details

#x ⇒ Object (readonly)

Returns the value of attribute x.



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# File 'lib/game_2d/game_space.rb', line 36

def x
  @x
end

#y ⇒ Object (readonly)

Returns the value of attribute y.



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# File 'lib/game_2d/game_space.rb', line 36

def y
  @y
end

Instance Method Details

#==(other) ⇒ Object 



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# File 'lib/game_2d/game_space.rb', line 39

def ==(other)
  other.class.equal?(self.class) &&
    other.x == self.x &&
    other.y == self.y &&
    other.instance_variable_get(:@a).sort(&SORT_BY_REGISTRY) == @a.sort(&SORT_BY_REGISTRY)
end

#inspect ⇒ Object 



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# File 'lib/game_2d/game_space.rb', line 53

def inspect; "Cell(#{x}, #{y}) #{@a}"; end

#to_s ⇒ Object 



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# File 'lib/game_2d/game_space.rb', line 52

def to_s; "(#{x}, #{y}) [#{@a.join(', ')}]"; end