Class: Carpet

Inherits:
Object
  • Object
show all
Defined in:
lib/cantor_carpets.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(seed, depth) ⇒ Carpet

Returns a new instance of Carpet.



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# File 'lib/cantor_carpets.rb', line 7

def initialize(seed, depth)
  @seed = seed
  @depth = depth
  compute_carpet
end

Instance Attribute Details

#bits ⇒ Object (readonly)

Returns the value of attribute bits.



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# File 'lib/cantor_carpets.rb', line 5

def bits
  @bits
end

#depth ⇒ Object (readonly)

Returns the value of attribute depth.



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# File 'lib/cantor_carpets.rb', line 5

def depth
  @depth
end

#image ⇒ Object (readonly)

Returns the value of attribute image.



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# File 'lib/cantor_carpets.rb', line 5

def image
  @image
end

#seed ⇒ Object (readonly)

Returns the value of attribute seed.



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# File 'lib/cantor_carpets.rb', line 5

def seed
  @seed
end

Instance Method Details

#calculate_bits(bit_array) ⇒ Object 



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# File 'lib/cantor_carpets.rb', line 23

def calculate_bits(bit_array)
  if bit_array.size == @seed.size
    return @seed
  end

  row_chunk = bit_array.row_size / @seed.row_size
  col_chunk = bit_array.column_size / @seed.column_size

  @seed.each_with_index do |e, index|
    xi = index[0]
    yi = index[1]
    row_range = (row_chunk * xi)...(row_chunk * (xi + 1))
    column_range = (col_chunk * yi)...(col_chunk * (yi + 1))
    if e == 1
      bit_array[row_range, column_range] = calculate_bits(bit_array[row_range, column_range])
    end
  end
  bit_array 
end

#compute_carpet ⇒ Object 



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# File 'lib/cantor_carpets.rb', line 13

def compute_carpet
  @bits = calculate_bits(new_bit_array)
  @image = create_image
end

#create_image ⇒ Object 



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# File 'lib/cantor_carpets.rb', line 43

def create_image
  canvas = PNG::Canvas.new(@seed.column_size ** @depth, 
                           @seed.row_size ** @depth,
                           PNG::Color::White)
  canvas.each do |x, y, color|
    canvas[x, y] = PNG::Color::Black if @bits[-y, x] == 1
  end
  PNG.new(canvas)
end

#new_bit_array ⇒ Object 



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# File 'lib/cantor_carpets.rb', line 18

def new_bit_array
  Array2D.new(@seed.row_size ** @depth, 
              @seed.column_size ** @depth, 0)
end

#write_image(name = 'carpet.png') ⇒ Object 



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# File 'lib/cantor_carpets.rb', line 53

def write_image(name='carpet.png')
  @image.save(name)
end