Class: Circle

Inherits:
Object
  • Object
show all
Defined in:
lib/r2d/circle.rb

Overview

circle.rb gist.github.com/661266

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(radius) ⇒ Circle

Returns a new instance of Circle.



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# File 'lib/r2d/circle.rb', line 7

def initialize radius
  @columns = @rows = radius * 2
  lower_half = (0...radius).map do |y|
    x = Math.sqrt(radius**2 - y**2).round
    right_half = "#{"\xff" * x}#{"\x00" * (radius - x)}"
    "#{right_half.reverse}#{right_half}"
  end.join
  @blob = lower_half.reverse + lower_half
  @blob.gsub!(/./) { |alpha| "\xff\xff\xff#{alpha}"}
end

Instance Attribute Details

#columns ⇒ Object (readonly)

Returns the value of attribute columns.



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# File 'lib/r2d/circle.rb', line 5

def columns
  @columns
end

#rows ⇒ Object (readonly)

Returns the value of attribute rows.



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# File 'lib/r2d/circle.rb', line 5

def rows
  @rows
end

Instance Method Details

#to_blob ⇒ Object 



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# File 'lib/r2d/circle.rb', line 18

def to_blob
  @blob
end