Method: Pixelart::Image#circle

Defined in:
lib/pixelart/circle.rb

#circle ⇒ Object 



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# File 'lib/pixelart/circle.rb', line 10

def circle
  ### for radius use min of width / height
  r = [@img.width, @img.height].min / 2

  center_x = width  / 2
  center_y = height / 2

  ################
  #  try with 96x96
  #    center_x:  96 / 2 = 48
  #    center_y:  96 / 2 = 48
  #
  #     r:    96 / 2 = 48

  img = Image.new( @img.width, @img.height )

  @img.width.times do |x|
    @img.height.times do |y|

      ## change to float calcuation (instead of ints) - why? why not?
      xx, yy, rr = x - center_x,
                   y - center_y,
                   r

      img[ x, y] = if xx*xx+yy*yy < rr*rr
                         @img[ x, y ]
                   else
                         0  ## transparent - alpha(0)
                   end
    end
  end

  img
end