Class: Gitpaint::PNGRenderer

Inherits:
Array
  • Object
show all
Defined in:
lib/gitpaint/png_renderer.rb

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(png_path) ⇒ PNGRenderer

Returns a new instance of PNGRenderer.



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# File 'lib/gitpaint/png_renderer.rb', line 5

def initialize png_path 
  png = ChunkyPNG::Image.from_file png_path

  png.height.times do |i| 
    self.push(
	  png.row(i).to_a.map do |p|
        self.class.scale self.class.invert self.class.magnitude p
	  end
   	)
  end
end

Class Method Details

.invert(value) ⇒ Object 



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# File 'lib/gitpaint/png_renderer.rb', line 21

def self.invert value 
  256 - value
end

.magnitude(value) ⇒ Object 



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# File 'lib/gitpaint/png_renderer.rb', line 17

def self.magnitude value 
  value / 256 ** 3
end

.scale(value) ⇒ Object 



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# File 'lib/gitpaint/png_renderer.rb', line 25

def self.scale value
  value / (256 / 5)
end