Module: Bresenham::Line

Defined in:
lib/bresenham/line.rb

Class Method Summary collapse

Class Method Details

.coordinates(x0, y0, x1, y1) ⇒ Object 



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# File 'lib/bresenham/line.rb', line 3

def self.coordinates(x0, y0, x1, y1)
  dx     = (x1 - x0).abs
  dy     = -(y1 - y0).abs
  step_x = x0 < x1 ? 1 : -1
  step_y = y0 < y1 ? 1 : -1 
  err    = dx + dy
  
  coords = Set.new [[x0, y0]]
  begin
    e2 = 2*err;
    if e2 >= dy
      err += dy
      x0 += step_x
    end
    if e2 <= dx
      err += dx
      y0 += step_y
    end
    coords << [x0, y0]
  end until (x0 == x1 && y0 == y1)
  coords
end