module RubyRandimage

RubyRandimage creates a random image with the input values. The image created has a width = num_cells and all the internal squares have a width of 1px The first cell color its used as backgroud color You can set the random seed to create images like an identicon image

Constants

DEFAULT_OPTIONS
VERSION

Public Class Methods

create(options={}) click to toggle source

create a random image svg and return it as a svg string

Example:

>> RubyRandimage.create(options)
=> (String)

@param options [hash] additional options for the image

# File lib/ruby_randimage.rb, line 46
def self.create options={}

  options = DEFAULT_OPTIONS.merge(options)
  
  raise "title is invalid" if options[:title] == nil || options[:title] == ''
  raise "num_cells must be between 2 and 16" if options[:num_cells] < 2 || options[:num_cells] > 16
  raise "symmetry_axes must be a two elemnts array" if options[:symmetry_axes].class != Array || options[:symmetry_axes].count!=2
  raise "colors must be an array with at least two elemments" if options[:colors].class != Array || options[:colors].count < 2
  raise "seed is invalid, must be nil or fixnum" if !options[:seed].nil? && options[:seed].class != Fixnum 

  # generate the cells matrix with colors
  matrix = generate_matrix options[:num_cells], options[:colors], options[:symmetry_axes], options[:seed]

  # generate and return the svg string with matrix values
  return RubyMatrixToSvg.matrix_to_svg options[:title], matrix
end

create_and_save_file(filename, options={}) click to toggle source

create a random image svg and save it to the given filename

Example:

>> RubyRandimage.create_and_save_file('test_identicon.png', options)
=> result (Fixnum)

@param filename [string] the full path and filename to save the image svg to @param options [hash] additional options for the image

# File lib/ruby_randimage.rb, line 28
def self.create_and_save_file filename, options={}

  # create the svg image string
  svg = create(options)

  # save svg to file filename
  File.open(filename, 'wb') { |f| f.write(svg) }

end

Private Class Methods

generate_matrix(num_cells, colors, symmetry_axes, seed = nil) click to toggle source

create a num_cells*num_cells matrix of colors randomly

Example:

>> generate_matrix(8, ["#ffffff", "#ffffff", #ff0000], [true, false])
=> (Array[Array[(String)]])

@param num_cells (Fixnum) number of image cells @param colors (Array) the image colors @param symmetry_axes (Array) the image symmetry_axes [x_axis, y_axis] @param seed (Fixnum) The seed to init the rand object

# File lib/ruby_randimage.rb, line 76
def self.generate_matrix num_cells, colors, symmetry_axes, seed = nil

  # init rand object if seed!=nil
  srand(seed) if ! seed.nil?
  
  # init matrix
  cells = Array.new
  num_cells.times { |i| cells[i] = []}

  # set num_cols and num_rows for the symmetry_axes setted
  num_cols = symmetry_axes[0] ? (num_cells/2.to_f).ceil : num_cells
  num_rows = symmetry_axes[1] ? (num_cells/2.to_f).ceil : num_cells

  # for each cell
  (num_rows*num_cols).to_i.times do |cell|
    
    # cell position at matrix
    cell_x = (cell%num_cols)
    cell_y = (cell/num_cols)

    # random color from colors list
    color = colors[rand(colors.length)]
    
    # fill cell
    cells[cell_y][cell_x] = color

    # mirror cell x_axis
    if symmetry_axes[0] && num_cells - 1 != 2*cell_x
      cells[cell_y][num_cells - cell_x - 1] = color

      # mirror cell x_axis and y_axis
      if symmetry_axes[1] && num_cells -1 != 2*cell_y
        cells[num_cells - cell_y - 1][num_cells - cell_x - 1] = color
      end
    end

    #mirror cell y_axis
    if symmetry_axes[1] && num_cells -1 != 2*cell_y
      cells[ num_cells - cell_y-1 ][cell_x] = color
    end
  end

  # return the matrix of colors
  return cells
end