iOS Retina Assets Test

testassets.rb

require 'fileutils'

path = ARGV[0]
ok = 0
fail = 0

Dir.glob("#{path}/*.png", File::FNM_DOTMATCH) do |f|
  
  unless f.end_with? "@2x.png"
    
    s2_f = File.basename(f, ".png") + "@2x.png";
    s2_f = File.join(path, s2_f)
    
    if File.exist?(s2_f)

      s1_x, s1_y = IO.read(f)[0x10..0x18].unpack('NN')
      s2_x, s2_y = IO.read(s2_f)[0x10..0x18].unpack('NN')

      if s1_x*2 == s2_x && s1_y*2 == s2_y
        ok = ok + 1
      else
        puts "Bad Dimensions: #{s2_f}; Found: #{s2_x}x#{s2_y}; Expected: #{s1_x*2}x#{s1_y*2}"
        fail = fail + 1
      end
      
    else
      
      puts "Missing File: #{s2_f}"
      fail = fail + 1
      
    end
    
  end

end if File.directory?(path)

puts "OK: #{ok}; Fail: #{fail}"

Usage:

$ ruby testassets.rb /Users/karsten.bruns/Desktop/MyAssets