Ruby Quellcode

#============================================================================
# ** Bitmap -> .PNG
#----------------------------------------------------------------------------
# www.66rpg.com
# V 1.1
# 16/04/2010 (DD/MM/YYYY)
#----------------------------------------------------------------------------
# Saves a Bitmap as a .png file.
# 
# Bitmap#make_png([path])
#   Saves the Bitmap to path. Eventually given directories will be created
#   if needed.
#============================================================================
 
class Bitmap
  def make_png(path = 'like')
	Graphics.long_code do 
  	File.makedirs(File.dirname(path))
  	data = Zlib::Png_File.make_png(self)
  	if File.extname(path) != '.png'
    	path += '.png'
  	end
  	File.open(path, 'wb') do |file|
    	file.write(data)
  	end
	end
  end
end
 
module Graphics
  def self.long_code(change_frames = true, &block)
	sleeptime = 2.5
	t = Thread.new do
  	if change_frames
    	loop do
      	sleep(sleeptime)
      	Graphics.update
    	end
  	else
    	loop do
      	sleep(sleeptime)
      	Graphics.update
      	Graphics.frame_count -= 1
    	end
  	end
	end
	result = yield
	t.exit
	t = nil
	return result
  end
end
 
module Zlib
  class Png_File < GzipWriter
	def Png_File.make_png(bitmap)
  	self.open('temp.gz') do |gz|
    	gz.make_png(bitmap)
  	end
  	data = nil
  	GzipReader.open('temp.gz') do |gz|
    	data = gz.read
  	end
  	File.delete('temp.gz')
  	return data
	end
 
	def make_png(bitmap)
  	list = [
    	Png_File.png_header,
    	Png_File.png_ihdr(bitmap),
    	Png_File.png_idat(bitmap),
    	Png_File.png_iend
  	]
  	list.each do |i|
    	write(i)
  	end
	end
 
	# Constants
	PNG_HEADER_ARRAY = [137, 80, 78, 71, 13, 10, 26, 10]
	PNG_HEADER_STRING = PNG_HEADER_ARRAY.pack('C*')
 
	IHDR_SIZE = [13].pack('N')
	IHDR_SIGN = 'IHDR'
	IHDR_DEPTH = [8].pack('C')
	IHDR_COLOR = [6].pack('C')
	IHDR_COMP = [0].pack('C')
	IHDR_FILTER = [0].pack('C')
	IHDR_INTERL = [0].pack('C')
	IHDR_WIDTHHEIGHT = Proc.new {|i| [i].pack('N')}
	IHDR_CRC = Proc.new {|i| [Zlib.crc32(i)].pack('N')}
 
	IDAT_HEADER = "\x49\x44\x41\x54"
	IDAT_COMPDATA = Proc.new {|i| Zlib::Deflate.deflate(i, 8)}
	IDAT_CRC = IHDR_CRC
	IDAT_SIZE = Proc.new {|i| [i.length].pack('N')}
 
	DATA_MAX_ARRAY = 2**28 - 5
 
	IEND_SIZE = [0].pack('N')
	IEND_SIGN = 'IEND'
	IEND_CRC = IDAT_CRC
 
	# Methods
	def self.png_header
  	return PNG_HEADER_STRING.dup
	end
 
	def self.png_ihdr(bitmap)
  	width = IHDR_WIDTHHEIGHT.call(bitmap.width)
  	height = IHDR_WIDTHHEIGHT.call(bitmap.height)
  	string = IHDR_SIGN + width + height + IHDR_DEPTH + IHDR_COLOR + IHDR_COMP + IHDR_FILTER + IHDR_INTERL
  	crc = IHDR_CRC.call(string)
  	return IHDR_SIZE + string + crc
	end
 
	def self.png_idat(bitmap)
  	cdat = IDAT_COMPDATA.call(self.png_make_bitmap_data(bitmap))
  	return IDAT_SIZE.call(cdat) + IDAT_HEADER + cdat + IDAT_CRC.call(IDAT_HEADER + cdat)
	end
 
	def self.png_make_bitmap_data(bitmap)
  	gz = Zlib::GzipWriter.open('hoge.gz')
  	w, h = bitmap.width, bitmap.height
  	data = []
  	0.upto(h) do |y|
    	data.push(0)
    	0.upto(w) do |x|
      	c = bitmap.get_pixel(x, y)
      	data.push(c.red)
      	data.push(c.green)
      	data.push(c.blue)
      	data.push(c.alpha)
      	if data.size > DATA_MAX_ARRAY
        	gz.write(data.pack('C*'))
        	data.clear
      	end
    	end
  	end
  	gz.write(data.pack('C*'))
  	data.clear
  	gz.close
 
  	GC.start
  	data = nil
  	Zlib::GzipReader.open('hoge.gz') do |gz|
    	data = gz.read
  	end
  	File.delete('hoge.gz')
  	return data
	end
 
	def self.png_iend
  	return IEND_SIZE + IEND_SIGN + IEND_CRC.call(IEND_SIGN)
	end
  end
end
 
class File
  def File.makedirs(*dirs)
	verbose = if dirs[-1].is_a? String then false else dirs.pop end
	mode = 0755
	for dir in dirs
  	parent = dirname(dir)
  	next if parent == dir or directory? dir
  	makedirs parent unless directory? parent
  	$stderr.print "mkdir ", dir, "\n" if verbose
  	if basename(dir) != ""
    	begin
      	Dir.mkdir dir, mode
    	rescue SystemCallError
      	raise unless directory? dir
    	end
  	end
	end
  end
end