RMXP PNG Writer

#===============================================================================
# ** PNG Writer
#===============================================================================

module Zlib
  class PNG_Writer < GzipWriter
#-------------------------------------------------------------------------------
    def make_png(bitmap_Fx,mode)
      @mode = mode
      @bitmap_Fx = bitmap_Fx
      self.write(make_header)
      self.write(make_ihdr)
      self.write(make_idat)
      self.write(make_iend)
    end
#-------------------------------------------------------------------------------
    def make_header
      return [0x89,0x50,0x4e,0x47,0x0d,0x0a,0x1a,0x0a].pack("C*")
    end
#-------------------------------------------------------------------------------
    def make_ihdr
      ih_size = [13].pack("N")
      ih_sign = "IHDR"
      ih_width = [@bitmap_Fx.width].pack("N")
      ih_height = [@bitmap_Fx.height].pack("N")
      ih_bit_depth = [8].pack("C")
      ih_color_type = [6].pack("C")
      ih_compression_method = [0].pack("C")
      ih_filter_method = [0].pack("C")
      ih_interlace_method = [0].pack("C")
      string = ih_sign + ih_width + ih_height + ih_bit_depth + ih_color_type +
               ih_compression_method + ih_filter_method + ih_interlace_method
      ih_crc = [Zlib.crc32(string)].pack("N")
      return ih_size + string + ih_crc
    end
#-------------------------------------------------------------------------------
    def make_idat
      header = "\x49\x44\x41\x54"
      data = make_bitmap_data
      data = Zlib::Deflate.deflate(data, 8)
      crc = [Zlib.crc32(header + data)].pack("N")
      size = [data.length].pack("N")
      return size + header + data + crc
    end
#-------------------------------------------------------------------------------
    def make_bitmap_data1
      data = []
      (0...@bitmap_Fx.height).each {|y|
        data.push(0)
        (0...@bitmap_Fx.width).each {|x|
          color = @bitmap_Fx.get_pixel(x, y)
          data.push(color.red)
          data.push(color.green)
          data.push(color.blue)
          data.push(color.alpha)
        }
      }
      return data.pack("C*")
    end
#-------------------------------------------------------------------------------
    def make_bitmap_data
      gz = Zlib::GzipWriter.open('hoge.gz')
      t_Fx = 0
      data = []
      (0...@bitmap_Fx.height).each {|y|
        data.push(0)
        (0...@bitmap_Fx.width).each {|x|
          t_Fx += 1
          Graphics.update if t_Fx % 10000 == 0
          if t_Fx % 100000 == 0
            s = data.pack("C*")
            gz.write(s)
            data.clear
          end
          color = @bitmap_Fx.get_pixel(x, y)
          data.push(color.red)
          data.push(color.green)
          data.push(color.blue)
          data.push(color.alpha)
        end
      end
      gz.write(data.pack("C*"))
      gz.close
      data.clear
      gz = Zlib::GzipReader.open('hoge.gz')
      data = gz.read
      gz.close
      File.delete('hoge.gz')
      return data
    end
#-------------------------------------------------------------------------------
    def make_iend
      return [0].pack("N") + 'IEND' + [Zlib.crc32('IEND')].pack("N")
    end
  end
end

#===============================================================================
# ** Bitmap
#===============================================================================

class Bitmap

  def make_png(name = 'bitmap', path = '', mode = 0)
    make_dir(path) if path != ''
    Zlib::PNG_Writer.open('temp.gz') {|gz| gz.make_png(self, mode) }
    Zlib::GzipReader.open('temp.gz') {|gz| $read = gz.read }
    f = File.open(path + name + '.png','wb')
    f.write($read)
    f.close
    File.delete('temp.gz')
  end
#-------------------------------------------------------------------------------
  def make_dir(path)
    dir = path.split("/")
    dir.each_index {|i|
      unless dir == "."
        add_dir = dir[0..i].join("/")
        begin
          Dir.mkdir(add_dir)
        rescue
        end
      end
    }
  end
end