Abolished screen border, screenshots are now png format, removed Sprite Resizer scripts, credited mkxp-z

Data/Scripts/001_Technical/002_Ruby Utilities.rb

@@ -165,6 +165,106 @@ module Enumerable
   end
 end
 
+#===============================================================================
+# class ByteWriter (used by def save_to_png below)
+#===============================================================================
+class ByteWriter
+  def initialize(filename)
+    @file = File.new(filename, "wb")
+  end
+
+  def <<(*data)
+    write(*data)
+  end
+
+  def write(*data)
+    data.each do |e|
+      if e.is_a?(Array)
+        e.each { |item| write(item) }
+      elsif e.is_a?(Numeric)
+        @file.putc e
+      else
+        raise "Invalid data for writing."
+      end
+    end
+  end
+
+  def write_int(int)
+    self << ByteWriter.to_bytes(int)
+  end
+
+  def close
+    @file.close
+    @file = nil
+  end
+
+  def self.to_bytes(int)
+    return [
+      (int >> 24) & 0xFF,
+      (int >> 16) & 0xFF,
+      (int >> 8) & 0xFF,
+       int & 0xFF
+    ]
+  end
+end
+
+#===============================================================================
+# class Bitmap
+#===============================================================================
+class Bitmap
+  def save_to_png(filename)
+    f = ByteWriter.new(filename)
+    #============================= Writing header =============================#
+    # PNG signature
+    f << [0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A]
+    # Header length
+    f << [0x00, 0x00, 0x00, 0x0D]
+    # IHDR
+    headertype = [0x49, 0x48, 0x44, 0x52]
+    f << headertype
+    # Width, height, compression, filter, interlacing
+    headerdata = ByteWriter.to_bytes(self.width).
+      concat(ByteWriter.to_bytes(self.height)).
+      concat([0x08, 0x06, 0x00, 0x00, 0x00])
+    f << headerdata
+    # CRC32 checksum
+    sum = headertype.concat(headerdata)
+    f.write_int Zlib::crc32(sum.pack("C*"))
+    #============================== Writing data ==============================#
+    data = []
+    for y in 0...self.height
+      # Start scanline
+      data << 0x00   # Filter: None
+      for x in 0...self.width
+        px = self.get_pixel(x, y)
+        # Write raw RGBA pixels
+        data << px.red
+        data << px.green
+        data << px.blue
+        data << px.alpha
+      end
+    end
+    # Zlib deflation
+    smoldata = Zlib::Deflate.deflate(data.pack("C*")).bytes.map
+    # data chunk length
+    f.write_int smoldata.size
+    # IDAT
+    f << [0x49, 0x44, 0x41, 0x54]
+    f << smoldata
+    # CRC32 checksum
+    f.write_int Zlib::crc32([0x49, 0x44, 0x41, 0x54].concat(smoldata).pack("C*"))
+    #============================== End Of File ===============================#
+    # Empty chunk
+    f << [0x00, 0x00, 0x00, 0x00]
+    # IEND
+    f << [0x49, 0x45, 0x4E, 0x44]
+    # CRC32 checksum
+    f.write_int Zlib::crc32([0x49, 0x45, 0x4E, 0x44].pack("C*"))
+    f.close
+    return nil
+  end
+end
+
 #===============================================================================
 # Kernel methods
 #===============================================================================