mirror of
https://github.com/Barubary/dsdecmp.git
synced 2024-09-29 17:58:44 +02:00
741 lines
31 KiB
C#
741 lines
31 KiB
C#
using System;
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using System.Collections.Generic;
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using System.Text;
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using System.IO;
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using DSDecmp.Utils;
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namespace DSDecmp.Formats.Nitro
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{
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/// <summary>
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/// Compressor and decompressor for the Huffman format used in many of the games for the
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/// newer Nintendo consoles and handhelds.
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/// </summary>
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public class Huffman : NitroCFormat
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{
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public enum BlockSize : byte { FOURBIT = 0x24, EIGHTBIT = 0x28 }
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/// <summary>
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/// Sets the block size used when using the Huffman format to compress.
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/// </summary>
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public static BlockSize CompressBlockSize { get; set; }
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static Huffman()
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{
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CompressBlockSize = BlockSize.EIGHTBIT;
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}
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public Huffman() : base(0) { }
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public override bool Supports(System.IO.Stream stream, long inLength)
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{
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base.magicByte = (byte)BlockSize.FOURBIT;
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if (base.Supports(stream, inLength))
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return true;
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base.magicByte = (byte)BlockSize.EIGHTBIT;
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return base.Supports(stream, inLength);
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}
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#region Decompression method
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public override long Decompress(Stream instream, long inLength, Stream outstream)
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{
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#region GBATEK format specification
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/*
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Data Header (32bit)
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Bit0-3 Data size in bit units (normally 4 or 8)
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Bit4-7 Compressed type (must be 2 for Huffman)
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Bit8-31 24bit size of decompressed data in bytes
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Tree Size (8bit)
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Bit0-7 Size of Tree Table/2-1 (ie. Offset to Compressed Bitstream)
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Tree Table (list of 8bit nodes, starting with the root node)
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Root Node and Non-Data-Child Nodes are:
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Bit0-5 Offset to next child node,
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Next child node0 is at (CurrentAddr AND NOT 1)+Offset*2+2
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Next child node1 is at (CurrentAddr AND NOT 1)+Offset*2+2+1
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Bit6 Node1 End Flag (1=Next child node is data)
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Bit7 Node0 End Flag (1=Next child node is data)
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Data nodes are (when End Flag was set in parent node):
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Bit0-7 Data (upper bits should be zero if Data Size is less than 8)
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Compressed Bitstream (stored in units of 32bits)
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Bit0-31 Node Bits (Bit31=First Bit) (0=Node0, 1=Node1)
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*/
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#endregion
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long readBytes = 0;
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byte type = (byte)instream.ReadByte();
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BlockSize blockSize = BlockSize.FOURBIT;
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if (type != (byte)blockSize)
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blockSize = BlockSize.EIGHTBIT;
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if (type != (byte)blockSize)
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throw new InvalidDataException("The provided stream is not a valid Huffman "
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+ "compressed stream (invalid type 0x" + type.ToString("X") + "); unknown block size.");
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byte[] sizeBytes = new byte[3];
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instream.Read(sizeBytes, 0, 3);
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int decompressedSize = IOUtils.ToNDSu24(sizeBytes, 0);
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readBytes += 4;
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if (decompressedSize == 0)
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{
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sizeBytes = new byte[4];
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instream.Read(sizeBytes, 0, 4);
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decompressedSize = IOUtils.ToNDSs32(sizeBytes, 0);
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readBytes += 4;
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}
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#region Read the Huff-tree
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if (readBytes >= inLength)
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throw new NotEnoughDataException(0, decompressedSize);
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int treeSize = instream.ReadByte(); readBytes++;
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if (treeSize < 0)
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throw new InvalidDataException("The stream is too short to contain a Huffman tree.");
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treeSize = (treeSize + 1) * 2;
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if (readBytes + treeSize >= inLength)
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throw new InvalidDataException("The Huffman tree is too large for the given input stream.");
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long treeEnd = (instream.Position - 1) + treeSize;
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// the relative offset may be 4 more (when the initial decompressed size is 0), but
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// since it's relative that doesn't matter, especially when it only matters if
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// the given value is odd or even.
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HuffTreeNode rootNode = new HuffTreeNode(instream, false, 5, treeEnd);
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readBytes += treeSize;
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// re-position the stream after the tree (the stream is currently positioned after the root
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// node, which is located at the start of the tree definition)
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instream.Position = treeEnd;
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#endregion
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// the current u32 we are reading bits from.
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uint data = 0;
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// the amount of bits left to read from <data>
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byte bitsLeft = 0;
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// a cache used for writing when the block size is four bits
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int cachedByte = -1;
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// the current output size
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int currentSize = 0;
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HuffTreeNode currentNode = rootNode;
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byte[] buffer = new byte[4];
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while (currentSize < decompressedSize)
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{
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#region find the next reference to a data node
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while (!currentNode.IsData)
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{
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// if there are no bits left to read in the data, get a new byte from the input
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if (bitsLeft == 0)
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{
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if (readBytes >= inLength)
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throw new NotEnoughDataException(currentSize, decompressedSize);
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int nRead = instream.Read(buffer, 0, 4);
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if (nRead < 4)
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throw new StreamTooShortException();
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readBytes += nRead;
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data = IOUtils.ToNDSu32(buffer, 0);
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bitsLeft = 32;
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}
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// get the next bit
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bitsLeft--;
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bool nextIsOne = (data & (1 << bitsLeft)) != 0;
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// go to the next node, the direction of the child depending on the value of the current/next bit
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currentNode = nextIsOne ? currentNode.Child1 : currentNode.Child0;
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}
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#endregion
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#region write the data in the current node (when possible)
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switch (blockSize)
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{
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case BlockSize.EIGHTBIT:
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{
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// just copy the data if the block size is a full byte
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outstream.WriteByte(currentNode.Data);
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currentSize++;
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break;
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}
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case BlockSize.FOURBIT:
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{
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// cache the first half of the data if the block size is a half byte
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if (cachedByte < 0)
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{
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cachedByte = currentNode.Data << 4;
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}
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else
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{
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// if we already cached a half-byte, combine the two halves and write the full byte.
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cachedByte |= currentNode.Data;
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outstream.WriteByte((byte)cachedByte);
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currentSize++;
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// be sure to forget the two written half-bytes
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cachedByte = -1;
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}
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break;
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}
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default:
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throw new Exception("Unknown block size " + blockSize.ToString());
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}
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#endregion
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outstream.Flush();
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// make sure to start over next round
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currentNode = rootNode;
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}
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// the data is 4-byte aligned. Although very unlikely in this case (compressed bit blocks
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// are always 4 bytes long, and the tree size is generally 4-byte aligned as well),
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// skip any padding due to alignment.
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if (readBytes % 4 != 0)
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readBytes += 4 - (readBytes % 4);
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if (readBytes < inLength)
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{
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throw new TooMuchInputException(readBytes, inLength);
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}
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return decompressedSize;
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}
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#endregion
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public override int Compress(Stream instream, long inLength, Stream outstream)
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{
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switch (CompressBlockSize)
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{
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case BlockSize.FOURBIT:
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return Compress4(instream, inLength, outstream);
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case BlockSize.EIGHTBIT:
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return Compress8(instream, inLength, outstream);
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default:
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throw new Exception("Unhandled BlockSize " + CompressBlockSize);
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}
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}
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#region 4-bit block size Compression method
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/// <summary>
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/// Applies Huffman compression with a datablock size of 4 bits.
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/// </summary>
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/// <param name="instream">The stream to compress.</param>
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/// <param name="inLength">The length of the input stream.</param>
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/// <param name="outstream">The stream to write the decompressed data to.</param>
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/// <returns>The size of the decompressed data.</returns>
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private int Compress4(Stream instream, long inLength, Stream outstream)
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{
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if (inLength > 0xFFFFFF)
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throw new InputTooLargeException();
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// cache the input, as we need to build a frequency table
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byte[] inputData = new byte[inLength];
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instream.Read(inputData, 0, (int)inLength);
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// build that frequency table.
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int[] frequencies = new int[0x10];
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for (int i = 0; i < inLength; i++)
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{
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frequencies[inputData[i] & 0xF]++;
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frequencies[(inputData[i] >> 4) & 0xF]++;
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}
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#region Build the Huffman tree
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SimpleReversedPrioQueue<int, HuffTreeNode> leafQueue = new SimpleReversedPrioQueue<int, HuffTreeNode>();
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SimpleReversedPrioQueue<int, HuffTreeNode> nodeQueue = new SimpleReversedPrioQueue<int, HuffTreeNode>();
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int nodeCount = 0;
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// make all leaf nodes, and put them in the leaf queue. Also save them for later use.
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HuffTreeNode[] leaves = new HuffTreeNode[0x10];
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for (int i = 0; i < 0x10; i++)
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{
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// there is no need to store leaves that are not used
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if (frequencies[i] == 0)
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continue;
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HuffTreeNode node = new HuffTreeNode((byte)i, true, null, null);
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leaves[i] = node;
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leafQueue.Enqueue(frequencies[i], node);
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nodeCount++;
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}
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while (leafQueue.Count + nodeQueue.Count > 1)
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{
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// get the two nodes with the lowest priority.
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HuffTreeNode one = null, two = null;
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int onePrio, twoPrio;
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one = GetLowest(leafQueue, nodeQueue, out onePrio);
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two = GetLowest(leafQueue, nodeQueue, out twoPrio);
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// give those two a common parent, and put that node in the node queue
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HuffTreeNode newNode = new HuffTreeNode(0, false, one, two);
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nodeQueue.Enqueue(onePrio + twoPrio, newNode);
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nodeCount++;
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}
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int rootPrio;
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HuffTreeNode root = nodeQueue.Dequeue(out rootPrio);
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// set the depth of all nodes in the tree, such that we know for each leaf how long
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// its codeword is.
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root.Depth = 0;
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#endregion
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// now that we have a tree, we can write that tree and follow with the data.
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// write the compression header first
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outstream.WriteByte((byte)BlockSize.FOURBIT); // this is block size 4 only
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outstream.WriteByte((byte)(inLength & 0xFF));
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outstream.WriteByte((byte)((inLength >> 8) & 0xFF));
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outstream.WriteByte((byte)((inLength >> 16) & 0xFF));
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int compressedLength = 4;
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#region write the tree
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outstream.WriteByte((byte)((nodeCount - 1) / 2));
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compressedLength++;
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// use a breadth-first traversal to store the tree, such that we do not need to store/calculate the side of each sub-tree.
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LinkedList<HuffTreeNode> printQueue = new LinkedList<HuffTreeNode>();
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printQueue.AddLast(root);
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while (printQueue.Count > 0)
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{
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HuffTreeNode node = printQueue.First.Value;
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printQueue.RemoveFirst();
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if (node.IsData)
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{
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outstream.WriteByte(node.Data);
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}
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else
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{
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// bits 0-5: 'offset' = # nodes in queue left
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// bit 6: node1 end flag
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// bit 7: node0 end flag
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byte data = (byte)(printQueue.Count / 2);
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data = (byte)(data & 0x3F);
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if (node.Child0.IsData)
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data |= 0x80;
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if (node.Child1.IsData)
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data |= 0x40;
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outstream.WriteByte(data);
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printQueue.AddLast(node.Child0);
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printQueue.AddLast(node.Child1);
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}
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compressedLength++;
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}
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#endregion
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#region write the data
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// the codewords are stored in blocks of 32 bits
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uint datablock = 0;
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byte bitsLeftToWrite = 32;
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for (int i = 0; i < inLength; i++)
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{
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byte data = inputData[i];
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for (int j = 0; j < 2; j++)
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{
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HuffTreeNode node = leaves[(data >> (4 - j * 4)) & 0xF];
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// the depth of the node is the length of the codeword required to encode the byte
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int depth = node.Depth;
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bool[] path = new bool[depth];
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for (int d = 0; d < depth; d++)
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{
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path[depth - d - 1] = node.IsChild1;
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node = node.Parent;
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}
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for (int d = 0; d < depth; d++)
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{
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if (bitsLeftToWrite == 0)
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{
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outstream.Write(IOUtils.FromNDSu32(datablock), 0, 4);
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compressedLength += 4;
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datablock = 0;
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bitsLeftToWrite = 32;
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}
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bitsLeftToWrite--;
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if (path[d])
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datablock |= (uint)(1 << bitsLeftToWrite);
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// no need to OR the buffer with 0 if it is child0
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}
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}
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}
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// write the partly filled data block as well
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if (bitsLeftToWrite != 32)
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{
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outstream.Write(IOUtils.FromNDSu32(datablock), 0, 4);
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compressedLength += 4;
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}
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#endregion
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return compressedLength;
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}
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#endregion
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#region 8-bit block size Compression method
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/// <summary>
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/// Applies Huffman compression with a datablock size of 8 bits.
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/// </summary>
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/// <param name="instream">The stream to compress.</param>
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/// <param name="inLength">The length of the input stream.</param>
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/// <param name="outstream">The stream to write the decompressed data to.</param>
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/// <returns>The size of the decompressed data.</returns>
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private int Compress8(Stream instream, long inLength, Stream outstream)
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{
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if (inLength > 0xFFFFFF)
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throw new InputTooLargeException();
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// cache the input, as we need to build a frequency table
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byte[] inputData = new byte[inLength];
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instream.Read(inputData, 0, (int)inLength);
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// build that frequency table.
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int[] frequencies = new int[0x100];
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for (int i = 0; i < inLength; i++)
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frequencies[inputData[i]]++;
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#region Build the Huffman tree
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SimpleReversedPrioQueue<int, HuffTreeNode> leafQueue = new SimpleReversedPrioQueue<int, HuffTreeNode>();
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SimpleReversedPrioQueue<int, HuffTreeNode> nodeQueue = new SimpleReversedPrioQueue<int, HuffTreeNode>();
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int nodeCount = 0;
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// make all leaf nodes, and put them in the leaf queue. Also save them for later use.
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HuffTreeNode[] leaves = new HuffTreeNode[0x100];
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for (int i = 0; i < 0x100; i++)
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{
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// there is no need to store leaves that are not used
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if (frequencies[i] == 0)
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continue;
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HuffTreeNode node = new HuffTreeNode((byte)i, true, null, null);
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leaves[i] = node;
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leafQueue.Enqueue(frequencies[i], node);
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nodeCount++;
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}
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while (leafQueue.Count + nodeQueue.Count > 1)
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{
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// get the two nodes with the lowest priority.
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HuffTreeNode one = null, two = null;
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int onePrio, twoPrio;
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one = GetLowest(leafQueue, nodeQueue, out onePrio);
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two = GetLowest(leafQueue, nodeQueue, out twoPrio);
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// give those two a common parent, and put that node in the node queue
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HuffTreeNode newNode = new HuffTreeNode(0, false, one, two);
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nodeQueue.Enqueue(onePrio + twoPrio, newNode);
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nodeCount++;
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}
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int rootPrio;
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HuffTreeNode root = nodeQueue.Dequeue(out rootPrio);
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// set the depth of all nodes in the tree, such that we know for each leaf how long
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// its codeword is.
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root.Depth = 0;
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#endregion
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// now that we have a tree, we can write that tree and follow with the data.
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// write the compression header first
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outstream.WriteByte((byte)BlockSize.EIGHTBIT); // this is block size 8 only
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outstream.WriteByte((byte)(inLength & 0xFF));
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outstream.WriteByte((byte)((inLength >> 8) & 0xFF));
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outstream.WriteByte((byte)((inLength >> 16) & 0xFF));
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int compressedLength = 4;
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#region write the tree
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outstream.WriteByte((byte)((nodeCount - 1) / 2));
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compressedLength++;
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// use a breadth-first traversal to store the tree, such that we do not need to store/calculate the side of each sub-tree.
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LinkedList<HuffTreeNode> printQueue = new LinkedList<HuffTreeNode>();
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printQueue.AddLast(root);
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while (printQueue.Count > 0)
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{
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HuffTreeNode node = printQueue.First.Value;
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printQueue.RemoveFirst();
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if (node.IsData)
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{
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outstream.WriteByte(node.Data);
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}
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else
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{
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// bits 0-5: 'offset' = # nodes in queue left
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// bit 6: node1 end flag
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// bit 7: node0 end flag
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byte data = (byte)(printQueue.Count / 2);
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data = (byte)(data & 0x3F);
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if (node.Child0.IsData)
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data |= 0x80;
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if (node.Child1.IsData)
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data |= 0x40;
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outstream.WriteByte(data);
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printQueue.AddLast(node.Child0);
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printQueue.AddLast(node.Child1);
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}
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compressedLength++;
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}
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#endregion
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#region write the data
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// the codewords are stored in blocks of 32 bits
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uint datablock = 0;
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byte bitsLeftToWrite = 32;
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for (int i = 0; i < inLength; i++)
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{
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byte data = inputData[i];
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HuffTreeNode node = leaves[data];
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// the depth of the node is the length of the codeword required to encode the byte
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int depth = node.Depth;
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bool[] path = new bool[depth];
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for (int d = 0; d < depth; d++)
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{
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path[depth - d - 1] = node.IsChild1;
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node = node.Parent;
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}
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for (int d = 0; d < depth; d++)
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{
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if (bitsLeftToWrite == 0)
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{
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outstream.Write(IOUtils.FromNDSu32(datablock), 0, 4);
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compressedLength += 4;
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datablock = 0;
|
|
bitsLeftToWrite = 32;
|
|
}
|
|
bitsLeftToWrite--;
|
|
if (path[d])
|
|
datablock |= (uint)(1 << bitsLeftToWrite);
|
|
// no need to OR the buffer with 0 if it is child0
|
|
}
|
|
}
|
|
|
|
// write the partly filled data block as well
|
|
if (bitsLeftToWrite != 32)
|
|
{
|
|
outstream.Write(IOUtils.FromNDSu32(datablock), 0, 4);
|
|
compressedLength += 4;
|
|
}
|
|
|
|
#endregion
|
|
|
|
return compressedLength;
|
|
}
|
|
#endregion
|
|
|
|
/// <summary>
|
|
/// Gets the tree node with the lowest priority (frequency) from the leaf and node queues.
|
|
/// If the priority is the same for both head items in the queues, the node from the leaf queue is picked.
|
|
/// </summary>
|
|
private HuffTreeNode GetLowest(SimpleReversedPrioQueue<int, HuffTreeNode> leafQueue, SimpleReversedPrioQueue<int, HuffTreeNode> nodeQueue, out int prio)
|
|
{
|
|
if (leafQueue.Count == 0)
|
|
return nodeQueue.Dequeue(out prio);
|
|
else if (nodeQueue.Count == 0)
|
|
return leafQueue.Dequeue(out prio);
|
|
else
|
|
{
|
|
int leafPrio, nodePrio;
|
|
leafQueue.Peek(out leafPrio);
|
|
nodeQueue.Peek(out nodePrio);
|
|
// pick a node from the leaf queue when the priorities are equal.
|
|
if (leafPrio <= nodePrio)
|
|
return leafQueue.Dequeue(out prio);
|
|
else
|
|
return nodeQueue.Dequeue(out prio);
|
|
}
|
|
}
|
|
|
|
#region Utility class: HuffTreeNode
|
|
/// <summary>
|
|
/// A single node in a Huffman tree.
|
|
/// </summary>
|
|
public class HuffTreeNode
|
|
{
|
|
/// <summary>
|
|
/// The data contained in this node. May not mean anything when <code>isData == false</code>
|
|
/// </summary>
|
|
private byte data;
|
|
/// <summary>
|
|
/// A flag indicating if this node has been filled.
|
|
/// </summary>
|
|
private bool isFilled;
|
|
/// <summary>
|
|
/// The data contained in this node. May not mean anything when <code>isData == false</code>.
|
|
/// Throws a NullReferenceException when this node has not been defined (ie: reference was outside the
|
|
/// bounds of the tree definition)
|
|
/// </summary>
|
|
public byte Data
|
|
{
|
|
get
|
|
{
|
|
if (!this.isFilled) throw new NullReferenceException("Reference to an undefined node in the huffman tree.");
|
|
return this.data;
|
|
}
|
|
}
|
|
/// <summary>
|
|
/// A flag indicating if this node contains data. If not, this is not a leaf node.
|
|
/// </summary>
|
|
private bool isData;
|
|
/// <summary>
|
|
/// Returns true if this node represents data.
|
|
/// </summary>
|
|
public bool IsData { get { return this.isData; } }
|
|
|
|
/// <summary>
|
|
/// The child of this node at side 0
|
|
/// </summary>
|
|
private HuffTreeNode child0;
|
|
/// <summary>
|
|
/// The child of this node at side 0
|
|
/// </summary>
|
|
public HuffTreeNode Child0 { get { return this.child0; } }
|
|
/// <summary>
|
|
/// The child of this node at side 1
|
|
/// </summary>
|
|
private HuffTreeNode child1;
|
|
/// <summary>
|
|
/// The child of this node at side 1
|
|
/// </summary>
|
|
public HuffTreeNode Child1 { get { return this.child1; } }
|
|
/// <summary>
|
|
/// The parent node of this node.
|
|
/// </summary>
|
|
public HuffTreeNode Parent { get; private set; }
|
|
/// <summary>
|
|
/// Determines if this is the Child0 of the parent node. Assumes there is a parent.
|
|
/// </summary>
|
|
public bool IsChild0 { get { return this.Parent.child0 == this; } }
|
|
/// <summary>
|
|
/// Determines if this is the Child1 of the parent node. Assumes there is a parent.
|
|
/// </summary>
|
|
public bool IsChild1 { get { return this.Parent.child1 == this; } }
|
|
|
|
private int depth;
|
|
/// <summary>
|
|
/// Get or set the depth of this node. Will not be set automatically, but
|
|
/// will be set recursively (the depth of all child nodes will be updated when this is set).
|
|
/// </summary>
|
|
public int Depth
|
|
{
|
|
get { return this.depth; }
|
|
set
|
|
{
|
|
this.depth = value;
|
|
// recursively set the depth of the child nodes.
|
|
if (!this.isData)
|
|
{
|
|
this.child0.Depth = this.depth + 1;
|
|
this.child1.Depth = this.depth + 1;
|
|
}
|
|
}
|
|
}
|
|
|
|
/// <summary>
|
|
/// Manually creates a new node for a huffman tree.
|
|
/// </summary>
|
|
/// <param name="data">The data for this node.</param>
|
|
/// <param name="isData">If this node represents data.</param>
|
|
/// <param name="child0">The child of this node on the 0 side.</param>
|
|
/// <param name="child1">The child of this node on the 1 side.</param>
|
|
public HuffTreeNode(byte data, bool isData, HuffTreeNode child0, HuffTreeNode child1)
|
|
{
|
|
this.data = data;
|
|
this.isData = isData;
|
|
this.child0 = child0;
|
|
this.child1 = child1;
|
|
this.isFilled = true;
|
|
if (!isData)
|
|
{
|
|
this.child0.Parent = this;
|
|
this.child1.Parent = this;
|
|
}
|
|
}
|
|
|
|
/// <summary>
|
|
/// Creates a new node in the Huffman tree.
|
|
/// </summary>
|
|
/// <param name="stream">The stream to read from. It is assumed that there is (at least)
|
|
/// one more byte available to read.</param>
|
|
/// <param name="isData">If this node is a data-node.</param>
|
|
/// <param name="relOffset">The offset of this node in the source data, relative to the start
|
|
/// of the compressed file.</param>
|
|
/// <param name="maxStreamPos">The indicated end of the huffman tree. If the stream is past
|
|
/// this position, the tree is invalid.</param>
|
|
public HuffTreeNode(Stream stream, bool isData, long relOffset, long maxStreamPos)
|
|
{
|
|
/*
|
|
Tree Table (list of 8bit nodes, starting with the root node)
|
|
Root Node and Non-Data-Child Nodes are:
|
|
Bit0-5 Offset to next child node,
|
|
Next child node0 is at (CurrentAddr AND NOT 1)+Offset*2+2
|
|
Next child node1 is at (CurrentAddr AND NOT 1)+Offset*2+2+1
|
|
Bit6 Node1 End Flag (1=Next child node is data)
|
|
Bit7 Node0 End Flag (1=Next child node is data)
|
|
Data nodes are (when End Flag was set in parent node):
|
|
Bit0-7 Data (upper bits should be zero if Data Size is less than 8)
|
|
*/
|
|
|
|
if (stream.Position >= maxStreamPos)
|
|
{
|
|
// this happens when part of the tree is unused.
|
|
this.isFilled = false;
|
|
return;
|
|
}
|
|
this.isFilled = true;
|
|
int readData = stream.ReadByte();
|
|
if (readData < 0)
|
|
throw new StreamTooShortException();
|
|
this.data = (byte)readData;
|
|
|
|
this.isData = isData;
|
|
|
|
if (!this.isData)
|
|
{
|
|
int offset = this.data & 0x3F;
|
|
bool zeroIsData = (this.data & 0x80) > 0;
|
|
bool oneIsData = (this.data & 0x40) > 0;
|
|
|
|
// off AND NOT 1 == off XOR (off AND 1)
|
|
long zeroRelOffset = (relOffset ^ (relOffset & 1)) + offset * 2 + 2;
|
|
|
|
long currStreamPos = stream.Position;
|
|
// position the stream right before the 0-node
|
|
stream.Position += (zeroRelOffset - relOffset) - 1;
|
|
// read the 0-node
|
|
this.child0 = new HuffTreeNode(stream, zeroIsData, zeroRelOffset, maxStreamPos);
|
|
this.child0.Parent = this;
|
|
// the 1-node is directly behind the 0-node
|
|
this.child1 = new HuffTreeNode(stream, oneIsData, zeroRelOffset + 1, maxStreamPos);
|
|
this.child1.Parent = this;
|
|
|
|
// reset the stream position to right behind this node's data
|
|
stream.Position = currStreamPos;
|
|
}
|
|
}
|
|
|
|
public override string ToString()
|
|
{
|
|
if (this.isData)
|
|
{
|
|
return "<" + this.data.ToString("X2") + ">";
|
|
}
|
|
else
|
|
{
|
|
return "[" + this.child0.ToString() + "," + this.child1.ToString() + "]";
|
|
}
|
|
}
|
|
|
|
}
|
|
#endregion
|
|
}
|
|
}
|