BrawlLib.Wii.Compression.LZ77 Class Reference

Inheritance diagram for BrawlLib.Wii.Compression.LZ77:

Public Member Functions
void	Dispose ()
int	Compress (VoidPtr srcAddr, int srcLen, Stream outStream, IProgressTracker progress, bool extFmt)

Static Public Member Functions
static int	Compact (VoidPtr srcAddr, int srcLen, Stream outStream, ResourceNode r, bool extendedFormat)
static void	Expand (CompressionHeader *header, VoidPtr dstAddress, int dstLen)
static void	Expand (VoidPtr data, VoidPtr dstAddress, int dstLen, bool extFmt)

Public Attributes
int	PatternLength = 18

Static Public Attributes
const int	WindowMask = 0xFFF
const int	WindowLength = 4096
const int	MinMatch = 3

Member Function Documentation

Compact()

static int BrawlLib.Wii.Compression.LZ77.Compact ( VoidPtr  srcAddr, int  srcLen, Stream  outStream, ResourceNode  r, bool  extendedFormat  )

inlinestatic

        {
            using (LZ77 lz = new LZ77())
            {
                using (ProgressWindow prog = new ProgressWindow(r.RootNode._mainForm,
                    (extendedFormat ? "Extended " : "") + "LZ77",
                    $"Compressing {r.Name}, please wait...", false))
                {
                    return lz.Compress(srcAddr, srcLen, outStream, prog, extendedFormat);
                }
            }
        }

Compress()

int BrawlLib.Wii.Compression.LZ77.Compress ( VoidPtr  srcAddr, int  srcLen, Stream  outStream, IProgressTracker  progress, bool  extFmt  )

inline

        {
            int dstLen = 4, bitCount;
            byte control;
 
            byte* sPtr = (byte*) srcAddr;
            int matchLength, matchOffset = 0;
            PatternLength = extFmt ? 0xFFFF + 0xFF + 0xF + 3 : 0xF + 3;
 
            //Initialize
            Memory.Fill(_First, 0x40000, 0xFF);
            _wIndex = _wLength = 0;
 
            //Write header
            CompressionHeader header = new CompressionHeader
            {
                Algorithm = CompressionType.LZ77,
                ExpandedSize = (uint) srcLen,
                IsExtendedLZ77 = extFmt
            };
            outStream.Write(&header, 4 + (header.LargeSize ? 4 : 0));
 
            List<byte> blockBuffer;
            int lastUpdate = srcLen;
            int remaining = srcLen;
 
            progress?.Begin(0, remaining, 0);
 
            while (remaining > 0)
            {
                blockBuffer = new List<byte> {0};
                for (bitCount = 0, control = 0; bitCount < 8 && remaining > 0; bitCount++)
                {
                    control <<= 1;
                    if ((matchLength = FindPattern(sPtr, remaining, ref matchOffset)) != 0)
                    {
                        int length;
                        if (extFmt)
                        {
                            if (matchLength >= 0xFF + 0xF + 3)
                            {
                                length = matchLength - 0xFF - 0xF - 3;
                                blockBuffer.Add((byte) (0x10 | (length >> 12)));
                                blockBuffer.Add((byte) (length >> 4));
                            }
                            else if (matchLength >= 0xF + 2)
                            {
                                length = matchLength - 0xF - 2;
                                blockBuffer.Add((byte) (length >> 4));
                            }
                            else
                            {
                                length = matchLength - 1;
                            }
                        }
                        else
                        {
                            length = matchLength - 3;
                        }
 
                        control |= 1;
                        blockBuffer.Add((byte) ((length << 4) | ((matchOffset - 1) >> 8)));
                        blockBuffer.Add((byte) (matchOffset - 1));
                    }
                    else
                    {
                        matchLength = 1;
                        blockBuffer.Add(*sPtr);
                    }
 
                    Consume(sPtr, matchLength, remaining);
                    sPtr += matchLength;
                    remaining -= matchLength;
                }
 
                //Left-align bits
                control <<= 8 - bitCount;
 
                //Write buffer
                blockBuffer[0] = control;
                outStream.Write(blockBuffer.ToArray(), 0, blockBuffer.Count);
                dstLen += blockBuffer.Count;
 
                if (progress != null)
                {
                    if (lastUpdate - remaining > 0x4000)
                    {
                        lastUpdate = remaining;
                        progress.Update(srcLen - remaining);
                    }
                }
            }
 
            outStream.Flush();
 
            progress?.Finish();
 
            return dstLen;
        }

Dispose()

void BrawlLib.Wii.Compression.LZ77.Dispose ( )

inline

        {
            if (_dataAddr)
            {
                Marshal.FreeHGlobal(_dataAddr);
                _dataAddr = 0;
            }
 
            GC.SuppressFinalize(this);
        }

Expand() [1/2]

static void BrawlLib.Wii.Compression.LZ77.Expand ( CompressionHeader *  header, VoidPtr  dstAddress, int  dstLen  )

inlinestatic

        {
            Expand(header->Data, dstAddress, dstLen, header->IsExtendedLZ77);
        }

Expand() [2/2]

static void BrawlLib.Wii.Compression.LZ77.Expand ( VoidPtr  data, VoidPtr  dstAddress, int  dstLen, bool  extFmt  )

inlinestatic

        {
            for (byte* srcPtr = (byte*) data, dstPtr = (byte*) dstAddress, ceiling = dstPtr + dstLen; dstPtr < ceiling;)
            {
                for (byte control = *srcPtr++, bit = 8; bit-- != 0 && dstPtr != ceiling;)
                {
                    if ((control & (1 << bit)) == 0)
                    {
                        *dstPtr++ = *srcPtr++;
                    }
                    else
                    {
                        int temp = *srcPtr >> 4,
                            num = !extFmt
                                ? temp + 3
                                : temp == 1
                                    ? (((*srcPtr++ & 0x0F) << 12) | (*srcPtr++ << 4) | (*srcPtr >> 4)) + 0xFF + 0xF + 3
                                    : temp == 0
                                        ? (((*srcPtr++ & 0x0F) << 4) | (*srcPtr >> 4)) + 0xF + 2
                                        : temp + 1,
                            offset = (((*srcPtr++ & 0xF) << 8) | *srcPtr++) + 2;
                        while (dstPtr != ceiling && num-- > 0)
                        {
                            *dstPtr++ = dstPtr[-offset];
                        }
                    }
                }
            }
        }

Member Data Documentation

MinMatch

const int BrawlLib.Wii.Compression.LZ77.MinMatch = 3

static

PatternLength

int BrawlLib.Wii.Compression.LZ77.PatternLength = 18

WindowLength

const int BrawlLib.Wii.Compression.LZ77.WindowLength = 4096

static

WindowMask

const int BrawlLib.Wii.Compression.LZ77.WindowMask = 0xFFF

static

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The documentation for this class was generated from the following file:

• BrawlLib/Wii/Compression/LZ77.cs