conco/OpenMaidEngine
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases 3 Wiki Activity

Decode AGF textures through the asset store

Browse Source
This commit is contained in:
gamer147
2026-07-11 09:55:58 -04:00
parent b6c3b1660d
commit a1f6d0ab51
15 changed files with 468 additions and 158 deletions
Download Patch File Download Diff File Expand all files Collapse all files

41
engine/Age.Engine/Sys4/Sys4AssetCatalog.cs
View File

@@ -55,8 +55,8 @@ public sealed class Sys4AssetCatalog
if (expandedSize == 0 || expandedSize > int.MaxValue)
throw new InvalidDataException($"{name}: invalid expanded size {expandedSize}");
var blob = DecompressLzss(data.AsSpan(PackedSizeOffset + 4, checked((int)packedSize)),
checked((int)expandedSize), name);
var blob = LzssDecoder.Decode(data.AsSpan(PackedSizeOffset + 4, checked((int)packedSize)),
checked((int)expandedSize), name);
int p = 0;
uint ReadU32()
{
@@ -145,41 +145,4 @@ public sealed class Sys4AssetCatalog
return Encoding.GetEncoding(932).GetString(bytes);
}
private static byte[] DecompressLzss(ReadOnlySpan<byte> source, int expectedSize, string name)
{
var frame = new byte[0x1000];
int framePos = 0xfee, input = 0, output = 0;
var result = new byte[expectedSize];
while (output < expectedSize)
{
if (input >= source.Length) throw new InvalidDataException($"{name}: LZSS stream ended early");
int control = source[input++];
for (int bit = 1; bit <= 0x80 && output < expectedSize; bit <<= 1)
{
if ((control & bit) != 0)
{
if (input >= source.Length) throw new InvalidDataException($"{name}: truncated LZSS literal");
byte value = source[input++];
result[output++] = value;
frame[framePos] = value;
framePos = (framePos + 1) & 0xfff;
}
else
{
if (input > source.Length - 2) throw new InvalidDataException($"{name}: truncated LZSS back-reference");
int lo = source[input++], hi = source[input++];
int readPos = ((hi & 0xf0) << 4) | lo;
int length = 3 + (hi & 0x0f);
for (int j = 0; j < length && output < expectedSize; j++)
{
byte value = frame[readPos++ & 0xfff];
result[output++] = value;
frame[framePos] = value;
framePos = (framePos + 1) & 0xfff;
}
}
}
}
return result;
}
}