private int SegmentLength(ChunkIterator iterator, int direction, int start)
{
var result = start;
var owner = iterator.Here();
for (var i = 0; i < SymbolsNeeded - start; ++i)
{
var symbol = direction switch
{
0 => iterator.Up(),
1 => iterator.UpRight(),
2 => iterator.Right(),
3 => iterator.DownRight(),
4 => iterator.Down(),
5 => iterator.DownLeft(),
6 => iterator.Left(),
7 => iterator.UpLeft(),
_ => throw new ArgumentOutOfRangeException("internal error: direction does not exist")
};
if (iterator.Here() != owner || ++result >= SymbolsNeeded)
{
break;
}
}
iterator.Reset();
return(result);
}
}
private bool CheckDirection(ChunkIterator iterator, int direction)
{
var length = SegmentLength(iterator, direction, 1);
if (length < SymbolsNeeded)
{
var opposite = (direction + 4) % 8;
length = SegmentLength(iterator, opposite, length);
}
return(length >= SymbolsNeeded);
}
Room ReadRoomCore(long offset, long chunkSize)
{
var objImages = new Dictionary<ushort, byte[]>();
var room = new Room { Size = (int)chunkSize };
var it = new ChunkIterator(_reader, chunkSize);
while (it.MoveNext())
{
switch (it.Current.Tag)
{
case "HD":
// Room Header
room.Header = ReadRMHD();
break;
case "CC":
// Color Cylcle
room.ColorCycle = ReadCYCL();
break;
case "SP":
// EPAL
ReadEPAL();
break;
case "BX":
// BOXD
{
var size = (int)(it.Current.Size - 6);
var numBoxes = _reader.ReadByte();
var pos = _reader.BaseStream.Position;
for (var i = 0; i < numBoxes; i++)
{
var box = ReadBox();
room.Boxes.Add(box);
}
size -= (int)(_reader.BaseStream.Position - pos);
if (size > 0)
{
room.BoxMatrix.Clear();
room.BoxMatrix.AddRange(_reader.ReadBytes(size));
}
}
break;
case "PA":
{
// Palette
var colors = ReadCLUT();
room.HasPalette = true;
Array.Copy(colors, room.Palette.Colors, colors.Length);
}
break;
case "SA":
// Scale
if (it.Current.Size > 6)
{
room.Scales = ReadSCAL();
}
break;
case "BM":
// Bitmap
if (it.Current.Size > 6)
{
using (var ms = new MemoryStream(_reader.ReadBytes((int)(it.Current.Size - 6))))
{
room.Image = ReadImage(ms, room.Header.Width / 8);
}
}
break;
case "EN":
{
// Entry script
room.EntryScript.Data = _reader.ReadBytes((int)(it.Current.Size - 6));
}
break;
case "EX":
{
// Exit script
room.ExitScript.Data = _reader.ReadBytes((int)(it.Current.Size - 6));
}
break;
case "LC": //LC
{
// *NLSC* number of local scripts
var num = _reader.ReadUInt16();
}
break;
case "LS":
{
// local scripts
var index = _reader.ReadByte();
var pos = _reader.BaseStream.Position;
room.LocalScripts[index - 0xC8] = new ScriptData
{
Offset = pos - offset - 8,
Data = _reader.ReadBytes((int)(it.Current.Size - 7))
};
}
break;
case "OI":
{
// Object Image
var objId = _reader.ReadUInt16();
if (it.Current.Size > 8)
{
var img = _reader.ReadBytes((int)(it.Current.Size - 6));
objImages.Add(objId, img);
}
}
break;
case "OC":
{
// Object script
var objId = _reader.ReadUInt16();
var t = _reader.ReadByte();
System.Diagnostics.Debug.WriteLine("objId={0}: {1}", objId, t);
var x = _reader.ReadByte();
var tmp = _reader.ReadByte();
var y = tmp & 0x7F;
byte parentState = (byte)(((tmp & 0x80) != 0) ? 1 : 0);
var width = _reader.ReadByte();
var parent = _reader.ReadByte();
var walk_x = _reader.ReadInt16();
var walk_y = _reader.ReadInt16();
tmp = _reader.ReadByte();
byte height = (byte)(tmp & 0xF8);
byte actordir = (byte)(tmp & 0x07);
var data = new ObjectData(objId);
data.Position = new Point((short)(8 * x), (short)(8 * y));
data.Width = (ushort)(8 * width);
data.Height = height;
data.Parent = parent;
data.ParentState = parentState;
data.Walk = new Point(walk_x, walk_y);
data.ActorDir = actordir;
room.Objects.Add(data);
var nameOffset = _reader.ReadByte();
var size = nameOffset - 6 - 13;
ReadVerbTable(data, size);
data.Name = ReadObjectName(it, nameOffset);
// read script
size = (int)(it.Current.Offset + it.Current.Size - 6 - _reader.BaseStream.Position);
data.Script.Data = _reader.ReadBytes(size);
data.Script.Offset = nameOffset + data.Name.Length + 1;
SetObjectImage(room.Image.ZPlanes.Count, objImages, data);
}
break;
default:
{
var data = _reader.ReadBytes((int)it.Current.Size - 6);
System.Diagnostics.Debug.WriteLine("Ignoring Resource Tag: {0} (0x{1:X2}{2:X2}) [{3}]",
it.Current.Tag, (int)it.Current.Tag[0], (int)it.Current.Tag[1],
string.Join(",", data.Select(b => b.ToString("X2"))));
}
break;
}
}
return room;
}