private bool is3ds; // usd to shwo that the 4D4D magic number has been found
public IOReadResult Read(BinaryReader reader, ReadOptions options, IMeshBuilder builder)
{
ushort ChunkID;
String ChnkID = "";
UInt32 Clength;
MeshName = "";
hasMesh = false;
is3ds = false;
// Process the file - fails very politely when there is no more data
while (true)
{
//Get the Id of the next Chunk
try {
ChunkID = reader.ReadUInt16();
} catch {
break;
}
ChnkID = ChunkID.ToString("X");
//Get the size of the next chunk in chars
Clength = reader.ReadUInt32();
//Process based on Chunk ID
switch (ChnkID)
{
case "4D4D":
//This is a new file header
is3ds = true;
reader.ReadChars(10);
break;
case "3D3D":
//This is a new Object Header
reader.ReadChars(10);
break;
case "4000":
//This is an object Block. Store the name temporarily in case it is a mesh
List <char> name = new List <char>();
while (true)
{
char next = reader.ReadChar();
if (next == 0)
{
break;
}
name.Add(next);
}
MeshName = new String(name.ToArray <char>());
break;
case "4100":
// This is a new Mesh. Retrieve the name and add if the builder supports Metadata
builder.AppendNewMesh(false, false, false, false);
if (builder.SupportsMetaData)
{
builder.AppendMetaData("name", MeshName);
}
break;
case "4110":
// List of Vertexes
ushort VertexCount = reader.ReadUInt16();
for (int x = 0; x < VertexCount; x++)
{
double X = reader.ReadSingle();
double Y = reader.ReadSingle();
double Z = reader.ReadSingle();
builder.AppendVertex(X, Y, Z);
}
break;
case "4120":
// List of Triangles
ushort PolygonCount = reader.ReadUInt16();
for (int j = 0; j < PolygonCount; j++)
{
int a = reader.ReadInt16();
int b = reader.ReadInt16();
int c = reader.ReadInt16();
int flags = reader.ReadUInt16();
builder.AppendTriangle(a, b, c);
}
break;
case "4130":
// Mapping from Vertex to Material - retrieved but not currently used
List <char> mname = new List <char>();
while (true)
{
char next = reader.ReadChar();
if (next == 0)
{
break;
}
mname.Add(next);
}
string MatName = new String(mname.ToArray <char>());
ushort entries = reader.ReadUInt16();
for (int i = 0; i < entries; i++)
{
ushort face = reader.ReadUInt16();
}
break;
case "4140":
// List of UVs per vertex
ushort uvCount = reader.ReadUInt16();
for (ushort y = 0; y < uvCount; y++)
{
Vector2f UV = new Vector2f(reader.ReadSingle(), reader.ReadSingle());
builder.SetVertexUV(y, UV);
}
break;
default:
// Any other chunk - retrieved and not used - held in dump temporarily for debug
char[] dump = reader.ReadChars((int)Clength - 6);
break;
}
}
if (!is3ds)
{
return(new IOReadResult(IOCode.FileAccessError, "File is not in .3DS format"));
}
else if (!hasMesh)
{
return(new IOReadResult(IOCode.FileParsingError, "no mesh found in file"));
}
else
{
return(new IOReadResult(IOCode.Ok, ""));
}
}