unit Unit3DS_11;

interface

uses Windows, Classes;

type point = record
        k:integer;
        x,y,z,nx,ny,nz:Single;
     end;

type face = record
        a,b,c:integer;
     end;

type T3DObject = class(TObject)
  private
        // Nothing here at moment
  public
     PointCount, FaceCount: Integer;
     ObjectName:String;
     p:array of point;
     f:array of face;
     constructor Create;
     destructor Destroy; override;
     procedure Draw;
end;

type TChunk = class(TObject)
  private
     function ReadObjectString:String;
  public
     Id: word;
     iBytesReaded, ChunkLength : Integer;
     iFileHandle, iFileLength, ObjCount:Integer;
     Objects:array of T3DObject;
     function ReadChunk: Integer;
     function ReadBuffer(var Buffer; Count:Integer):Integer;
     procedure AddObject(ObjNr: Integer);
     procedure Load3Data;
     constructor Create;
     destructor Destroy; override;
end;

type T3DModel = class(TObject)
  private
     ObjCount:Integer;
     RootChunk:TChunk;
     Objects:array of T3DObject;
  public
     constructor Create;
     destructor Destroy; override;
     procedure LoadFromFile(const FileName:string);
     procedure Clone3Data;
     procedure Draw;
end;

implementation

uses SysUtils, OpenGL;

constructor T3DObject.Create;
begin
     inherited;
     ObjectName:='';
     PointCount:=0; FaceCount:=0;
     p:=nil;
     f:=nil;
end;

destructor T3DObject.Destroy;
begin
        Finalize(p);
        Finalize(f);
        inherited;
end;

procedure T3Dobject.Draw;
var i:integer;
begin
        for i:=0 to FaceCount-1 do begin
                   glBegin(GL_POLYGON);
      glVertex3f(p[f[i].a].x,p[f[i].a].y,p[f[i].a].z);
      glVertex3f(p[f[i].b].x,p[f[i].b].y,p[f[i].b].z);
      glVertex3f(p[f[i].c].x,p[f[i].c].y,p[f[i].c].z);
                   glEnd();
end;  end;

constructor TChunk.Create;
begin
        inherited;
  iFileHandle:=0; iFileLength:=0; iBytesReaded:=0; ObjCount:=0; ChunkLength:=0;
  Id:=0;
        Objects:=nil;
end;

destructor TChunk.Destroy;
begin
        Finalize(Objects);
        inherited;
end;

function TChunk.ReadChunk: Integer;
begin
   iBytesReaded:=FileRead(iFileHandle, Id, 2);
   iBytesReaded:=iBytesReaded + FileRead(iFileHandle, ChunkLength, 4);
   Result:=iBytesReaded;
end;

function TChunk.ReadBuffer(var Buffer; Count: Integer): Integer;
begin
  Result:=FileRead(iFileHandle, Buffer, Count);
  iBytesReaded:=iBytesReaded + Result;
end;

function TChunk.ReadObjectString:String;
var //S:String;
    C:Char;
    i:integer;
    SStr:ShortString;
begin
        C:=#255; i:=0;
   while (C<>#0) {and (i<=20)} do begin
     iBytesReaded:=iBytesReaded+FileRead(iFileHandle, C, 1);
     SStr[i+1]:=C;
     Inc(i);
   end;
  SetLength(Result, I-1);
  Move(SStr[1], Result[1], I-1);
end;

procedure TChunk.AddObject(ObjNr:Integer);
begin
        SetLength(Objects,ObjNr);
        Objects[ObjNr].Create;
end;

procedure TChunk.Load3Data;
var i,x: Integer;
begin
        while (iBytesReaded < iFileLength) do begin
        ReadChunk;
case Id of
      $4D4D: begin
      // MAIN CHUNK
      //  ShowMessage('Found $4D4D at: ' + IntToStr(iBytesReaded) + '  length: ' + IntToStr(ChunkLength));
             end;

      $3D3D: begin
      // 3D EDITOR CHUNK
      //  ShowMessage('Found $3D3D at: ' + IntToStr(iBytesReaded) + '  length: ' + IntToStr(ChunkLength));
        end;

      $4000: begin
      // OBJECT BLOCK
      inc(ObjCount);
      AddObject(ObjCount);
      Objects[ObjCount].ObjectName:=ReadObjectString; // PROPERTY USE ???!!!
      //  ShowMessage(ObjectName);
        end;

      $4100: begin
      // 3D Data Chunk (kb)
             end;

      $4110: begin  // VERTICES LIST
         with Objects[ObjCount] do begin
      ReadBuffer(PointCount, 2);
      SetLength(p,PointCount);
            for i:=0 to PointCount-1 do begin
              ReadBuffer(p[i].x,4);
              ReadBuffer(p[i].y,4);
              ReadBuffer(p[i].z,4);
    end;    end;     end;

          $4120: begin //  FACES DESCRIPTION
     with Objects[ObjCount] do begin
        ReadBuffer(FaceCount, 2);
        SetLength(f,FaceCount);
                for i:=0 to FaceCount-1 do begin
            ReadBuffer(f[i].a, 2);
            ReadBuffer(f[i].b, 2);
            ReadBuffer(f[i].c, 2);
            ReadBuffer(x, 2);
           end;     end;    end;
else
iBytesReaded:=FileSeek(iFileHandle,ChunkLength-6,1);  end;
     end; // while end;
end;

constructor T3DModel.Create;
begin
        inherited;
     ObjCount:=0;
     //RootChunk:=nil;
     Objects:=nil;
end;

destructor T3DModel.Destroy;
begin
        Finalize(Objects);
        inherited;
end;

procedure T3DModel.LoadFromFile(const FileName:string);
var iFileHandle, iFileLength: Integer;
begin
iFileHandle:=0; //iFileLength:=0;
    try
      iFileHandle := FileOpen(FileName, fmOpenRead);  
    finally
      iFileLength := FileSeek(iFileHandle,0,2);
      FileSeek(iFileHandle,0,0);
      RootChunk:=TChunk.Create;
      RootChunk.iFileHandle:=iFileHandle;
      RootChunk.iFileLength:=iFileLength;
      RootChunk.Load3Data;
      Clone3Data;
      RootChunk.Free;   
      RootChunk.Destroy;
      //ShowMessage('RootChunk Destroyed Successfully');
      FileClose(iFileHandle);
    end;
end;

procedure T3DModel.Clone3Data;
var i,j:integer;
begin
   ObjCount:=RootChunk.ObjCount;
   SetLength(Objects,ObjCount);
   for i:=1 to ObjCount do begin
    Objects[i].Create;
        with Objects[i] do begin
        PointCount:=RootChunk.Objects[i].PointCount;
        FaceCount:=RootChunk.Objects[i].FaceCount;
        SetLength(p,Objects[i].PointCount);
        SetLength(f,Objects[i].FaceCount);
        ObjectName:=RootChunk.Objects[i].ObjectName;
    for j:=0 to PointCount-1 do p[j]:= RootChunk.Objects[i].p[j];
    for j:=0 to FaceCount-1 do f[j]:= RootChunk.Objects[i].f[j];
  end;
end;
end;

procedure T3DModel.Draw;
var i:integer;
begin
        for i:=1 to ObjCount do Objects[i].Draw;
end;

end.