Tiny 3DS loader

[virtual]

hi
a tiny 3ds warpper draw 1 object wih 1 texture
in fact this is my translation of a c++ code has been found in www.codesampler.com

Unit Mini3ds;

interface

uses windows,opengl;


const
   MAX_GEO = 10000;
type

// Vertex
   Vertex  = record
        x,
        y,
        z : single;
        end;

// texture
   mapcoord = record
        u,
        v : single;
        end;

// index
   polygon = record
        a,
        b,
        c : integer;
        end;

// 3d object structure
   _object = record
        name : array[0..21] of char;
        numVerts : integer;
        numPolys : integer;
        v : array [0..MAX_GEO] of vertex;
        p : array [0..MAX_GEO] of polygon;
        m : array [0..MAX_GEO] of mapcoord;
        end;

// 3ds object
  T3DS = object
   public
    procedure Load(_fn : string);
    procedure Draw();
    procedure free();
   public
    obj : _object;
   end;


implementation

{ T3DS }

procedure T3DS.Load(_fn: string);
var
_file : file of byte;
 i  : integer;
 chunkID : short;
 chunkLength  : integer;
 tmp       : char;
 useless  : short;
 from      : integer;
_fsize     : integer;
 label begincase;
begin

    AssignFile(_file,_fn);
    Reset(_file);
  _fsize := filesize(_file);

  while ( filepos(_file) < _fsize) do
  begin
     begincase:
     BlockRead(_file,chunkID,2);
     BlockRead(_file,chunkLength,4);

    case chunkID of

     $4d4d : begin end;
     $3d3d : begin end;
     $4000 :
  	for i:=0 to 20-1 do
	 begin
	       Blockread (_file,tmp, 1);
                       obj.name[i]:=tmp;
                if pointer(tmp) = NIL then
              goto begincase;
      end;

     $3f80 :begin end;
     $4100 :begin end;
     $4110 :
         begin
   	BlockRead(_file,obj.numVerts,2);
    	for i:=0 to obj.numVerts - 1 do
                    begin
	         BlockRead (_file, obj.v[i].x,4);
                         BlockRead (_file, obj.v[i].y,4);
    	         BlockRead (_file, obj.v[i].z,4);
 	    end;
        end;

     $4120 :
      begin
	BlockRead (_file,obj.numPolys, 2);
                  for i:=0 to obj.numPolys - 1 do
                     begin
	        BlockRead (_file,obj.p[i].a, 2);
    	        BlockRead (_file,obj.p[i].b, 2);
	        BlockRead (_file,obj.p[i].c, 2);
	        BlockRead (_file,useless, 2);
	     end;
      end;

     $4140 :
      begin
   	BlockRead (_file , useless, 2);
    	  for i:=0 to obj.numVerts - 1 do
	     begin
	         BlockRead (_file , obj.m[i].u , 4);
                         BlockRead (_file , obj.m[i].v , 4);
	     end;
      end;
    else
    begin
         from := filePos(_file);
         seek(_file,from + chunkLength-6);
     end;
    end;
  end;
 closefile(_file);
end;

procedure T3DS.Draw();
var i : integer;
begin

   glBegin(GL_TRIANGLES);
     for i:=0 to obj.numPolys - 1 do
        begin
             glTexCoord2f( obj.m[ obj.p[i].a ].u,obj.m[ obj.p[i].a ].v);
             glVertex3f( obj.v[ obj.p[i].a ].x,
                              obj.v[ obj.p[i].a ].y,
                              obj.v[ obj.p[i].a ].z);

             glTexCoord2f( obj.m[ obj.p[i].b ].u,obj.m[ obj.p[i].b ].v);
             glVertex3f( obj.v[ obj.p[i].b ].x,
                              obj.v[ obj.p[i].b ].y,
                              obj.v[ obj.p[i].b ].z);

             glTexCoord2f( obj.m[ obj.p[i].c ].u,obj.m[ obj.p[i].c ].v);
             glVertex3f( obj.v[ obj.p[i].c ].x,
                              obj.v[ obj.p[i].c ].y,
                              obj.v[ obj.p[i].c ].z);
        end;

 glEnd();

end;

procedure T3DS.free;
begin
 //
end.

virtual