<?php
# Starcraft 2 M3 to OBJ Converter v0.1
# Currently Imports: Mesh, Texture Map
# Does Not Yet Support: Bones, Materials, Geosets, Animations
#########################
# $argv[1] is a user editable field,  
#########################
   $temp = explode(".m3", $argv[1]);
     $file = $argv[1];
     $path = $temp[0];
     echo("Exporting Model $path.m3 to $path.obj\n\n");
     $file = fopen($file, 'rb') or die("Failed to open $file!\n");
     if(fread($file,4) != "33DM") die("Failed! File is not a StarCraft 2 model!\n");
     fseek($file, 4); # find where tags start
     $index = unpack(V, fread($file, 4));
     # search for __8U "5F 5F 38 55" tag for vertex offset
     $offset = $index[1];
     while(1){
         fseek($file, $offset+16);
         $string = fread($file, 4);
         if ($string == '__8U'){
             $offset+=20;
             break;
         }
         $offset++;
     }
     fseek($file, $offset);
     $index = unpack(V, fread($file, 4));
      
     fseek($file, $offset+4);
     $maxVerts = unpack(V, fread($file, 4)); # maximum extents
     $maxVerts[1] = $maxVerts[1] + $index[1];
      
     fseek($file, $offset+32); # face data
     $indexFaces = unpack(V, fread($file, 4));
     fseek($file, $offset+36);
     $maxFaces = unpack(V, fread($file, 4));
     $maxFaces[1] = $maxFaces[1]*2 + $indexFaces[1];
    
     $i = 0;
     $offset = $index[1];
     while(1){
       if ($offset >= $maxVerts[1]) break;
       for($j=0;$j<3;$j++){ # read verts
         fseek($file, $offset);
         $temp = unpack(f, fread($file, 4));
         $vert[$i] = $temp[1];
         $offset +=4;
         $i++;
       }
       $offset+=12;
       for($j=0;$j<2;$j++){ # read UV
         fseek($file, $offset);
         $temp = unpack(v, fread($file, 2));
         $uv[$k] = $temp[1] / 2046;
         $offset +=2;
         $k++;
       }
       fseek($file, $offset); # some model files have 4 null bytes after uv, let's hope there's no more special cases
       if (fread($file,1) != "FF") $offset+=4;
       $offset+=4;
     }
     $i=0;
     $offset = $indexFaces[1];
     while(1){ # read faces
       if ($offset >= $maxFaces[1]) break;
       fseek($file, $offset);
       $temp = unpack(v, fread($file, 2));
       $face[$i]=$temp[1];
       $i++;
       $offset+=2;
     }
     $out = fopen($path . ".obj", 'w+');
     for($i=0; $i<sizeof($vert); $i+=3){
       fwrite($out, "v " . $vert[$i] . " " . $vert[$i+1] . " " . $vert[$i+2] . "\n");
     }
     for($i=0; $i<sizeof($uv); $i+=2){
       fwrite($out, "vt " . $uv[$i] . " " . $uv[$i+1] . "\n");
     }
     for($i=0; $i<sizeof($face); $i+=3){
       fwrite($out, "f " . ($face[$i]+1) . "/" . ($face[$i]+1) . " " . ($face[$i+1]+1) . "/" . ($face[$i+1]+1) . " " . ($face[$i+2]+1) . "/" . ($face[$i+2]+1) . "\n");
     }
     fclose($out);
     echo("Done!\n\n");
?>