converts a THREE.geometry to OBJ

toOBJ

    var str = "# object mesh \n";
    g.toIndexed();

    var vs = g.getAttribute("position").array;
    var ind = g.getIndex().array;

    var precision = 6;
    for( var i = 0 ; i < vs.length; i+=3 ){
        str += "v " + vs[i].toFixed(precision) + " " + vs[i+1].toFixed(precision) + " " + vs[i+2].toFixed(precision)+ "\n";
    }
    str +="# " + (ind.length / 3 ) +" vertices";
    str += "\n";
    str += "g mesh";
    for( i = 0 ; i < ind.length; i+=3 ){
        str += "f " + ind[i]  + " " + ind[ i + 2 ] + " " + ind[ i + 1 ]+ "\n";
    }
    str +="# " + (ind.length / 3 ) +" faces";