      switch(tet_index)
        {
            case 0:
                ret.index0 = 8;
                ret.index1 = 9;
                ret.index2 = 0;
                ret.index3 = 1;
                break;
            case 1:
                ret.index0 = 8;
                ret.index1 = 9;
                ret.index2 = 1;
                ret.index3 = 5;
                break;
            case 2:
                ret.index0 = 8;
                ret.index1 = 9;
                ret.index2 = 5;
                ret.index3 = 4;
                break;
            case 3:
                ret.index0 = 8;
                ret.index1 = 9;
                ret.index2 = 4;
                ret.index3 = 0;
                break;
            case 4:
                ret.index0 = 8;
                ret.index1 = 10;
                ret.index2 = 2;
                ret.index3 = 3;
                break;
            case 5:
                ret.index0 = 8;
                ret.index1 = 10;
                ret.index2 = 3;
                ret.index3 = 7;
                break;
            case 6:
                ret.index0 = 8;
                ret.index1 = 10;
                ret.index2 = 7;
                ret.index3 = 6;
                break;
            case 7:
                ret.index0 = 8;
                ret.index1 = 10;
                ret.index2 = 6;
                ret.index3 = 2;
                break;
            case 8:
                ret.index0 = 8;
                ret.index1 = 11;
                ret.index2 = 3;
                ret.index3 = 0;
                break;
            case 9:
                ret.index0 = 8;
                ret.index1 = 11;
                ret.index2 = 0;
                ret.index3 = 4;
                break;
            case 10:
                ret.index0 = 8;
                ret.index1 = 11;
                ret.index2 = 4;
                ret.index3 = 7;
                break;
            case 11:
                ret.index0 = 8;
                ret.index1 = 11;
                ret.index2 = 7;
                ret.index3 = 3;
                break;
            case 12:
                ret.index0 = 8;
                ret.index1 = 12;
                ret.index2 = 1;
                ret.index3 = 2;
                break;
            case 13:
                ret.index0 = 8;
                ret.index1 = 12;
                ret.index2 = 2;
                ret.index3 = 6;
                break;
            case 14:
                ret.index0 = 8;
                ret.index1 = 12;
                ret.index2 = 6;
                ret.index3 = 5;
                break;
            case 15:
                ret.index0 = 8;
                ret.index1 = 12;
                ret.index2 = 5;
                ret.index3 = 1;
                break;
            case 16:
                ret.index0 = 8;
                ret.index1 = 13;
                ret.index2 = 1;
                ret.index3 = 0;
                break;
            case 17:
                ret.index0 = 8;
                ret.index1 = 13;
                ret.index2 = 0;
                ret.index3 = 3;
                break;
            case 18:
                ret.index0 = 8;
                ret.index1 = 13;
                ret.index2 = 3;
                ret.index3 = 2;
                break;
            case 19:
                ret.index0 = 8;
                ret.index1 = 13;
                ret.index2 = 2;
                ret.index3 = 1;
                break;
            case 20:
                ret.index0 = 8;
                ret.index1 = 14;
                ret.index2 = 5;
                ret.index3 = 6;
                break;
            case 21:
                ret.index0 = 8;
                ret.index1 = 14;
                ret.index2 = 6;
                ret.index3 = 7;
                break;
            case 22:
                ret.index0 = 8;
                ret.index1 = 14;
                ret.index2 = 7;
                ret.index3 = 4;
                break;
            case 23:
                ret.index0 = 8;
                ret.index1 = 14;
                ret.index2 = 4;
                ret.index3 = 5;
                break;    
        }