thanks for your reply!
first i build the full model with ldd.
then i create step/groups in reverse order of construction removing pieces.
this is a simple pyramid. i build the blue floor, then the red floor and finally the yellow one. i create groups in reverse order, selecting bricks then hiding them.
this is what i get when i convert pyr.lxf with your utility:
0 FILE pyr_lxf
1 16 -30.000001192092896 -47.999998927116394 -150 1 0 0 0 1 0 0 0 1 pyr_lxf_0
1 16 -30.000001192092896 -23.999999463558197 -170.00000476837158 1 0 0 0 1 0 0 0 1 pyr_lxf_1
1 16 -30.000001192092896 0 -190.00000953674316 1 0 0 0 1 0 0 0 1 pyr_lxf_2
0 FILE pyr_lxf_0
1 14 30 -24 10 1 0 0 0 1 0 0 0 1 3001.dat
0 FILE pyr_lxf_1
1 4 30 -24 10 1 0 0 0 1 0 0 0 1 3001.dat
1 4 30 -24 50.000009536743164 1 0 0 0 1 0 0 0 1 3001.dat
0 FILE pyr_lxf_2
1 272 30 -24 10 1 0 0 0 1 0 0 0 1 3001.dat
1 272 30 -24 49.99999761581421 1 0 0 0 1 0 0 0 1 3001.dat
1 272 30 -24 90.00000715255737 1 0 0 0 1 0 0 0 1 3001.dat
the submodels/groups follow the reverse order, top-down (0-1-2) in this example.
as an option, it should be:
0 FILE pyr_lxf
1 16 -30.000001192092896 0 -190.00000953674316 1 0 0 0 1 0 0 0 1 pyr_lxf_2
1 16 -30.000001192092896 -23.999999463558197 -170.00000476837158 1 0 0 0 1 0 0 0 1 pyr_lxf_1
1 16 -30.000001192092896 -47.999998927116394 -150 1 0 0 0 1 0 0 0 1 pyr_lxf_0
(the rest is the same)
so now submodels/groups are in down-top order (2-1-0), following the right way of build it.
actually, i also add 0 STEP command between every submodel so i can check if everything is ok with ldcad and finally pass the file to lpub and create bi.
this is the final result:
0 FILE pyr_lxf
1 16 -30.000001192092896 0 -190.00000953674316 1 0 0 0 1 0 0 0 1 pyr_lxf_2
0 STEP
1 16 -30.000001192092896 -23.999999463558197 -170.00000476837158 1 0 0 0 1 0 0 0 1 pyr_lxf_1
0 STEP
1 16 -30.000001192092896 -47.999998927116394 -150 1 0 0 0 1 0 0 0 1 pyr_lxf_0
0 FILE pyr_lxf_0
1 14 30 -24 10 1 0 0 0 1 0 0 0 1 3001.dat
0 FILE pyr_lxf_1
1 4 30 -24 10 1 0 0 0 1 0 0 0 1 3001.dat
1 4 30 -24 50.000009536743164 1 0 0 0 1 0 0 0 1 3001.dat
0 FILE pyr_lxf_2
1 272 30 -24 10 1 0 0 0 1 0 0 0 1 3001.dat
1 272 30 -24 49.99999761581421 1 0 0 0 1 0 0 0 1 3001.dat
1 272 30 -24 90.00000715255737 1 0 0 0 1 0 0 0 1 3001.dat
i'm sorry i can't attach an lxf file, the interface allow me only images under 100k.
thanks, andrea.