I start today the LOD management for my forts and i do some test to understand how it works.
The Lua code in graphics files are:
I think I found what this NUMBER is, it is related to the greatest width of the object. I use F11 view without zoom.
Some screens test (I used the model of another fort to know when I changed lod, example fort_02 use as LOD01 for fort_01)
LOD at 1600:
Vaux (distance approx. 140m)
Douaumont (distance approx. 330m)
Merger of the two screens:
We see that the displayed size is somewhat similar.
Vaux has a dimension of 234m x 150m = approx 35000 m²
Douaumont a dimension of 556m x 474m = approx 264000 m²
It does not appear to have correlativity with the surface (35000/140=250 is not equal 264000/330=800), but if use the greatest width it seems to be correlated (234/140=1,67 and 556/320=1,68).
The display of the LOD distance seems to correspond approximately to: Greatest width / NUMBER x 1000 = Distance in meters.
LOD Number at 1600:
Douaumont: 556/1600x1000 = 348 m (340m in game)
Vaux: 234/1600x100 = 146 m (140m in game)
Just to confirm, LOD NUMBER at 800:
Distance is approx. 670 m in game => 556/800x1000= 695 m, not exact but similar.
I also tested with my casemate (99m x 35m), with LOD NUMBER at 800, the distance in game is approx. 120 m => 99/800x1000= 124 m
Therefore to determine the lod number, must be: LOD NUMBER = Greatest width of the object / Desired distance x 1000
If other modelers want to test with their objects.