What are LOD's? Are those modeling programs free? I wonder what Dave Snow uses to make buildings. I'm a dummy when it comes to 3D modeling, or even complex reskins of locomotives and rolling stock. There are some buildings on 3D warehouse that are low poly, I think I uploaded a Hampton Inn to the DLS a couple years ago which looks low poly. Then there was this Embassy Suites on the warehouse with a detailed interior and I think it was thousands of polys. I didn't convert that one. I had Dave make me an Embassy Suites more recently and it doesn't have any interior. It's probably low poly.
A simple explanation of LODs.
If you create an object for Trainz 2012 (build 3.5-3.7), you don't need to create LODs. Your object won't have LOD errors. Some authors use this workaround to upload their objects to the DLS without errors. Even without LODs, the game will struggle and may not perform well with many of those objects.
Starting with Trainz TANE, if your object has a build higher than 4.2 and the mesh has more than 500 polygons, you must create LODs.
If you create an object with 4000 polygons, for example, that would be your first LOD, or LOD0. Then, to create LOD1, you need to reduce the polygon count by at least 20%, and so on until the final LOD, which must have fewer than 500 polygons.
Lod0 ................4000 polys
Lod1 4000-20%: ......3200 polys
Lod2 3200-20%: ......2560 polys
Lod3 and last one less than 500 polys
Note that Lod0 is the one that will be seen in the foreground, Lod1 may be visible from 100 meters or more, depending on the configuration, and Lod2 and Lod3 will be very small and almost invisible.
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