Bethesda LOD File Generator

Take in the sights of your world!

About

A simple command-line drag-and-drop utility that allows for the creation and extraction of .lod (LODSettings) files for supported Bethesda games.

The creation of .lod files is the main reason I made this program, however it also supports extracting data from existing ones. This is only useful if you want a readable version of the data stored within the file to see what settings are used, or if you want to make sure your .lod files were properly generated.

DISCLAIMER: This is not an official tool nor is it endorsed by Bethesda.

Game Support

Bethesda games developed after the release of Skyrim use .lod files to help generate LOD meshes for worldspaces.

Game	Creation	Extraction
Skyrim LE	Supported	Supported
Skyrim SE	Supported	Supported
Fallout 4	Supported	Supported
Fallout 76	Not Supported	Supported
Starfield	Not Supported	Supported

NOTES

Technically the creation of .lod files for Fallout 76 is supported but there's no point adding support for the full size value of 512 as users are not allowed to create proper mods for the game.

Starfield extraction support was completed on 2024-07-14. For creation support I need to find out how the size value stored in the files are gathered/calculated before I start working on it.

LODSettings File Structure

The file structure for those that are interested in how the data is stored within the .lod files. Use a program like HxD if you want to look at the files yourself.

Skyrim/Fallout 4

Initial info gathered from UESP. Further info gathered by me during the creation of this program.

struct lodsetting
{
    signed short west;    // 00 - The westernmost cell of the worldspace
    signed short south;   // 02 - The southernmost cell of the worldspace
    signed int size;      // 04 - A power of 2 less than or equal to 256
                          //      (How many cells in the North/East direction to generate LOD for)
    signed int lowLOD;    // 08 - Lowest LOD level (4, 8, 16, 32; Default: 4)
    signed int highLOD;   // 0C - Highest LOD level (4, 8, 16, 32; Default: 32)
};

Example - DLC01SoulCairn.lod

CC FF CD FF 00 01 00 00 04 00 00 00 20 00 00 00

	West	South	Size	Lowest LOD	Highest LOD
Bytes	CC FF	CD FF	00 01 00 00	04 00 00 00	20 00 00 00
Value	-52	-51	256	4	32

Fallout 76

Same format as a Skyrim/Fallout 4 .lod file but can support size values up to 512.

struct lodsetting
{
    signed short west;    // 00 - The westernmost cell of the worldspace
    signed short south;   // 02 - The southernmost cell of the worldspace
    signed int size;      // 04 - A power of 2 less than or equal to 512
                          //      (How many cells in the North/East direction to generate LOD for)
    signed int lowLOD;    // 08 - Lowest LOD level (4, 8, 16, 32; Default: 4)
    signed int highLOD;   // 0C - Highest LOD level (4, 8, 16, 32; Default: 32)
};

Example - Appalachia.lod

42 FF 23 FF 00 02 00 00 04 00 00 00 20 00 00 00

	West	South	Size	Lowest LOD	Highest LOD
Bytes	42 FF	23 FF	00 02 00 00	04 00 00 00	20 00 00 00
Value	-190	-221	512	4	32

Starfield

A slightly updated format compared to older Creation Engine .lod files.

I'm still gathering info on how exactly these files are structured.

struct lodsetting
{
    signed int objBoundMinX;  // 00 - The worldspace object bounds' Min X value
    signed int objBoundMinY;  // 04 - The worldspace object bounds' Min Y value
    signed int size;          // 08 - Using Math.Abs(a - b) using the two largest values from Min/Max
                              //      gives about the right results but there are inconsistencies in
                              //      in some .lod files that makes me doubt this is 100% correct
    signed int unk1;          // 0C - Engine might ignore these values? 00000000
    signed int unk2;          // 10 - Engine might ignore these values? 00000000
};

Example - NewAtlantis.lod

DD FF FF FF C5 FF FF FF 88 00 00 00 00 00 00 00 00 00 00 00

	objBound Min X	objBound Min Y	Size	unk1	unk2
Bytes	DD FF FF FF	C5 FF FF FF	88 00 00 00	00 00 00 00	00 00 00 00
Value	-35	-59	136	0	0