se-cmd

Converts Skyrim's assets to FBX and back: meshes, collision, skeletons, ragdolls and animations. Drop files on it and it works out what they are.

Using it

Download the archive from Releases, unzip it anywhere, and drag files or folders onto se-cmd.exe. Everything it produces lands in an out folder beside what you dropped, with a conversion-log.txt next to it saying what each input was taken to be and what came of it.

The same thing from a terminal:

se-cmd convert <paths...> [-o out] [-m meshes] [-t skeleton.hkx]
se-cmd <paths...>              # the verb is optional

what you drop	what you get
a creature's folder	one FBX: its skeleton, its bodies, its ragdoll and every animation its project has
a .nif	that mesh as an FBX, with its collision
a skeleton.hkx	its rig and ragdoll as an FBX
an animation .hkx	the clip over the rig found above it
an .fbx	back into the files the game reads — .nif, skeleton.hkx, animation packfiles and the cache entries that address them
a folder of anything	each creature whole, then every other file it holds

Nothing is guessed at. Each file is opened and asked what it is, because the extension does not say: a .nif may be a rock, a windmill, a skinned body or an actor's skeleton, and a .hkx may be a rig or a clip.

What it needs to do the whole job

Two things are found automatically when they are there, and named when they are not:

• -m, the extracted meshes folder holding animationdatasinglefile.txt. A creature's travel — how far a walk carries it — is in that cache and not in the animation, so without it a creature's clips are skipped. It is looked for above whatever you dropped.
• -t, a skeleton.hkx to write the Havok half into. A Havok packfile is a thousand objects of scaffolding, so one is edited from an original rather than built from nothing. Re-importing a creature you exported, that is its own skeleton.hkx, found above the FBX.

Where either is missing the log says so and that part is skipped rather than half-written.

What a converted file says about itself

The NIF header's Process Script records the tool and the library — se-cmd 0.1.10.0, NIFBX 1.6.1 — and the FBX's Creator says the same. Author is left alone: that is where a NIF keeps the name of whoever made it, and 1,046 of the game's 1,106 meshes use it.

The other commands

convert covers the conversion, in both directions, for anything it is handed: a NIF, an HKX, an FBX, or a creature's folder. It asks the file what it is, so there is nothing for a command naming the direction to do. These are the jobs that are not conversions:

findnpc	say which files a creature is made of, without converting any of them
exportnpc	gather the files a record configures, out of the archives, into one FBX
retarget	a creature's Havok project, forms and assets onto another actor

Where the work is

Almost none of it is here. This is the command line; the conversion lives in its own repositories and arrives as a package:

NIFBX	NIF ↔ FBX, and the specs and corpus tests behind it
SKAssets	what an asset is made of, and a creature as one scene
HKSK	the Havok animation cache
HKFBX	Havok rigs and clips ↔ FBX
NIFSharp	reading and writing the NIF itself
LeanMeshIO	the FBX as a raw node tree

A change to the conversion belongs in one of those. This repository is the command line over them.

Building

dotnet build

The packages come from GitHub Packages, so a restore needs GITHUB_USERNAME and a GITHUB_TOKEN carrying read:packages; nuget.config takes them from the environment.

Licence

GPL-3.0-or-later.