FF Studio

A Windows tool for opening closed Black Ops III fastfiles (.ff). View the assets inside, edit scripts, textures and Lua, and build a new drop-in .ff. Use it to inspect, fix or maintain mods whose source isn't available.

Download

Get FFStudio.exe from Releases. No install needed.

GSC script decompile and build also need ACTS and the BO3 Mod Tools (see Requirements).

Usage

1. Click Browse mods… and pick a fastfile, or paste a .ff path and click Open FF.
2. Click an asset to view it. Use ⬇ on a row to export it.
3. Edit a script and click Build to write a new .ff. Install Studio ff swaps it in for the original; Restore original puts the original back.

What it can do

Asset	View	Edit
Scripts (GSC/CSC)	Decompiled source with symbols, go to definition, find references, renaming of hashed names	Edit and rebuild the .ff
Images	Preview (BC1/BC3/BC4/BC5/BC7, RGBA8), inline or streamed from .xpak. Export PNG	Replace (BC1/BC3/RGBA8, same size)
Lua (HKS rawfiles)	Disassembly and pseudo-Lua	Recompile and splice back (needs hksc)
Models and meshes	3D view with skeleton and LODs. Export OBJ	—
Animations	Keyframe playback on the model's skeleton and skinned mesh	—
FX	Element tree, sampled curves, decompiled .efx. Export .efx	—
Materials, techsets	Textures used; DXBC shader breakdown	—
Fonts	Glyph preview. Export TTF	—
String tables	Table grid	—
Other rawfiles, key-value pairs	Text, hex or field view. Export raw	—

Also:

• Asset list by type, with mod-added assets marked separately from base-game ones.
• Mods made of several fastfiles (e.g. core_mod.ff + zm_mod.ff) open as one workspace.
• Base-game fastfiles can be browsed (read-only).

What it can't do

• No viewer for: weapons, attachments and camos; sounds; physics presets; vehicles; AI, characters, animation state machines and behaviour trees; script bundles; lights and lens flares; tracers; xcams; map data (world geometry, collision, map entities, navmesh); localized strings. These show in the asset counts only.
• Only scripts, textures and Lua can be edited.
• Base-game fastfiles can't be edited.
• Geometry stored in a different fastfile isn't shown unless it's in a shared base-game fastfile. Collision meshes aren't drawn.
• Animation root motion isn't played.
• FX curves are the baked samples, not the FX editor's original control points.
• Pseudo-Lua shows control flow as labels and gotos, not rebuilt if/while blocks.
• BC5 and BC7 textures can't be replaced.
• String table cells whose hash matches more than one string are marked as a best guess.

Requirements

Windows. The exe includes Python and all packages. These are separate downloads, and are only needed for the features listed:

Tool	Needed for	Setup
ACTS v3.2.1	GSC decompile and build	Download acts.zip and extract it so acts\bin\acts.exe is next to FFStudio.exe (or in the repo root when running from source).
BO3 Mod Tools	GSC build	Install from Steam. Found automatically.
hksc	Lua recompile	Build it for T7 and put hksc.exe in a tools\ folder next to the exe (or in the repo root), or set HKSC_PATH.

The app lists anything missing on startup with what to do.

Running from source

Needs Python 3.8+.

pip install -r requirements.txt
python src/ffstudio_app.py

src/ffstudio_app.py opens a desktop window; src/ffstudio.py runs the browser version. To build the exe, run packaging\build_exe.bat (output: dist\FFStudio.exe). See docs/PACKAGING.md.

src/          application code and UI
packaging/    exe build script and PyInstaller spec
docs/         packaging notes, icon and screenshots

A _studio_cache\ folder is created next to the exe (or in src\ from source) for decompile caches. It's safe to delete.

License

MIT. three.js (src/three.min.js) is MIT licensed. ACTS, hksc and the BO3 Mod Tools are not included.

FF Studio is not affiliated with or endorsed by Activision or Treyarch.