NEXUS Splats for Nuke

Edit Gaussian Splats from inside Nuke — one click out to NEXUS GS Viewer, one click back.

📬 Building AI × VFX pipeline tools. Follow along and get new tools + breakdowns first → Patrick Crucke on LinkedIn

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What it does

Formerly Nexus x Nuke (1.0 and 1.1). Same plugin, same NexusXnuke/ folder in .nuke, so nothing changes for an existing install — the name now follows the family (NEXUS Passes for Nuke, NEXUS Splats for Unreal).

NEXUS Splats for Nuke bridges Nuke and NEXUS GS Viewer, the open-source Gaussian Splatting viewer & editor. From a single node in your script:

1. Edit in NEXUS — opens your splat file (.ply, .spz, .splat, .ksplat) in the viewer
2. Clean it up there — keep/erase shapes, eraser brush, splat selection, bake — then hit the viewer's → Nuke button
3. Import result — the edited splats land back in your script as a GeoImport, ready to view (select it, V, then Tab for 3D)

Perfect companion to Marble-x-Nuke: generate a world with Marble, clean and previz it with NEXUS, composite in Nuke — without ever leaving your pipeline.

Why it matters

Splat scans and generated worlds arrive noisy — floaters, stray ground, blown edges. Cleaning them used to mean exporting, hunting for a standalone tool, re-importing by hand. Now it's a round-trip built into the node graph: the file paths are managed for you, the viewer opens on the right file, and the result snaps back next to the node that sent it.

Installation

1. Install NEXUS GS Viewer

Grab it from the releases page (Windows, macOS, Linux). Launch it once — on Windows it registers itself so the plugin finds it automatically.

2. Copy the plugin

Copy the NexusXnuke/ folder into your .nuke directory:

OS	Path
Windows	C:\Users\<YourName>\.nuke\NexusXnuke\
macOS	/Users/<YourName>/.nuke/NexusXnuke/
Linux	/home/<YourName>/.nuke/NexusXnuke/

3. Register the plugin

Open (or create) init.py inside your .nuke directory and add:

import nuke, os
nuke.pluginAddPath(os.path.join(os.path.expanduser("~/.nuke"), "NexusXnuke"))

That's it. A NEXUS Splats menu appears in the Nodes toolbar.

Usage

1. Create a NEXUS Edit node from the NEXUS Splats menu
2. Set GS file — or select your GeoImport/ReadGeo and click Grab from selected
3. Click Edit in NEXUS → the viewer opens on your file
4. Clean, animate, playblast… then click the viewer's → Nuke button
5. Back in Nuke, click Import result → a NexusResult GeoImport appears (select, V, Tab)

Camera round-trip — Import camera creates an animated Nuke Camera from the shot you blocked in NEXUS (written next to the round-trip file when you click → Nuke with ≥2 keys); Send camera exports the selected Nuke Camera (ZXY) and replays it on the splats in the viewer. The .chan focal is written for Nuke's default 24.576 mm horizontal aperture, so an unmodified Camera node matches the playblast frame-for-frame (verified in Nuke 17; requires NEXUS GS Viewer ≥ 0.13.2 or NEXUS 4D Viewer ≥ 0.4.0).

Playblast — renders the scene through the viewer's headless CLI (saved animation or auto-orbit, 1080p at your project fps) and drops the MP4 into a Read node when done.

The Edited output path defaults to <source>_nexus.ply; the NEXUS app path is auto-detected (registry on Windows, /Applications on macOS) and remembered between sessions. You can also set the NEXUS_GS_VIEWER environment variable.

Requirements

• Nuke 15+ (Commercial, Indie or Non-Commercial) — tested on 15.2 and 17.0
• NEXUS GS Viewer 0.13 or newer (the --roundtrip contract)
• No external Python packages

Troubleshooting

Problem	Solution
"NEXUS GS Viewer not found"	Set the NEXUS app knob to the executable (or the NEXUS_GS_VIEWER env var)
"No edited file yet" on import	In the viewer, click the → Nuke button first — it writes the round-trip file
Edited splats lost their view-dependent shading	Expected: NEXUS cleanup rebuilds splats without SH>0 harmonics — fine for previz
The viewer opens but without the → Nuke button	Update NEXUS GS Viewer to 0.13+

More traps (plugin path levels, stale __pycache__, rotation order and aperture of the .chan, the detached viewer process) in docs/PITFALLS.md.

License

Released under the MIT License. Free to use, modify, and ship in commercial work.

Credits

• NEXUS GS Viewer — the editor this plugin talks to
• Foundry — for Nuke, the compositing standard

Built and maintained by SINAI R&D — Patrick Crucke.

If this project saved you time, a ⭐ on the repo goes a long way.