VDBRender

OpenVDB Volume Ray Marcher for Nuke 17

A volume renderer that brings VDB files directly into Nuke's 2D compositing pipeline. Supports smoke, fire, explosions, clouds, and particle point clouds with physically-based lighting.

Created by Marten Blumen

Linux build available (community-contributed, unverified by the maintainer) — see LINUX_BUILD.md. The original project lives at github.com/bratgot/VDBmarcher — all plugin source is unmodified upstream code by Marten Blumen; if you find VDBRender useful, support the original author (see below). Linux port by Soup Kitchen Films, developed with the assistance of Claude (Anthropic).

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Features

Rendering

• Ray marching with HDDA empty-space skipping
• Adaptive step size for quality/speed balance
• Deep output for volumetric compositing
• Render region for fast iteration
• Proxy resolution modes (75%, 50%, 25%)
• Stochastic multi-sample anti-aliasing

Shading & Colour

• Lit, greyscale, heat, cool, blackbody, custom gradient, and explosion modes
• CIE 1931 blackbody (accurate 500K–40000K, Kang et al. 2002)
• Chromatic extinction (per-channel σt for Rayleigh-like scattering)
• Cd (colour) grid support for scatter albedo

Phase Functions

• Dual-lobe Henyey-Greenstein with configurable forward/backward lobes
• Approximate Mie (Jendersie & d'Eon, SIGGRAPH 2023) for clouds and fog
• Powder effect (Schneider & Vos 2015, Horizon Zero Dawn clouds)

Scattering

• Analytical multiple scattering (Wrenninge 2015) — zero extra rays
• Gradient-normal Lambertian blend for surface-like shading

Lighting

• Auto-detected directional and point lights from Nuke's Scene node
• HDRI environment maps via EnvironLight nodes
• L2 spherical harmonic environment lighting (10–20× faster for clouds)
• Virtual directional lights extracted from HDRI peaks
• ReSTIR weighted reservoir sampling for environment lighting
• Configurable sky/studio light rigs with presets

Shadows

• HDDA shadow rays (skips empty VDB tiles)
• Optional transmittance cache (precomputed per-light, 5–10× faster)
• Half/quarter resolution shadow cache options

Procedural Detail

• fBm Perlin noise overlay — adds micro-detail beyond VDB resolution
• Configurable scale, strength, octaves, roughness

VDB Support

• Density, temperature, flame, velocity, and colour grids
• Auto-sequence detection for numbered VDB files
• Dual VDB layer blending
• Point cloud rendering (PointDataGrid with splatting)
• Motion blur via velocity grid

AOV Outputs

• Density, emission, shadow, depth, motion vectors
• Per-light contribution (up to 4 lights)
• Albedo and normal passes (for downstream denoisers)

Viewport

• Interactive 3D bounding box and point cloud preview
• Viewport lighting preview
• Configurable point density and size

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Requirements

• Nuke 17.0v1 or later
• Windows x64 (upstream) or Linux x64 (this fork — RHEL 9 family verified, see LINUX_BUILD.md)
• OpenVDB (via vcpkg on Windows; Nuke's bundled OpenVDB on Linux)

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☕ Support This Work

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Building from Source

Prerequisites

# Install vcpkg dependencies
vcpkg install openvdb:x64-windows

Build (Windows)

cmake -B build -DNUKE_ROOT="C:/Program Files/Nuke17.0v1" -DCMAKE_TOOLCHAIN_FILE=C:/vcpkg/scripts/buildsystems/vcpkg.cmake
cmake --build build --config Release

Build (Linux)

./build_linux.sh   # see LINUX_BUILD.md

Package for Distribution

cmake --build build --config Release --target dist

Creates dist/VDBRender_v3/ ready to zip and share.

Optional: NeuralVDB Support

Neural compressed volumes (10–100× smaller .nvdb files):

cmake -B build -DNUKE_ROOT="C:/Program Files/Nuke17.0v1" -DCMAKE_TOOLCHAIN_FILE=C:/vcpkg/scripts/buildsystems/vcpkg.cmake -DVDBRENDER_NEURAL=ON -DLIBTORCH_PATH=C:/libtorch
cmake --build build --config Release

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Installation

1. Copy the VDBRender_v3 folder to %USERPROFILE%\.nuke\plugins\ and rename it to VDBRender

   Your layout should be:

   %USERPROFILE%\.nuke\plugins\VDBRender\nuke17\VDBRender.dll
   %USERPROFILE%\.nuke\plugins\VDBRender\nuke17\init.py
   %USERPROFILE%\.nuke\plugins\VDBRender\nuke17\menu.py
   %USERPROFILE%\.nuke\plugins\VDBRender\nuke17\lib\openvdb.dll
   %USERPROFILE%\.nuke\plugins\VDBRender\nuke17\lib\tbb12.dll
   ...
   

2. Add this line to %USERPROFILE%\.nuke\init.py (create the file if it doesn't exist):

   nuke.pluginAddPath('./plugins/VDBRender/nuke17')

3. Restart Nuke. VDBRender appears in the VDB menu.

Note: Runtime DLLs live in lib/ so Nuke doesn't try to load them as plugins. Do not move them into the parent folder.

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Usage

1. Create a VDBRender node from the VDB menu
2. Connect a Camera to input 1
3. Connect a Scene node (with lights and optionally an Axis for volume transform) to input 2
4. Set the VDB File path and click Discover Grids
5. Choose a Scene Preset or configure shading manually

Tips

• Clouds: Enable Shadow Cache (Quality tab) and set Env Mode to "SH + Virtual Lights" (Lighting tab) for 10–20× faster rendering
• Fire/Explosions: Use the Explosion colour scheme — it evaluates emission before density for fire-first ordering
• Sequences: Enable "Auto Sequence" to convert numbered filenames to #### padding automatically
• Performance: Start with a lower Quality value and Proxy mode for fast iteration, then increase for final renders

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Inputs

Input	Label	Description
0	bg	Background plate (sets output resolution)
1	cam	Camera
2	scn	Scene (lights, EnvironLight for HDRI, Axis for volume transform)

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References

• Wrenninge, M. (2015). Art-Directable Multiple Volumetric Scattering
• Schneider, A. & Vos, N. (2015). The Real-Time Volumetric Cloudscapes of Horizon Zero Dawn
• Jendersie, J. & d'Eon, E. (2023). An Approximate Mie Scattering Function for Fog and Cloud Rendering. SIGGRAPH 2023
• Kang, B. et al. (2002). Design of Advanced Color Temperature Control System for HDTV Applications

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License

See THIRD_PARTY_LICENSES.txt for third-party library licenses.