VDB_RENDER(1)

💖 vdb_render(1) — like, the user-commands era 💖

okay bestie, welcome to vdb_render(1), the manual page that ray-traces OpenVDB volumes and honestly? she eats. let's get into it 🦋

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🌈 NAME 🌈

vdb_render — ray-traces OpenVDB volumes ✨

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🎀 SYNOPSIS 🎀

vdb_render in.vdb out.{ppm,exr,png} [options]

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💅 DESCRIPTION 💅

Which: ray-traces OpenVDB volumes. Options: yes, she has options, and we are going through every single one of them, no skips, no skimming, because that's the vibe 🫶

• -aperture F — perspective camera aperture in mm (default: 41.2)
• -camera S — camera type; either "persp[ective]" or "ortho[graphic]" (default: perspective)
• -compression S — EXR compression scheme; either "none" (uncompressed), "rle" or "zip" (default: zip)
• -cpus N — number of rendering threads, or 1 to disable threading, or 0 to use all available CPUs (default: 0)
• -far F — camera far plane depth (default: 3.4e+38)
• -focal F — perspective camera focal length in mm (default: 50)
• -fov F — perspective camera field of view in degrees (default: 44.8)
• -frame F — ortho camera frame width in world units (default: 1)
• -lookat X,Y,Z — rotate the camera to point to (X, Y, Z)
• -name S — name of the volume to be rendered (default: render the first floating-point volume found in in.vdb)
• -near F — camera near plane depth (default: 0.001)
• -res WxH — image dimensions in pixels (default: 1920x1080)
• -r X,Y,Z
• -rotate X,Y,Z — camera rotation in degrees (default: look at the center of the volume)
• -t X,Y,Z
• -translate X,Y,Z — camera translation
• -up X,Y,Z — vector that should point up after rotation with -lookat (default: [0, 1, 0])
• -v — verbose (print timing and diagnostics)
• -version — print version information and exit
• -h, -help — print this usage message and exit

🧊 Level set options 🧊

• -color S — name of a vec3s volume to be used to set material colors
• -isovalue F — isovalue in world units for level set ray intersection (default: 0)
• -samples N — number of samples (rays) per pixel (default: 1)
• -shader S — shader name; either "diffuse", "matte", "normal" or "position" (default: diffuse)

☁️ Dense volume options ☁️

• -absorb R,G,B — absorption coefficients (default: [0.1, 0.1, 0.1])
• -cutoff F — density and transmittance cutoff value (default: 0.005)
• -gain F — amount of scatter along the shadow ray (default: 0.2)
• -light X,Y,Z[,R,G,B] — light source direction and optional color (default: [0.3, 0.3, 0, 0.7, 0.7, 0.7])
• -scatter R,G,B — scattering coefficients (default: [1.5, 1.5, 1.5])
• -shadowstep F — step size in voxels for integration along the shadow ray (default: 3)
• -step F — step size in voxels for integration along the primary ray (default: 1)

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🌸 EXAMPLES 🌸

look at her go, two whole examples, iconic behavior honestly:

vdb_render crawler.vdb crawler.{ppm,exr,png} -shader diffuse -res 1920x1080 \

-focal 35 -samples 4 -translate 0,210.5,400 -compression rle -v

vdb_render bunny_cloud.vdb bunny_cloud.{ppm,exr,png} -res 1920x1080 \

-translate 0,0,110 -absorb 0.4,0.2,0.1 -gain 0.2 -v

⚠️ Warning ⚠️

This is not (and is not intended to be) a production-quality renderer. Use it for fast previewing or simply as a reference implementation for integration into existing ray tracers.

like bestie, read that again. she's a preview girlie, a reference implementation queen. do NOT put her in prod, that's not her moment 💀 she's here for fast previewing and for being the blueprint you drop into your existing ray tracers. periodt.

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👑 AUTHOR 👑

This manual page was written by Mathieu Malaterre <malat@debian.org> for the Debian GNU/Linux system (but may be used by others). we stan a documented manpage, fr fr 🫶

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and that's the whole thing, bestie — this page is vdb_render 10.0.1, dated August 2026, part of the VDB_RENDER(1) set. slay, go trace some volumes 💖✨🎀