Native render engine
Lumasmith shows up in Cinema 4D’s renderer list. Prepare Render Queue exports the scene once on the main thread, so the render thread never calls Python — the crash that killed the first queue test.
shippingTechnical beta · CUDA 12.8 · Cinema 4D 2027
GPU path tracing, native in Cinema 4D.
Lumasmith is an independent CUDA path tracer that runs as a render engine inside Cinema 4D. Progressive and physically based, with NEE lighting, GGX materials and OIDN denoising — no export roundtrip, no second application.
3.57 s / frame · 1080p · 128 spp + OIDN
- 1080p · 128 spp + OIDN
- 3.57s/frame
- Queue soak
- 200/200
- Live viewer
- 60Hz
- Rigid object update
- 0.2ms
RTX 4090, Render Queue, 10/10 frames
frames, no crash · 89.6 ms/frame
16 ms global timer, 8 spp per frame
p95 apply, 26-tri scene · 13.8 ms at 10k tris
01 — Capabilities
What works today, and what doesn’t.
Every row is a feature that has been built and run on the current build. The notes are measurements, not intentions — including the rows that say not yet.
shipping
partial
prototype
not yet
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CUDA path tracerProgressive integrator, BVH median split, deterministic seeds.shipping
3.8 G samples/s on the PBR test scene; BVH 828 vs 128 Msamples/s brute force.
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NEE lightingArea lights, omni converted to area, directional sun.shipping
Directional Lambert test: 0.0002% error against the analytic result; shadows verified.
-
GGX metallic-roughnessSmith geometry, Schlick Fresnel, energy-conserving lobe.shipping
White metal reads 0.99965 where energy conservation asks for 1.0.
-
Glass & transmissionRefraction through interpolated normals, not faceted triangles.shipping
Spheres stay smooth at the silhouette; transmission comes from the C4D transparency channel.
-
Textures & triplanarAlbedo, tangent normal, roughness, metallic. UV per triangle.shipping
Native triplanar projection, so Redshift colour layers survive the trip from C4D.
-
OIDN denoiserIntel OpenImageDenoise on CUDA, with a CPU fallback.shipping
In live it only starts after 1 s of idle at 64 spp, so it doesn’t flicker while you move.
-
Live viewerCamera, rigid objects, materials and lights, driven by a 16 ms timer.shipping
Moving one area light changed 277,301 pixels with no scene reload.
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Render QueuePersistent render server; the scene is exported once, on the main thread.shipping
200/200 frame soak and a 10-frame 1080p run, plus cancel — no crash.
-
Cinema 4D material bridgeRedshift OpenPBR and Standard, node groups, Maxon Asset Browser.partial
On the 10-material test scene: 4 ready, 4 partial, 2 fallback. Procedural bakes are still manual.
-
CausticsCPU photon map pass for light through glass.prototype
Area lights only; directional lights don’t emit photons yet.
-
Pyro volumesVDB cache resampled into a 96³ grid, ray-marched with emission.prototype
Temperature drives a blackbody colour; volumetric NEE with 64 samples. Multiple scattering missing.
-
Motion blur & depth of fieldSubframe camera sampling in the animation tool.partial
Working outside the queue; not yet wired into the native render engine.
-
AOVs & multipassSeparate render passes for compositing.not yet
Only the AO pass, and only from the CLI.
-
Spot & IES lightsPhotometric profiles.not yet
Area, omni and directional only, in both live and queue.
-
Installer & licensingWhat turns a build into a product.not yet
Today it is a plugin folder you copy into Cinema 4D.
02 — The engine
Built as a renderer, wired as a plugin.
The kernel, the integrator, the C4D bridge and the live viewer are one codebase. There is no host renderer underneath.
Body-frame live viewer
8 samples per frame while the camera moves, on a 16 ms global timer. The viewer window is optional: the renderer can stay hidden and publish frames into the C4D dialog.
shippingLights and materials, live
Area, omni and directional lights stream over UDP. Materials send only the fields you changed, so a colour tweak doesn’t wipe a metallic map.
shippingMaterial Converter
Preflight every material as READY, PARTIAL, BAKE or ERROR, then build non-destructive converted copies with base colour, roughness and normals — with undo and an HTML report.
partialDenoise, not blur
OIDN runs on the GPU with a CPU fallback, and it only engages once you stop moving. The AO pass is applied after denoising, so it doesn’t get smeared away.
shippingPyro volumes
Cinema 4D writes the VDB cache, Lumasmith resamples density and temperature and ray-marches it — including through secondary rays, so fire lights the floor.
prototype03 — Frames
Out of the current build.
Straight from the renderer: no compositing, no retouching. Where a frame came from the Render Queue or the live viewer, the caption says so.
Single RTX 4090 · Windows 11 · CUDA 12.8 · frames as written by the renderer.
04 — Roadmap
From technical beta to something you can buy.
The order of work is deliberate: stability first, then textures and animation, then packaging.
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Now — closing the alpha
in progress Oct 2026Long 1080p queues and GPU memory behaviour, progress and ETA, the AO pass out of the queue rather than only from the CLI.
-
Next — textures & materials
thenMipmaps and trilinear filtering, texture transform, EXR/TGA/PSD support, lower VRAM per map. On the material side: automatic bake for the fallback cases, metallic maps into the converted materials, triplanar preserved on copies.
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Then — animation & volumetrics
afterMotion blur and depth of field inside the render engine, deformation and vertex streaming, adaptive sampling, temporal denoise. Volumes move from diagnostic to production: sparse grids, multiple scattering, fuel and soot.
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Beta — the product
TBDInstaller, final plugin ID, licence and EULA, documentation, demo scenes, crash reporting and support. No date promised until the queue is boring.
05 — Requirements
What the beta needs.
One machine configuration is verified end to end. Wider hardware support comes after the product work, not before.
The plugin is a folder copied into Cinema 4D. There is no installer yet, and no licence to agree to.
OSWindows 11 (verified on build 26200)
GPUNVIDIA RTX · CUDA 12.8 (verified on RTX 4090)
HostCinema 4D 2027
DenoiserOIDN on CUDA, CPU fallback
OutputPNG · PFM · OpenEXR · ACES
Not supportedmacOS · AMD · Intel Arc
06 — Questions
The short answers.
Is Lumasmith for sale?
No. It is a technical beta: no installer, no licence, no price. Builds go to a small number of testers, and testers are told before anything changes about that.
Does it replace Octane or Redshift in my pipeline?
It is an independent renderer, not a wrapper. It lives in Cinema 4D’s renderer list next to the others, chosen per scene, so you can keep both and compare the same job.
What happens to my Redshift materials?
OpenPBR and Standard materials are mapped, node groups are traversed, and Maxon Asset Browser textures are materialised. Procedural setups that cannot be resolved are marked BAKE and skipped — the converter does not invent values.
Does it render glass and caustics?
Yes. Transmission uses interpolated normals so glass stays smooth. Caustics come from a CPU photon map that currently only samples area lights.
Why do I have to run “Prepare Render Queue” first?
Because Cinema 4D runs render engines on a worker thread, and calling Python from there crashed the host. Preparing the scene once, on the main thread, is the fix. If geometry, materials, lights or environment change afterwards, prepare again.
Which GPUs and which Cinema 4D?
Windows 11 with an NVIDIA RTX card (CUDA 12.8), inside Cinema 4D 2027. macOS, AMD and Intel Arc are not supported in this beta.
07 — Test the build
Break it on a real scene.
Production scenes are what this beta needs most. Tell me your GPU and what you shoot; builds are shared by hand, with a changelog.
- Free during the beta
- Direct line to the developer
- Your scene names steer the roadmap