Synthetic neural rendering workbench

One asset. A fair comparison.

My earlier research showed where Gaussian splats reproduce materials well and where they fail. Neural Prism turns that finding into a controlled set of tools for testing the difference.

It renders an existing 3D asset, trains a neural scene and compares both results with the same cameras, lighting and colour pipeline.

Front three-quarter path-traced view of the Flight Helmet
FLIGHT HELMETMesh · path trace · splat · hybrid

Working prototype

Tested on Apple Silicon

Mojo + WebGPU

More hardware to validate

One controlled system

Controlled inputs make the comparison fair

Neural Prism keeps the asset, camera, lighting and colour pipeline fixed while the rendering method changes. A visible difference can then be traced to the method under test, rather than to an unnoticed pipeline change.

  1. 01

    Render

    Start with a glTF or GLB asset. Produce matched views, camera data and scene-linear EXR channels that become the reference for every later stage.

    Mojo Render
  2. 02

    Learn

    Train, evaluate and export Gaussian splats from the controlled capture. Error maps show where the learned scene differs from the reference.

    Mojo Splat
  3. 03

    Compare

    Inspect PBR, progressive path-traced, splat and hybrid output through one live camera. The shared view makes the trade-offs visible.

    WebGPU viewer

Browser renderer

Run the same comparison in the browser

The browser workbench uses Babylon.js Lite and custom WebGPU path-tracing shaders. One live camera moves between PBR, path-traced, splat and hybrid views.

The browser is therefore part of the experiment, not only a place to present the output. It lets the person inspecting the result see the same representation choices directly.

Runtime
WebGPU
Scene
Flight Helmet
Modes
PBR · path trace · splat · hybrid
WEBGPU WORKBENCH CAPTUREBabylon.js Lite · custom shaders

Progressive WebGPU path tracing

Follow the path tracer as the image converges

The sequence holds the Flight Helmet camera still and increases the samples per pixel from 8 to 256. This makes the reduction in Monte Carlo noise visible without changing the scene or framing.

The final pair compares the raw 256-sample image with its denoised result. The Dragon Attenuation image then shows the same process on a difficult transmissive material under a bright HDR environment.

Raw 8-sample WebGPU path trace of the Flight Helmet from the front
FLIGHT HELMET · RAW WEBGPU PATH TRACE8 SAMPLES / PIXEL

At eight samples, Monte Carlo noise obscures much of the material detail. The camera, scene and framing stay fixed across the sequence.

Evidence from earlier research

Reflective and transmissive materials show the limit

Gaussian splats render quickly, but speed is not enough for product visualisation. Third-order spherical harmonics provide limited directional information, and that limit is clearest in reflections and transmission.

AgX tone-mapped path-traced reference of the amber Dragon Attenuation model in a bright workshop HDR
PATH-TRACED REFERENCE128 spp · MIND · AgX
Front three-quarter Gaussian splat render of an amber transmissive dragon
RENDERED SPLATHeld-out view 71 · complete subject silhouette
Error map for the same amber dragon view
ERROR MAPSame camera · brighter areas contain more error

This held-out view keeps the full subject visible from the front and avoids the reverse of the checkerboard support, making the comparison easier to read.

WHY SPHERICAL HARMONICS MATTER

Traditional splats use low-order spherical harmonics to vary colour with view direction. This compact model suits many diffuse surfaces, but it cannot reproduce many sharp reflection or transmission lobes.

Prism measures those errors while testing richer directional models. It also tests hybrid results that retain triangles for materials a splat cannot represent well enough.

Why Mojo

Why I am building the system in Mojo

Graphics research often combines Python orchestration, C++ systems code and vendor-specific GPU kernels. Every boundary adds code to maintain and another place for an experiment to change before deployment.

Mojo provides high-level development and low-level control of CPU and GPU kernels in one language. In Prism, it covers path tracing, image processing, splat training and evaluation.

The aim is to reduce duplicated systems and make the research easier to move from a workstation to other accelerators and cloud hardware. That only matters if the same code remains correct on each target.

Neural Prism is in alpha and runs on Apple Silicon today. AMD, NVIDIA, Qualcomm and cloud support are planned, but they remain validation targets until the tests pass.

Learn more about Mojo

ONE CODEBASEMojorender · train · evaluate
TESTEDApple Silicon
PLANNEDAMD
PLANNEDNVIDIA
PLANNEDQualcomm
PLANNEDCloud

Next research

Observed failures define the next experiments

Each research direction starts with a failure in the earlier work. Prism supplies common captures, cameras and evaluation, so each proposed improvement can be tested against the same evidence.

R·01

Beyond SH3

Test richer directional colour models against the same held-out views. The goal is to improve sharp reflections and transmission without losing interactive performance.

R·02

Hybrid rendering

Use triangles or splats according to the material. This keeps the speed of a neural scene without requiring one method to represent every surface.

R·03

Adaptive views

Use measured error to select the next camera. Each new capture should add missing evidence, rather than another view without a clear reason.

R·04

Relighting

Separate the captured appearance from new lighting. A useful representation should preserve the asset while allowing the illumination to change.

Project summary

What Neural Prism is for

Neural Prism is not a one-click photogrammetry service. It is an open test harness for researchers and artists who need synthetic ground truth and controlled comparisons.

Its purpose is to establish where neural rendering is already useful, measure where it fails, and use that evidence to build better representations for interactive delivery.

Mojo Render and Mojo Splat project flyerOPEN THE PROJECT FLYER ↗