Three Path Trace Viewer

A path-traced render is expensive, and the worst way to discover your composition is wrong is after you've burned ten minutes on high-sample frames. WASThreePathTraceViewer exists to stop that: it traces the scene live on the node and keeps adding samples to the same picture, so the view starts noisy and cleans up in place while you watch. Nothing is touched, nothing is committed, and no image comes out of it - it's a viewfinder, not a render.

What it does

Wire it a Three App (the same THREE_APP your render node would take) and it starts accumulating samples into one canvas right on the node. Drag inside to orbit the camera, wheel to zoom, middle-drag or hold shift to pan. When you move the camera the picture starts over - which is exactly the point: you get a quick dirty pass for composition, and if you wait a beat it refines in front of you so you can sanity-check the light and materials too.

Because nothing is rendered on the server and nothing leaves this node, the "render" is free. It's the tool the pack expects you to use for finding the framing that WASThreePathTraceRender will then take seriously.

Inputs

There are no outputs at all - this node ends a branch. The inputs mirror the path-tracer knobs you care about while framing:

• max_samples - how far the accumulated picture will go before it stops cleaning up.
• bounces / transmissive_bounces - how deep light paths go, same meaning as on the render node.
• filter_glossy - settles the bright speckle in glossy reflections.
• tiles and texture_size - how the work is chunked and how big textures are downsampled to while tracing.

The honest caveats

Two things the node's own description warns you about. First, if the scene is animated, the animation is held still to begin with - a moving scene starts every frame over and never settles, so the picture stays grainy forever. You can tell it to play anyway, but you'll be staring at noise; this node is for still framing, not motion preview.

Second, the same path-tracer light rules as the render node apply: it only sees Three Environment, emissive materials and directional/point/spot lights. A scene lit purely by an ambient or hemisphere light shows up black here, which is a great early warning - catch it in the viewer rather than after a real render.

Install

WASThreePathTraceViewer ships with WAS Node Suite v3. Install through ComfyUI Manager (search WAS Node Suite v3) or:

cd ComfyUI/custom_nodes
git clone https://github.com/WASasquatch/was-node-suite-comfyui.git

Restart after. Requires ComfyUI 0.14.0+ and Python 3.10+. The pathtracer runs in your browser, so you need an open tab and a GPU that can keep up. If the node doesn't show up, check features.threejs in <ComfyUI user dir>/was-node-suite/config.yaml - it defaults on in current releases, but that key is what gates the whole Three family.