DA3_PreviewPointCloud

This node gives you an interactive 3D preview of a point cloud right inside ComfyUI - orbit it, spin it, check whether your depth reconstruction actually looks like the scene before you commit to exporting anything. It's the "did that work?" node. Point cloud workflows are fiddly enough that being able to eyeball the result in the graph, instead of round-tripping through Blender every time, saves you a lot of grief.

How it works

It loads a saved point cloud file and renders it in an interactive viewer embedded in the node. Notably, its input is a file_path string, not a live POINTCLOUD object - so it reads a .ply off disk rather than taking the cloud directly. In practice that means you point it at the file that DA3_SavePointCloud (or the Gaussian export) just wrote. The other input is color_mode (default RGB), which switches how points are tinted - RGB shows the real image colors, other modes can color by depth or by which view a point came from, which is handy when you're debugging multi-view fusion.

It's an output node with no outputs - it exists purely to draw the preview. Nothing wires out of it.

The one thing you need to know

Be honest with yourself about this node: it's the flakiest thing in the pack, and it's been that way since release. On the pack's launch thread, multiple people reported the exact same thing - the preview showed nothing, a blank viewer - while the .ply file saved perfectly fine. The author pushed fixes and at least one tester came back to confirm "with the last updates the Preview point cloud node works as intended," but others were still seeing blank previews after that. It's browser- and version-sensitive in a way the rest of the pack isn't.

So the practical stance: treat the preview as a nice-to-have, not the source of truth. Your actual deliverable is the saved .ply. If the preview is blank, your reconstruction is almost certainly fine - open the file in Blender or a .ply viewer to confirm. Don't spend an hour debugging your depth settings because a WebGL preview widget wouldn't paint.

If the preview is blank

A few things genuinely help:

• Update the pack. The fixes for this landed in updates after the first release. If you installed early, pull the latest.
• Try a different browser. This is a real fix people reported - the embedded 3D viewer behaves differently across Chrome/Firefox, and a hard refresh sometimes wakes it up.
• Confirm the file actually exists. This node reads a path. If file_path points at nothing - because the save node didn't run, or the path is wrong - there's nothing to draw. Check that DA3_SavePointCloud fired and produced a real file first.
• Sanity-check the cloud isn't empty. If your confidence_threshold was cranked too high upstream, you may have filtered away nearly every point. A cloud of twelve dots looks like a blank viewer.

Once you've confirmed the .ply opens elsewhere, stop worrying about the preview and move on - the export is what matters.