3D_GeneratePreviewVideo

The whole point of texturing a mesh is to see it, ideally spinning so you can catch every seam and smudge before you call it done. 3D_GeneratePreviewVideo is the pack's built-in turntable: it renders your textured model from all 24 camera angles around it, stitches the frames into an mp4, and hands you the file path. It's the reward node - the one you wire up last and watch with mixed relief.

What it does

It renders the mesh from every view in the renderer's 24-position rotation at 1024×1024 per frame, then encodes those frames into an mp4 via imageio-ffmpeg and saves it to the Paint3D/ folder next to your obj. It even shades the still-unpainted areas with a neutral gray + normal-based shading so holes read as gray blobs rather than black voids. And it does one smart thing: if an albedo.png already exists in that folder, it loads it as the initial texture first - which is why the workflow runs this after 3D_SaveUVMapImage to preview the finished result, or earlier if you want to watch the state mid-pipeline.

Inputs

• mesh_model - the MESHMODEL you want to spin.
• file_name - a string, default render.mp4. It's just the base name; the file lands in the Paint3D/ output dir next to your obj, and .mp4 gets appended if you leave it off.

Output

One output: video, typed as STRING - and it is a string, the absolute path to the mp4, not a video file type. This catches people. You can't wire it into a normal video preview node that expects an actual video object; you feed the path into something like VHS's video loader to actually watch it, or just open the path yourself. The bundled workflow pairs it with VHS_LoadVideoPath.

Installing

Same install as the whole pack - Manager search "ComfyUI-Paint3D-Nodes", or:

cd ComfyUI/custom_nodes
git clone https://github.com/N3rd00d/ComfyUI-Paint3D-Nodes
pip install -r requirements.txt
pip install kaolin==0.15.0 -f https://nvidia-kaolin.s3.us-east-2.amazonaws.com/torch-2.1.0_cu121.html

The requirements file pulls in imageio and imageio-ffmpeg for the video encoding, so a fresh install has what it needs. Kaolin remains the dependency that'll bite if your torch version doesn't match - pin torch==2.1.0 + cu121 if the wheel complains.

Gotchas

Because the output is a file path rather than a video type, the most common "it's broken" is actually "I don't know how to look at it" - check the Paint3D/ folder next to your obj file for the mp4. If it renders but shows an unpainted gray model, you ran it before the texture passes (or before albedo.png exists) - that's expected, not a bug. And 24 renders at 1024² means it's not instant; it's a render, go make tea. There's no real community help for this pack, but this is the least likely node to need any.