ZeroClip-C Load Projection

ZeroClip-C is the variant that needs nothing to run - in its "pure" mode it just samples random points on the unit hypersphere. But it has a second mode, "guided", which uses a PCA projection to pull those random samples toward the manifold of real CLIP embeddings. ZeroClip-C Load Projection is the loader for that projection matrix. It's the one node in this pack you can safely skip, which makes it both the least important and the easiest to misunderstand.

The key thing to internalize: you do not need this node for ZeroClip-C to work. Pure mode requires zero artifacts, zero setup, zero downloads. Load Projection only matters if you pick guided in a ZeroClip-C Conditioning node - and if you pick guided without connecting a projection, the Conditioning node throws an error on purpose.

The input and output

• projection_file - a dropdown of .npz files in models/zeroclip/ (sample: projection.npz). It's the PCA projection matrix built by analyzing real CLIP embeddings.
• Output: projection (ZEROCLIP_C_PROJECTION), which feeds the optional projection socket on the C Conditioning nodes.

The file contains PCA components and a mean vector, and the guided sampler uses them to project an entropy sample onto the principal components of CLIP embedding space. The result is statistically closer to what a real text-encoded conditioning looks like - "near-language, semantically plausible" per the README - without being tied to any specific words.

Getting the projection file

From huggingface.co/mushroomfleet/zeroclip into models/zeroclip/, or build it: python build_artifacts.py --variant C --out ../../models/zeroclip/projection.npz (~2 minutes on CPU, needs transformers to generate the source embeddings). SDXL gets its own seq and pooled projection files.

Install

Part of ComfyUI-ZeroCLIP-nodes. ComfyUI Manager (search "ZeroCLIP"), or:

cd ComfyUI/custom_nodes
git clone https://github.com/MushroomFleet/ComfyUI-ZeroCLIP-nodes

Restart ComfyUI; it's under ZeroClip/C - Pure Entropy. No pip install at runtime.

Where people get burned

• Loading it, then running pure mode, and wondering why nothing changed. In pure mode the projection input is ignored by design. The tooltip on the C Conditioning node says exactly this. If you connected a projection and picked pure, it's a no-op - that's correct behavior.
• Guided mode with no projection connected. The opposite failure: mode is guided but there's no Load Projection upstream, and the node errors with "Guided mode requires a projection input. Connect a ZeroClipC_LoadProjection node or switch to 'pure' mode." Read that error as the pack telling you exactly what to do.
• Expecting it to be a "model." It's not a model you can prompt; it's a statistical crutch that keeps entropy samples near the CLIP manifold. Guided isn't "control," it's "less alien."