Switch Latent Fallback 🐲

Latents are the trickiest type to switch in ComfyUI, because they're just dicts with samples tensors and hidden metadata - wire the wrong thing and the sampler errors in the middle of a run. Switch Latent Fallback is the typed variant of the pack's fallback switch, built for exactly one job: pick between two latent branches without crashing when one of them doesn't exist.

What it does

Same fallback logic as the family:

• boolean = True → output on_true_fb.
• boolean = False → try on_false; if it's None (bypassed, muted, disconnected), fall back to on_true_fb and log it.

The inputs are LATENT-typed, which is the point. Latent size mismatches are a classic silent failure - if your two branches produce different-sized latents, a switch won't save you (the downstream sampler will still reject a mismatched one), but at least the type check keeps you from wiring a conditioning or an image into a latent socket and discovering it three nodes later.

The scenario it's made for

The img2img vs txt2img pattern is the canonical use: one branch starts from a real image (encoded to latent), the other starts from an empty latent. Toggle between "generate from scratch" and "regenerate from this image" by flipping the boolean, and when you bypass the img2img branch entirely the switch just hands back the empty-latent path instead of erroring. That's the whole pitch, and it works.

Same logic applies to choosing between a KSampler's output latent and a VAE-encoded one, or between two candidate sampling branches in a comparison workflow.

Inputs and output

• boolean - which latent input has priority (default False).
• on_true_fb - the latent for True; also the fallback.
• on_false - the latent for False, if provided. Optional on purpose.
• Output: a single LATENT.

The fallback console message is informational. Silence it via the pack's settings if it gets chatty.

Installing it

cd ComfyUI/custom_nodes
git clone https://github.com/DraconicDragon/ComfyUI-RyuuNoodles

Restart ComfyUI, or use ComfyUI Manager (search "RyuuNoodles"). No models, no extra dependencies.

Gotchas

Latent switching has a hidden landmine that isn't the switch's fault: two latents may have different sizes, and ComfyUI's latent dicts carry samples, masks, and sometimes noise_mask entries. If you switch between latents of different resolutions, downstream nodes will happily tell you it's fine right up until the sampler throws a shape mismatch. This node selects the latent; it doesn't reconcile them. Keep your two branches on compatible sizes, or run them through the pack's Scale To Multiple nodes first - that combination is where this switch earns its keep.