🌄 Krea2 Background Effect

Environments are the fiddliest part of prompting, and this node is a cheat code for them. Krea2 Background Effect ships 592 ready-made background descriptions - classrooms, rain-soaked streets, neon alleys, studio voids - each with a local thumbnail, and it appends the one you pick onto your prompt with a single click. It's the background-only sibling of Krea2 BBOX Prompt Effect, and if you're building the Krea2 BBOX pipeline, it's the easiest way to get a credible environment without hand-writing "dusty afternoon light in a converted warehouse" for the dozenth time.

Why it fits Krea 2 so well: the model is a natural-language model that rewards long, specific scene description - Krea's own prompting guidance is to describe the image the way you'd describe it to a person. A full environment paragraph in your background slot is exactly the kind of input it responds to. This node just keeps you from having to type it.

How it works

The 592 presets live in a bundled web/background_presets.json, with local WebP thumbnails next to them - no GitHub raw URLs, no CDN, no startup download. The node loads that JSON, and when enable_effect is on, it looks up the selected preset and appends its text to prompt_in on a new line. That's the whole mechanism, and it's deliberately separate from the BBOX JSON: the README points out that Background Effect appends a ready-made environment without changing your layout data, so you can swap backgrounds freely and re-render.

Everything's local. There's no model-specific dependency, no separate model download, and it works whether or not you're even using the rest of the suite - feed it any prompt string.

The inputs that matter

• prompt_in - the prompt to augment. In the standard pipeline that's Krea2 BBOX Export's prompt_text, but it'll happily take a raw string.
• preset - the background, defaulting to Classroom. This is where the 592-entry list lives.
• category - filters the preset list (default Background). There's also Custom for your own saved environments.
• mode - Preset (default) or Custom, which routes through the custom_preset text box instead.
• custom_preset - type your own environment description and use it directly.
• style_boost - an optional extra phrasing toggle; off by default.
• enable_effect - kill switch. Off, and it passes prompt_in through untouched.

Outputs

Two strings, same shape as the Prompt Effect node. prompt_out - the combined prompt, wire it into CLIP Text Encode. background_text - just the appended background fragment, so you can inspect it or reuse it elsewhere.

How to install it

Identical to the rest of the suite - one clone gets all five nodes, and this one is pure local data:

cd ComfyUI/custom_nodes
git clone https://github.com/ukr8b3g-cmyk/Krea2-BBOX-Prompter.git Krea2-BBOX-Prompter-Suite

Restart ComfyUI and hard-refresh (Ctrl + F5); the thumbnails are front-end assets, so a stale cache can leave the picker looking empty. ComfyUI Manager users search "Krea2 BBOX Prompter Suite." No dependencies, no downloads.

Where people get burned

The usual: it's additive, so a weak prompt_in is still weak after the background is appended - the background is an environment, not a scene. And don't expect Krea 2 to honor it like a mask; the suite's own README and community tests are consistent that bbox guidance isn't pixel-accurate, but background text lands reliably well. Also keep the two effect nodes straight: Krea2 Background Effect for environments, Krea2 BBOX Prompt Effect for photo/art/lighting/mood. Grab the wrong one and you'll spend a while wondering why your "sunlit street" preset output a film-grain tag.