Storyboard Grid Generator

Before you generate a single storyboard panel, this node draws you the board. StoryboardGridGenerator takes a canvas size and a panel count and returns a clean template image: dark panel cells separated by bright borders. It's from domg73's ComfyUI-Storyboard-Tools pack, built for multi-panel Diffusion Transformer work where the whole trick is keeping frames symmetrical so content doesn't bleed across panel boundaries.

Why would you want a blank grid as an image? Because when you're working with a model like Krea2, you don't get per-panel control for free - a shared latent canvas tends to let details from one frame leak into its neighbors, and the author's whole workflow is about fighting that. A consistent template image gives you a structural reference to composite panels back into, to guide inpainting, or to use as a spatial reference so every frame lands in the same place. It won't fix the model for you (nobody's node does that), but it's the scaffolding the rest of the pipeline hangs on.

How it works

The node computes a layout from your panel count and renders a float tensor directly:

• auto - the smart mode: 1 panel → 1x1, 2 → 2x1, 3–4 → 2x2, 5–6 → 3x2, 7–8 → 4x2, 9 → 3x3, 10+ → 4x3.
• vertical_list - one column, all panels stacked.
• horizontal_row - all panels in a single row.
• custom - your own custom_columns × custom_rows.

Each active cell is filled with background_gray_value (default 25, i.e. near-black) while borders stay bright, then optional invert_colors flips the whole thing. There's no sampling, no VAE, no neural anything - it's a pure canvas renderer, fast and deterministic.

The inputs that matter

• width / height - canvas size, defaults 2048x1152 (the 16:9-ish ratio the author's Krea2 workflow uses).
• num_panels - how many cells to draw, 1–30. Default 4.
• layout_mode - auto is right 90% of the time; reach for vertical_list or horizontal_row for comic-strip layouts.
• transparent_cells - outputs an RGBA image with borders opaque and cells transparent, handy as an overlay. Note the 4-channel gotcha below.
• border_thickness / background_gray_value / invert_colors - cosmetic; fiddle when the default look doesn't fit.

The single output is an IMAGE, the rendered board.

Install

The pack is a five-file, torch-only affair - no requirements.txt, no model downloads, nothing heavy to babysit. Install with ComfyUI Manager by searching ComfyUI-Storyboard-Tools, or:

cd ComfyUI/custom_nodes
git clone https://github.com/domg73/ComfyUI-Storyboard-Tools

Restart and it shows up under utils/storyboard.

Gotchas

Auto layout only fills the exact cells it needs, and that bit people: with 7 panels you get a 4x2 board with one bright, empty hole. Counts that tile cleanly - 4, 6, 9 - give you a fully-framed board, which is exactly why the author's examples stick to 4 and 6 panels (their own testing says 8+ panels is where Krea2 starts falling apart regardless). And if you enable transparent_cells, you're emitting RGBA: some downstream nodes assume RGB and will misbehave, so either set it off or convert before it hits anything picky. It's a brand-new pack (single commit, July 2026) - treat the rough edges as part of the deal.