Paint by Ichimatsu

What "Ichimatsu" means here

Ichimatsu (市松) is the Japanese name for a checkerboard pattern, and that's exactly what Paint by Ichimatsu draws into your masked region. It's the sibling of Paint by Single Color in the same pack: same no-model tensor math, but instead of one flat color it fills the mask with a two-tone checkerboard. No model, no download, runs instantly.

The inputs

• image, mask - the targets. A mismatched mask gets resized to the image (bilinear).
• Two colors for the checker: red1/green1/blue1 (default 255,255,255 - white) and red2/green2/blue2 (default 192,192,192 - light grey), each 0–255.
• size_x, size_y - the checker tile size in pixels, both defaulting to 16 (range 1–1024).

Output is a single IMAGE with the checkerboard inside the mask.

Why a checkerboard?

It serves the same pre-fill purpose as a flat color in SingleColor: overwrite the masked area with a pattern the inpaint can't ignore, so the model is forced to generate fresh content there instead of blending in the old pixels. The checkerboard adds two things over the flat fill. First, the masked region is unmistakable at a glance - that makes it a great mask-debugging tool, since you can see exactly what a node upstream selected. Second, the tile grid gives you a rough sense of the region's proportions before you commit an expensive pass to it. The "overwrite the mask with something flat so the model has to invent" trick is straight out of the masked-inpainting playbook; this is just the most visible version of it.

The caveat

Like its sibling, this is not a paint-by-example node. It doesn't touch the model, doesn't trigger the pack's multi-gigabyte download, and the README - which still claims the pack has 3 nodes - doesn't mention it at all. The source is a straightforward tensor op, so there's nothing hidden in it. If you only want the pack's actual exemplar inpainting, ignore this one. If you're building a masked pipeline and want a free visual placeholder, it costs nothing.

Install

ComfyUI Manager, search "paint-by-example", or:

cd ComfyUI/custom_nodes
git clone https://github.com/phyblas/paint-by-example_comfyui

Restart ComfyUI and it's there. No model download for this node - only the three paint-by-example nodes pull the Fantasy-Studio checkpoint on first run.