ComfyUI-EdgePainter

Edge Painter for ComfyUI

Draw guide strokes over an image with the built-in MaskEditor, and get the strokes out as a clean layer.

Edge Painter is a Load Image node with extra outputs. Right click it, choose Open in MaskEditor, and paint. Whatever you paint comes out separately as white lines on black, ready for Canny, Lineart or Scribble ControlNets. It also works as a mask or an overlay.

It changes nothing else: your normal Load Image and MaskEditor keep working exactly as before.

Why

• The MaskEditor is already a good brush tool, but it is set up for masks: a big soft brush, a dark overlay, and the result mixed into the image's alpha.
• For guide lines you want a thin, hard, white brush and the strokes as their own image. Edge Painter gives you exactly that, with no new canvas to learn.

Features

• Stroke profile, only for this node. When the MaskEditor is opened from an Edge Painter node, it switches to:

  • a white mask at full opacity;
  • a thin hard brush (3 px, opacity 1, step 2).

• Your settings are left alone. When you close the editor, your usual MaskEditor settings are restored. Brush changes you make inside Edge Painter are remembered separately for next time.

• White strokes in the node preview, instead of dark transparency.

• Optional mask input: the area you paint in. Connect your inpaint mask:

  • strokes outside it are discarded from every output;
  • if the mask comes from a painted Load Image, everything outside the area is dimmed (translucent, so you still see the photo) both in the node preview and inside the MaskEditor. The shading follows zoom and pan, and it is display-only: it is never saved into the image.
  • An empty mask is ignored.

• Built-in guide fusion. Connect the original guide (for example the Canny or Lineart of the same image) to the optional guide input, and choose fusion:

  • replace: inside the area, only your strokes. Use it to change a shape, such as a skirt, an arm or a road.
  • add: inside the area, the original guide plus your strokes. Use it to add details while keeping the shape: embroidery, prints, seams, patterns.

  The guide is resized to the image automatically, because preprocessors return their own resolution.

• Five outputs:

  | Output | Content | |---|---| | image | the loaded image, untouched | | strokes | only your strokes, white on black | | strokes_mask | your strokes as a MASK | | overlay | the image with your strokes burned in white | | fused_guide | the guide outside the area, and inside it replace or add (equals strokes without a guide input) |

• No dependencies, and nothing is patched globally. The node is plain Python, plus a small frontend script that only acts on Edge Painter nodes.

Edge Pencil: retouch a guide in black and white

The quickest fix for a guide: take the Canny (or Lineart, HED, depth...) of your photo at its original size, and touch it up by hand.

1. Connect the preprocessor output to guide, and the photo to size_like (preprocessors return their own resolution; this puts the guide back to the exact size of the photo).
2. Run once. The node shows the guide.
3. Right click, Open in MaskEditor. It opens on the paint brush, white and thin:
   • white adds lines;
   • press X to switch to black and erase lines (X again goes back to white);
   • white and black keep their own brush size (black starts at 12 px, to cover quickly).
4. Save, and run again: the guide output is your retouched guide. edited_mask marks where you painted.

If the incoming guide changes (a new photo, new thresholds), the node starts over from the new guide. The restart from guide button drops your retouches on purpose. As with Edge Painter, your normal MaskEditor settings are restored when you close the editor.

example_workflows/edge_pencil_basic.json: Load Image → Canny → Edge Pencil → preview.

Typical uses

• Guided inpainting: draw the edges of a road, a river or a wall with Edge Painter. Merge them with the Canny of the original photo inside your inpaint mask, then feed the result to a Canny ControlNet. The new content follows your lines and blends with the rest of the photo.
• Scribble / Lineart ControlNet straight from a sketch over a reference photo.
• Quick masks made of thin lines, such as cracks, wires or hair strands.

Install

• ComfyUI-Manager: search for "Edge Painter", once it is published.
• Manually:

  cd ComfyUI/custom_nodes
  git clone https://github.com/JacPointLab/ComfyUI-EdgePainter
  

  Then restart ComfyUI.

Requirements: a ComfyUI frontend that has the Vue MaskEditor (2025 or later). On older frontends the node still works as a Load Image with stroke outputs, but the automatic stroke profile is skipped.

Example

• example_workflows/edge_painter_basic.json loads an image, and previews the strokes and the overlay.
• example_workflows/edge_pencil_basic.json retouches a Canny in black and white.

License

MIT

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Español

Es un Load Image con salidas extra. Clic derecho → Open in MaskEditor y dibuja: lo pintado sale aparte, en blanco sobre negro, listo para ControlNet Canny, Lineart o Scribble. También sale como máscara (strokes_mask) y sobre la imagen (overlay).

Entrada opcional mask: la zona donde se pinta (tu máscara de inpaint). Los trazos fuera de ella se descartan, y lo que queda fuera se oscurece, de forma translúcida, en la vista del nodo y dentro del MaskEditor. Es solo visual y no se guarda.

Entrada opcional guide (la guía original, por ejemplo el Canny de la foto) y selector fusion:

• replace: dentro de la zona solo tus trazos, para cambiar una forma.
• add: dentro de la zona, la guía original más tus trazos, para agregar detalles como bordados o estampados.

La salida fused_guide va directo al ControlNet.

Solo al abrir el editor desde Edge Painter se activa el perfil de trazos: pincel fino y duro, y máscara blanca opaca. Al cerrarlo, tu MaskEditor normal vuelve a tus ajustes, y el pincel de Edge Painter se recuerda por separado.

Edge Pencil (retocar una guía en blanco y negro)

Conecta el Canny (u otra guía) a guide y la foto a size_like, para que la guía quede al tamaño exacto de la foto. Run una vez, clic derecho → Open in MaskEditor:

• blanco agrega líneas;
• X cambia a negro para borrar líneas;
• cada color recuerda su grosor.

Guarda y vuelve a ejecutar: la salida guide es tu guía retocada. Si cambia la guía de entrada, el nodo empieza de nuevo; el botón restart from guide descarta los retoques.