Regional Edit lets you change one part of a render instead of the whole thing: paint the area you want reworked, then Generate — only the masked region changes, and it blends back into the original.

When to use

You like a render but want to fix or restyle a single element — a facade, a window, a piece of furniture, the sky.
You want to remove an object and let the AI fill the gap to match its surroundings.
You want to apply a reference’s material or mood to just one area, leaving everything else untouched.

This is different from a layer mask, which non-destructively hides or reveals parts of a layer for compositing. Regional Edit regenerates pixels and bakes the result into a new layer; a layer mask never changes the underlying image. For layer masks, see Layer masks.

Paint a region and regenerate

Select a single image layer on the canvas.
Click the Edit image regions button on the prompt bar (the dashed square-with-cursor icon). A Regional Edit toolbar appears, docked above the prompt bar with a green outline.
Paint the area you want to change with any mask tool (see below). The painted region shows as an amber overlay.
Optionally type a prompt describing the change. You can leave it blank — a blank prompt defaults to removing the marked object, or to a reference-led edit when you have a reference attached.
Click Generate. Only the masked area is rendered; the result arrives as a new layer so your original stays intact.

Regional Edit works with the image models in the picker — Seedream, FLUX, Nano Banana, and GPT Image 2. It is not available for video layers. Each generation costs credits like any render — see Plans & Credits.

Regional Edit belongs to one image at a time. If you zoom to a different image — by double-clicking its thumbnail in the Layers panel, or with the Previous/Next image buttons — the mode closes and a Regional Edit Mode deactivated toast confirms it. Your painted region is kept, so returning to that image and re-entering Regional Edit picks up where you left off. Re-centring the image you’re already painting doesn’t close anything.

Mask tools

The Regional Edit toolbar gives you several ways to mark the region:

Brush — paint freely. A size slider sets the brush diameter; the Arrow Up / Down keys nudge it by one.
Freehand lasso — drag a loose outline; the shape closes into a filled selection.
Polygon lasso — click point-to-point for straight-edged selections.
Rectangle selection — drag a clean rectangular region.
Segment selection — appears when the layer has a colour map. Click an element and its exact shape is selected; hovering highlights the element under your cursor. Revit imports arrive with a map, and you can upload one to any other image.

Every painting tool has two modes: Add (grow the selection) and Subtract (carve it back). Press X to toggle between them.

For AI-assisted selection on any image, Smart Select (SAM) — click an object and the AI traces its shape for you, no drawing required — is part of the layer-mask editing tools rather than the Regional Edit toolbar. See Layer masks.

Refine the mask

Invert — swap masked and unmasked areas.
Clear — wipe the selection and start over.
Undo / Redo — step back and forward through your strokes (Ctrl+Z / Ctrl+Shift+Z).
Copy / paste a mask between layers — from the sidebar, copy one layer’s mask and paste it onto another; it adapts to fit the target layer. (This applies to persistent layer masks, not the Regional Edit selection.)

Masks are painted at the image’s native pixel resolution, so a brush “size 1” equals one real pixel of the source image, and that precision survives any layer resize — the mask never softens or drifts when you scale the layer.

How the edit blends back

Regional Edit always sends the full image to the model, then keeps only your painted region in the result. Around that region it adds a small, feathered safety margin so the new pixels merge seamlessly — shadows, reflections, and edges blend rather than showing a hard seam. It also colour-matches the rendered patch to the surrounding pixels, so the edit doesn’t drift in tone. Because the region is enforced after rendering, the rest of your image is guaranteed to stay exactly as it was.

Tips

Paint a little past the edges of what you want changed. The feathered margin needs room to blend, and a too-tight selection can leave a visible border.
A small region on a very large image renders at reduced detail — INTERSTITIAL warns you when this happens. Paint a larger area or upscale first if you need crisp results.
Removing something? Leave the prompt blank and paint over the object — the AI fills the gap to match its surroundings.
Use Subtract to trim overspray rather than clearing and restarting.

Layer masks — layer masks and Smart Select for non-destructive compositing.
Colour maps — what makes click-to-select work, and how to add one.
Generation & Models — pick the model that renders your edit.
Plans & Credits — what each generation costs.