Change part of an image

Use a mask when the change should focus on a region of the source.

Before you start

A source image in Edit and a mask-compatible engine.

Steps

Open Edit and check Current source. Describe what should appear in the region, including material and light.
Open the mask painter and paint the area to change. Use erase or undo to correct the mask before saving it.
Save the mask changes, return to the editor and review the instruction. Saving a mask does not generate an image.
If Prompt is connected, edit the instruction in the connected Text, Assistant or List card. That input owns the instruction; a local draft does not override it.
Review the estimate and generate the edit. Compare the result with the source used, including the area outside the mask.

What you get: A new result to inspect, with the painted region guiding the edit.
What to keep in mind: A mask and Keep instructions do not guarantee unchanged geometry. Masks belong to their source: if the source changes or cannot be verified, repaint or remove the mask before running.

Architectural prompt examples

Anatomy of a strong prompt

Name the subject and geometry, then materials, light and camera. Give each sentence a clear purpose.

Two-storey timber house with a cantilevered upper volume. Warm larch cladding, black window frames. Golden hour, long soft shadows. Eye-level three-quarter view.

Iterate on your building

With an image connected to Edit, describe the change and what should stay. Inspect the result: a preservation instruction is not a guarantee.

Same house, same view. Swap the facade to weathered red brick.

Describe the masked result

Describe what should appear in the painted region, including material and light. Available mask controls depend on the engine.

Floor-to-ceiling glazing with slim bronze mullions

Address image slots

In Edit, image 1 is the source. Image 2 and later are references in the displayed order. Explain each image's role.

Place the building from image 1 into the red-marked area of image 2. Match perspective and scale.

Separate design and representation

A design style describes the architecture; watercolor or marker describes its representation. State which should change.

Describe film movement

Use camera verbs: orbit, push-in, rise and reveal. Choose an available duration. For 3D, use a clear view and inspect inferred surfaces.

Slow cinematic orbit around the building, dusk light

Populate with intent

Describe who uses the space, how busy it feels, and the light the figures should match.

A lively number of people: families with children, two cyclists. Late afternoon light.