Region Lock

Selective Regeneration with Anchored Parts

Pin the parts you like, regenerate the rest. Locked regions stay frozen across iterations while the AI varies only what is free — no more starting over to keep one good thing.

Framing

The problem

Regenerating output destroys the parts the user already approved.

The pattern

Let users lock specific regions so AI only varies the unlocked rest.

Why chat breaks here

Chat regenerations are all-or-nothing — there is no surface for partial preservation.

Risks

Over-locking can trap users in local optima or hide better global alternatives.

Avoid when

The composition is so coupled that varying one part requires varying others.

Use when

Iteration is composite — some parts settled, others still being explored — and full regenerations destroy progress.

DOPE evaluation

Directability
Toggle locks at any granularity — region, paragraph, layer
Observability
Locked regions are visually marked across every iteration
Predictability
Locks guarantee the same content survives across regenerations
Explainability
Each lock carries a label naming what is preserved and why

In the wild

  • Midjourney Vary Region (Midjourney) — Editor with freehand/rectangular selection + prompt remix — locked regions stay frozen across iterations while the unlocked area regenerates.
  • Photoshop Generative Fill (Adobe) — 2026 release adds reference-photo-aware fills via Firefly 4, Gemini 3 Nano Banana Pro, and FLUX.2 Pro. Selection-then-fill remains the core gesture; the rest of the image stays untouched.
  • Ideogram · Canvas Magic Fill (Ideogram) — Mask a region on the canvas, adjust the generation window, prompt just that area — unaffected pixels stay locked while only the masked region regenerates.

FAQ

When should I use the Region Lock pattern?

Iteration is composite — some parts settled, others still being explored — and full regenerations destroy progress.

When should I avoid the Region Lock pattern?

The composition is so coupled that varying one part requires varying others.

What problem does Region Lock solve?

Regenerating output destroys the parts the user already approved.

Why is chat the wrong fit for this?

Chat regenerations are all-or-nothing — there is no surface for partial preservation.

Related patterns

  • Often paired with: Parallel Alternatives — Lock the keepers; let three candidates diverge only where it is unlocked.
  • Often paired with: Visual Intent Expression — Carry the look forward across iterations by locking the parts that match it.
  • Alternative to: Editable Plan — Pin parts of an output vs edit the steps that will produce the next output.

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