Navigator above the Layers panel

[Fvzion]

The problem today

Zoomed in on a large image, there's no overview of where you are or quick way to jump elsewhere: you pan by hand, or zoom out and back in.

What changes for the user

A Navigator panel above Layers, as in Photoshop:

• the whole document in small, with a red box around what the canvas shows;
• click or drag in it to move the view there;
• zoom −/+ buttons and a slider from 1% to 3200%;
• it collapses from its header, its height is dragged from its bottom edge (it gives way so Layers keeps room), and View › Navigator hides it; all remembered.

How to try it

1. Open a large photo and zoom to 400%: the red box frames the visible part.
2. Drag in the Navigator: the canvas follows.
3. Paint a stroke: the picture updates a moment after the stroke ends.

In the code

• Rendering/NavigatorGeometry.swift: where the picture and the box go; centring the view clears "follow Fit", as any scroll does.
• Document/EditorSession+Navigator.swift: the picture is the same live composite the Magic Wand samples, so adjustments and masks show as on the canvas. It's drawn at the picture's own size (placing layers, not scaling the context), so a large document with adjustment layers stays quick.
• UI/NavigatorPanel.swift: redrawn a quarter second after edits settle, and only while open.
• NavigatorTests (11 tests), including a document over the surface limit with an adjustment layer.

Can be trimmed

View › Navigator can go; the panel's header still collapses it.

Tested on macOS 26.6 (Apple silicon): the full test suite passes. Not yet tried on macOS 27.

🤖 Generated with Claude Code