How to update navmesh not automatically?

Hello, i have pretty huge landscape field (stream level) with nav-mesh bounds in it. It looks smth like this:

291150-field.png

Big big square is landscape, small - nav-mesh bounds. I devide it so that if i change something for example in A2 or in B3 fields - to generate nav meshes only in these fields, and not to wait until it will be full territory generation.

291151-fieldwitha2b3generated.png

So, i found if to uncheck “Update Navigation Automatically” in editor preferences - it stop this strange and chaotic “update-nav-mesh-for-all-territories-on-each-saving-or-loading-even-if-u-don’t-need-it-and-didn’t-ask-it”. But return to question - how to update navmesh NOT automatically? maby there is some button for it somewhere?:slight_smile:

How it was in another editor: i select navmesh bound, then i press button “generate”., and after few seconds - it’s a miracle, i got generated nav-meshes baked to landscape, for one cell, that i changed. Can UE4 make it same?

Edit: from rendering

k, looks like there is no so special buttons =
also i found “force rebuild on load” checkbox. It disabled, but all nav meshes anyway rebuilding on load…
Another funny thing: if UE generating nav-meshes and autosave enabled - after autosaving it start to generate from begin. Endless loop here =\

More fun: after i disabled autosave and get regenerate nav-meshes for all area - UE completely kill levels, also it not spawning player character and any blueprints.

And more fun: with some magical way any backup files disappeared from project/saved/backups… is it normal?

Ok I found the answer : Build → Build Path