> For the complete documentation index, see [llms.txt](https://2yeet.gitbook.io/anvilcsg/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://2yeet.gitbook.io/anvilcsg/validation-and-build/check-map-and-recovery.md).

# Check Map and Recovery

**Check Map** finds common authoring problems before a build. Recovery snapshots provide a way back after a risky edit or interrupted operation.

## Running Check Map

Click **Check Map** in the top toolbar.

The summary reports:

* Brush, mesh, submesh, and triangle counts
* Visible, hidden, solid, and trigger counts
* Materials and mapper scripts
* Broken or unreconstructed geometry
* Warnings, UV risk, and GI issues

Issues are grouped into Rebuild, Materials, Trigger GI, Solid GI, Lightmap UV, and Other.

Select an issue to see its details. Depending on the problem, Check Map can offer actions such as:

* Select the source object
* Save the scene
* Rebuild a brush or terrain
* Refresh a decal
* Remove a missing script component
* Fix GI settings
* Regenerate UV2

The scan itself is read-only. Anvil changes the scene only after you choose a **Fix** action.

## Build-blocking problems

Anvil can stop a normal build when continuing would produce unreliable output. Examples include:

* An invalid or unsaved source scene
* An output path outside the Unity `Assets` folder
* A missing or invalid brush mesh
* A broken shader
* Invalid terrain data
* A decal that lost its target
* A missing mapper script
* Mapper-script data containing an unsupported object reference

Warnings can include a dirty scene, a missing material or texture, or an empty build scope. Read the issue text before using a fix.

If a full build is blocked, the Build Map window may offer an isolated incomplete preview. That preview can omit broken content and does not replace the last valid map.

## Creating a recovery snapshot

You can create a snapshot from:

* **File > Create Recovery Snapshot**
* **Tools > Anvil > Recovery**
* The Recovery section inside Check Map

Anvil also creates checkpoints for build operations and supported risky modeling or terrain operations. A dirty, saved Anvil scene can receive an automatic snapshot while you work.

The Recovery window provides:

* Create Snapshot Now
* Restore Last Good
* Restore an individual snapshot
* Delete an individual snapshot
* Open Folder

By default, Anvil keeps up to 12 snapshots for each scene.

## Restoring a snapshot

Before restoring an older snapshot, Anvil creates a new pre-restore checkpoint. The restore affects Anvil authoring roots and leaves unrelated scene objects and generated map output alone. The operation is grouped into one Unity Undo step.

Use **Restore Last Good** when you want the newest usable checkpoint. Open the full Recovery window when you need to inspect timestamps or choose an older snapshot.

## Where snapshots are stored

Snapshots are stored under the project's `Library/AnvilRecovery` folder.

This has two important consequences:

* Recovery snapshots are not included in source control.
* Deleting the `Library` folder removes them.

Recovery is a safety net, not a permanent backup. Keep normal scene files and the project under version control or another backup system.

## When Recovery is unavailable

Snapshots cannot be created or restored while Unity is:

* In Play Mode
* Compiling scripts
* Refreshing assets
* Baking lighting

An unsaved scene also cannot receive a durable recovery snapshot. Save a new scene before beginning substantial map work.