Compare maps

Compare Maps lists what differs between the map you have open and a map file: which prefabs were added, removed and moved, where each terrain layer changed and by how much, which paths changed, and what differs in the data a server reads. Use it to see what you have changed since you saved, what an autosave still holds, or how two versions of a map differ.

Comparing changes nothing. It runs no edit, it does not mark the map as changed, and the History window is the same afterwards. The only file it writes is a report you ask for.

Open it from FILE > Compare With…. It is a window you can drag by its title bar and resize from its bottom-right corner; it opens where you left it, its ? opens this page, and the camera, the selection and the other panels keep working while it is open.

Choose what to compare with

The open map is always one side, as it stands now, with your unsaved edits. Choose the other side:

• BROWSE FOR A MAP… picks any map file.
• ON DISK uses the map’s own saved file, so the list is what you have changed since you saved. It is greyed out for a map you have not saved yet.
• NEWEST AUTOSAVE uses the newest autosave of this map. It is greyed out until there is one.

A bar shows how far the comparison has got, and CANCEL COMPARE stops it; the last finished comparison stays in the list. A map file that cannot be read is named with the reason, and nothing is listed.

In every line, added means it is on the open map and not in the file, and removed means it is in the file and not on the open map.

If you edit the map after a comparison, the window says the map has changed. Compare again to bring the list up to date. Opening another map clears the list.

Read the list

The top of the window has one line per part with its counts. Under it, each part folds open:

Part	What it lists
Prefab differences	Prefabs added, removed, moved, or left in place under another category.
Path differences	Roads, rivers, rails and power lines added, removed or changed.
Terrain differences	Each layer that differs: height, water, ground textures, biome, topology and holes.
Server data differences	Wiring, markers, volumes, loot, vending and NPC profiles, ziplines, monument names and Deep Sea settings.

Click a line to select its prefab. Double-click it, or press Enter, to select it and move the camera to it. A line with no prefab on the open map, such as a removed prefab, a terrain region or a path, moves the camera to the spot on a double click. Hover a line to read all of it.

Each part shows its first 300 lines. SAVE COMPARISON writes all of them.

Prefabs

A map file does not give a prefab a name of its own, so Creator matches prefabs by what they are and where they stand:

• A prefab at exactly the same place, rotation and scale on both sides is the same prefab and is not listed.
• A prefab of the same kind within the Move radius (m) of where one stood is that prefab, moved. One line gives how far it moved, how far it turned and how its scale changed. The radius is 25 m unless you change it; a larger radius reads more pairs as moves, a smaller one reads them as one removed and one added. It applies to the next comparison.
• Whatever is left is added or removed.

Lines are grouped so a large change stays readable:

• A monument is one line by its name, and a monument is matched at any distance, so one you dragged across the map is still one moved line.
• A custom prefab group is one line with the number of members that changed. A group you moved as a whole is one moved line, however far it went.
• Every other prefab is one line under its prefab folder.

Terrain

Each layer that differs has a line with its totals, then its largest regions, each with its size and where it is:

Layer	What counts as a difference
Height and Water	A cell that moved by more than the smallest step a map file can store, about 3 cm. The line gives the largest rise and fall in meters.
Ground textures and Biome	A cell where any texture or biome has a different strength. Each one counts its own cells, and the line says on how many cells the leading one changed.
Topology	For each topology, the cells that gained it and the cells that lost it.
Holes	Cells that became a hole (opened) or stopped being one (closed).

When the two maps are different sizes, or a layer has a different resolution, Creator reads the file at the open map’s positions and marks those numbers after resampling.

Server data

Creator’s own data is compared entry by entry: a wired prefab by what it is and where it stands, a marker or a volume by its kind and position, a profile or a spawn group by its name. A line says which settings differ.

Data written by another tool is compared as a whole. The line says whether it is on one side only, or on both with different contents, and gives its size. Its contents are never listed, and a map’s edit password is never read.

In the viewport

While the window is open, the viewport marks the prefab differences near the camera: a blue box where a prefab was added, a red box where one was removed, and an orange box where one moved to, with a line back to where it stood. The boxes are markers of a fixed size, not the prefab’s own outline. At most 2,000 are drawn, the nearest first, out to 1,500 m. Closing the window hides them.

On the ground

When a terrain layer differs, the window has a Shade on the ground list under the summary. Choose a layer and Creator shades the terrain where that layer differs, while the window is open:

• Height and Water: yellow to red where the open map is higher than the file, pale to deep blue where it is lower. The stronger the color, the larger the change; the line under the list gives the largest.
• Ground textures, Biome, Topology and Holes: pink wherever the layer differs.

One layer is shaded at a time, and Off removes it. The shading follows the ground as you sculpt, goes when you close the window, and is never saved with the map.

Save the comparison

SAVE COMPARISON writes two files into a folder you choose, one to read and one for a tool: <name>.compare.txt and <name>.compare.json. The dialog starts in Desktop\CreatorDiag\compare\. A report names each map by its file name only, never the folders it is in, so you can attach it to a bug report.

From the command line

Creator can compare two map files without opening either, and tell a script whether they differ:

Creator.exe -batchmode -mapcompare="C:\Maps\new.map|C:\Maps\old.map" -mapcompareout="C:\Maps\compare"

The two files go inside one pair of quotes with a | between them. Added is in the first file and not in the second. Creator writes compare.txt and compare.json into the folder -mapcompareout names, or into Desktop\CreatorDiag\compare\ when you leave it out, and then closes. It needs no Rust content for this, and it opens no window when you start it with -batchmode.

Exit code	Meaning
0	The two maps are the same.
1	The two maps differ. The two files say how.
3	The comparison could not run: a file could not be read, the two files were not given, or the report could not be written.

Ask your AI client

If you have connected an AI client (Claude Desktop or Claude Code), it can run the same comparison with the compare_map tool and go through the differences with you. It takes path (the map file to compare against), other (a second map file, when you want two files compared and not the open map) and limit (how many differences to return for each part, 25 when you say nothing). It changes nothing, so it needs no click.

It reads map files only from Creator’s own folders: your Creator maps folder, the folder of the map you have open, and the app’s data folder, where your autosaves are. For a file anywhere else, use BROWSE FOR A MAP… in the window. What the tool returns is what the window lists: your maps by file name, the game’s own prefab paths, and positions.

What is not compared

The editor’s companion file beside each map is not compared. Trigger volumes of the custom kind and the generation recipe live there. See the map file and the sidecar.