SaveStructure

Build it once. Save it. Build it again.

SaveStructure lets you select building pieces with your Hammer, name the structure, and rebuild it from the Hammer menu. Build the whole layout at once, or place a local hologram and construct it one piece at a time.

Features

• Select individual pieces with visible outlines; click again to deselect.
• Select a box covering multiple floors, then fine-tune the selection individually.
• Copy supported buildable pieces from ruins and other players' buildings, subject to ward access.
• Save named structures and find them immediately in the Hammer menu.
• Use readable save filenames and automatic short suffixes when names clash.
• Delete saved blueprints or unfinished holograms in-game, with confirmation.
• Preview the whole structure, rotate it, and use its snap points for placement.
• Build the complete layout using its total material cost.
• Place a free hologram visible only to you, then build each piece using its full material cost.
• Resume unfinished holograms after reconnecting to the same world with the same character.
• Toggle placement overlap checks and configure every mod shortcut, including modifiers and mouse buttons.
• Keep your saved structures across restarts and use them in other worlds.
• Rebuild ordinary pieces that can be repaired and dismantled normally.

Requirements and installation

Built against Valheim 1.0.16, with BepInExPack Valheim 5.4.2350. Jötunn is not required.

With a mod manager: install SaveStructure and its listed dependency, then launch your modded profile.

Manual installation: close Valheim and extract the package into BepInEx/plugins/SaveStructure/ in your active installation or mod profile. SaveStructure.dll should sit directly inside that folder. Launch the game through that profile.

How to save a structure

1. Equip your Hammer and press F8 to enter save mode.
2. Aim at a supported Hammer piece and left-click to select it. A mint outline marks selected pieces. Click a selected piece again to remove it from the selection. Buildable ruin pieces and other players' pieces are eligible; protected wards still restrict access.
3. Select the rest of the pieces you want to save. Start with a foundation or floor piece: the first selected piece defines the placement anchor and facing.
4. Press F7, enter a name, and confirm the dialog. The Hammer entry uses your chosen name. If it already exists, a short suffix is added automatically, for example Cabin [a3f91c].

Normal hammer placement, repair and removal are blocked while save mode is active.

For box selection, hold Left Shift and right-click while in save mode. Click a lower corner of the area, aim at the opposite corner, then click again to confirm. Scroll up / down to increase / decrease the height above the corners. While in box-selection mode, scrolling adjusts height without also zooming the camera or rotating a piece. The box includes pieces whose placement pivots fall inside it. Check the highlighted candidates before confirming; over-limit boxes are rejected without partially selecting them.

Additional boxes add to your selection. Left Shift + right-click again to add or remove individual pieces. If the selection was empty, the lowest piece nearest the first box corner becomes the anchor. If you select a piece individually first, that anchor is retained.

The selection and placement mode shortcuts are separate config options and can use different bindings. Plain right-click still opens the Hammer build menu outside save mode. All shortcuts above are configurable. Outside their relevant modes they have no effect; typing in chat, naming dialogs, menus and build-menu search blocks mod input. Positioning, rotating and placing a structure continue to use your normal Valheim Hammer controls.

How to build a saved structure

1. Open the Hammer build menu and search for your saved name. Entries use that name directly, without a Structure: prefix.
2. Select the structure to show its full preview. Menu entries use the Building tag and the first piece's icon.
3. Position and rotate it with the normal Hammer controls. Native snap points work; use alternate placement for free positioning.
4. Check the hint says WHOLE STRUCTURE (Left Shift + right-click to switch), then click to build it.

The description lists the total materials. In normal survival play, all materials must be in your inventory. The full cost is consumed once after construction succeeds, along with one Hammer action's stamina and durability. World free-build settings and native no-cost mode follow the normal Hammer behaviour.

Relevant crafting stations must cover the pieces being built. A station included in the saved structure can provide that coverage. Recipes and required DLC must be available. Wards, no-build areas and other placement restrictions are checked before construction.

How to build with holograms

1. Select a saved structure in the Hammer menu and use Left Shift + right-click until the hint says HOLOGRAM.
2. Position and rotate it, then place it normally. Placing the plan consumes no materials.
3. Keep your Hammer equipped, approach a hologram piece, and aim at it. The hint shows the material counts in your inventory against the full cost of that piece.
4. Press E to build it. All of that piece's materials must be available; there are no partial deposits. A successful build consumes that piece's cost once and uses Hammer stamina and durability.
5. Gather more materials and continue. Start with foundations and supporting pieces: holograms do not provide structural support. A hologram workbench must be built before it can provide crafting coverage.

Holograms are local visuals without physical collision. Other players and the server do not need SaveStructure to see completed vanilla pieces; unfinished plans are visible and usable only on your client. Original mods providing non-vanilla pieces remain necessary as usual.

Plans resume for the same world and character. Each hologram inherits its blueprint's name. Placing another plan with the same name adds a short suffix so the plans can be distinguished, without changing the blueprint's name.

Left Shift + Delete, while aiming at a plan, asks to remove its unfinished hologram without demolishing completed pieces. If an identical real piece already occupies a target position, pressing E clears that hologram piece without charging again. Completed pieces that are later destroyed are not automatically rebuilt.

Deleting saved builds

To delete a saved blueprint, select it in the Hammer menu and close the menu so its placement preview is showing. Press Delete, then confirm the named blueprint in the dialog. It disappears from your saved files and Hammer menu immediately. Existing holograms keep their own snapshots and remain usable; completed structures remain in the world.

To remove an unfinished hologram, equip the Hammer, aim at one of its remaining pieces, press Left Shift + Delete, then confirm. Its local plan and unfinished visuals are removed. Its saved blueprint and completed building pieces remain.

Choose No or press Escape to cancel either dialog. The two removal shortcuts are independently configurable as DeleteSavedStructure and RemoveHologram. If you assign them the same shortcut while both targets are available, the aimed hologram takes priority. Ordinary Hammer pieces are unaffected by blueprint deletion.

Placement collision

[Building] DisableCollision = false enables normal SaveStructure overlap checks. Set it to true, or press F10 in a placement context, to bypass those checks. The hint displays Collision: ON/OFF and the key updates the saved configuration.

This affects whole builds, hologram placement and construction through holograms. It does not make completed pieces non-solid, flatten terrain, or bypass ward access, material requirements, crafting coverage or other non-collision building restrictions. Ordinary Hammer pieces are unaffected.

Configuration and saved files

After the first launch, edit BepInEx/config/Dyls123.SaveStructure.cfg or use your mod manager's config editor.

Version 1.0.0 automatically renames the previous dylan.valheim.savestructure.cfg file on launch and carries over your settings. If both filenames already exist, the new file takes priority and the old file is left untouched. Saved structures and hologram progress keep their existing locations.

Shortcuts accept values such as F9 + LeftControl or Mouse1 + LeftShift. Set a shortcut to None to disable it. Choose distinct bindings for actions used in the same context. Selection and placement can share a binding because they are active at different times, or you can configure each independently.

When upgrading from 0.2.0, the old default F9 mode switch changes to Left Shift + right-click, and the default Page Up/Down height keys become unbound. Custom bindings are preserved: a custom SwitchMode is copied into both new options, unless you have already set separate values. This migration happens once; later edits, including restoring F9 or Page Up/Down, remain in place. Existing single-key settings and saved structures remain compatible.

Dyls123.SaveStructure.cfg.example documents the settings; it is not loaded automatically.

Structures are saved as JSON files in BepInEx/config/SaveStructure/structures/. Filenames use your chosen name, for example Cabin.json. Names are compared without regard to capitalisation; a duplicate gets a short random suffix instead of replacing the first save. Characters that are unsafe in filenames are replaced, and long filenames are shortened as needed. The full display name remains in the JSON. A further filename suffix is added if two different names sanitize to the same filename.

Old ID-only filenames are renamed when loaded, while keeping their internal IDs, layouts and hologram progress. If a file cannot be renamed, it remains usable under its old filename and the reason is logged. Keep using the JSON's original internal ID when sharing or moving an existing save.

Hologram positions and progress are stored separately in BepInEx/config/SaveStructure/holograms/<world-id>/<character-id>/, also using readable names. Each plan contains its own name and blueprint snapshot. Back up this folder with your saves if you want to keep unfinished work. These are local plans, not shared multiplayer material stores; restoring older world/character saves does not rewind the local plan files.

You can copy these files between profiles to share structures. Rejoin your world to load added or removed files. Modded pieces require their original mods wherever the structure is used. Invalid files or missing piece prefabs are reported in BepInEx/LogOutput.log; other valid structures still load.

What is saved

The mod saves piece types, positions and rotations. New pieces belong to the player placing the structure and start with their prefab defaults.

Chest contents, sign text, portal destinations, fuel, production queues, item-stand contents, bed claims and damage are not copied.

Current limitations

• Pieces must be within 128 metres of the first selected anchor.
• Terrain tools, terrain-changing pieces, vehicles, rescaled pieces, loose items, multiple-network-object prefabs, and pieces with special water, cultivation or connection rules are not supported.
• Terrain is not flattened. Choose a suitable foundation site; normal support, weather damage and collapse rules apply.
• Whole-structure placement approximates some wall, ceiling and slope rules. A preview may be rejected when clicked if a check fails away from the anchor.
• Previews show prefab geometry, without saved door states, particles, lights or other dynamic effects.
• Keyboard and mouse are the primary controls. Mode switching uses the configured shortcuts; naming uses the game's text dialog.
• Saved structure files and hologram plans are local and are not automatically shared with other players. Multiplayer compatibility and interactions with other building or inventory mods have not been comprehensively tested.

Compatibility

Successful in-game use has been reported for 0.1.0 and 0.2.0. Version 1.0.0 builds against Valheim 1.0.16; automated core tests and isolated Unity runtime checks cover storage, geometry, config filename/settings migration, mode shortcuts, naming, catalog removal, native confirmation callbacks and patch installation. The updated controls and deletion flows still need an interactive in-game pass, and multiplayer compatibility has not been comprehensively tested. Already built structures use the original piece prefabs and do not require SaveStructure to remain installed; any mods providing those original pieces are still required.

Changelog

1.1.0

• Added compatibility support for free-camera building mods that use the native Hammer: use the Hammer's input state when a camera freezes character input, and respect extended Hammer reach for individual/box selection and hologram construction.
• Recheck hologram targets during the Hammer action so temporary camera reach takes effect immediately; keep local previews visible near the detached camera.
• Added chest-pulling mod support for hologram construction through native full-cost requirement checks and resource consumption. Whole-structure placement retains the same native material path, allowing mods that extend these methods to supply both building modes.
• Hologram hints show required costs without treating inventory-only counts as the total available from modded storage.

1.0.0

• Renamed the active configuration to Dyls123.SaveStructure.cfg, automatically moving the previous config and preserving its settings.

• An existing Dyls123.SaveStructure.cfg takes priority without overwriting either file.

• Kept the existing plugin identity, saved blueprints and hologram progress compatible.

• Renamed the packaged example configuration to Dyls123.SaveStructure.cfg.example.

• Saved structures use the chosen name directly in the Hammer menu, without a Structure: prefix.

• Structure and hologram JSON files use readable names. Short random suffixes resolve duplicate display names and filename collisions without overwriting saves.

• Existing ID-only filenames migrate on load while retaining internal IDs and hologram progress; a failed rename leaves the original file usable.

• Each hologram has its own persistent name inherited from its blueprint, with a short suffix when needed to distinguish repeated plans.

• Added configurable DeleteSavedStructure (Delete by default) to remove the saved blueprint selected for placement, with confirmation and immediate Hammer-menu cleanup.

• Hologram removal now asks for confirmation. Deletion preserves completed pieces; deleting a blueprint also preserves existing hologram snapshots.

• Blocked gameplay input while removal dialogs are open and briefly after closing, so a confirmation click cannot also place a build.

• Split selection and placement mode shortcuts into SwitchSelectionMode and SwitchPlacementMode, both defaulting to Left Shift + right-click and independently configurable. Plain right-click still opens the normal Hammer menu outside save mode.

• Added scroll-wheel box-height adjustment, with configurable enable/disable and step size. The wheel does not also rotate pieces or zoom the camera while adjusting a box.

• Made the old Page Up/Down bindings optional (unbound by default).

• Automatically migrates the exact previous F9/Page Up/Page Down defaults once, copying a customized former shared switch into both new options while preserving explicitly set separate bindings.

0.2.0

• Added client-only hologram plans with full-cost construction per piece and saved progress per world/character.
• Added box selection with adjustable height, candidate previews and individual selection cleanup.
• Allowed supported buildable ruin pieces and other players' building pieces to be selected; ward access still applies.
• Added DisableCollision and a configurable collision toggle for saved-structure placement checks.
• Added one contextual mode shortcut for individual/box selection and whole-build/hologram placement.
• Made all mod shortcuts configurable, including mouse buttons and modifier combinations. Existing shortcuts and blueprint files remain compatible.
• Added local hologram removal, material/progress hints, and duplicate-piece reconciliation without extra material charges.
• Shortened temporary save filenames to avoid avoidable Windows Mono path-length failures.

0.1.0

Initial release.

• Thunderstore package layout with root-level DLL, manifest, 256x256 icon, README, changelog and example configuration.
• Hammer save mode with multiple piece selection and visible outlines.
• Named, versioned JSON saves and automatic Hammer menu entries.
• Full structure previews, native rotation and snap points.
• Combined material requirements and immediate construction using original network prefabs.
• Placement checks and rollback of failed batches.
• Configurable controls, selection reach and size limits.
• Valheim 1.0.15 build references, automated core tests and manual acceptance checklist.