v0.14.0 — get your ships in-game

A big update since v0.9.0, headlined by getting your designs into an actual playthrough no more hand-editing loot.json.

Download Ostraplan-v0.14.0.exe below: a single self-contained file, no .NET install needed. Just double-click.

Get your ship in-game (0.13.0)

Exporting a design can now make it directly obtainable in a playthrough, straight from the export dialog:

• Ship broker kiosks — add your ship to any station's regular used-ship stock (OKLG / BCER / BCRS / Venus / VORB), at an editable weight. Other ship mods' entries in the same kiosk are preserved.
• Special Offer — pin your ship to a station's free-ship-when-you-own-nothing slot. (Note: the game always lists Special Offer ships at "$0" — the real price shows on the Confirm dialog. It's a game quirk, use a broker kiosk for a visible list price.)
• Starting ship — offer it as a weighted option in a fresh Shipbreaker start (editable station + mortgage). No other mod required.
• Replace an existing ship — pick any vanilla or modded ship and your design takes over its identity, spawning in its place everywhere. Perfect for retrofitting: import a vanilla hull, rebuild it with your installed parts mods, and export it back over the original.
• Ship identity fields — set the in-game name (kept sticky now) plus make / model / year / designation / description.
• One-click register with Ostrasort — when staging into your Mods folder, hand the mod to Ostrasort to register it (and patch kiosk conflicts). Ostraplan still never writes loading_order.json itself.

Fixes in the same batch: exported ships no longer spawn inside the sun, and a custom in-game name now sticks across spawns.

Friendlier replacement-mod names (0.14.0)

Replacement mods are now named distinctly from the ship they override — defaulting to "{replaced ship} - Replaced via Ostraplan" — with a new editable Mod name field. The export dialog also explains the Special Offer "$0" quirk (decompile-confirmed: the ship's value is correct; only the list label is hardcoded).

Also since v0.9.0

• Optional save backup (0.12.0) — "Update ship in save" can skip the backup copy when you're iterating (ticked-to-back-up stays the safe default).
• ITEMS palette — loose cargo on ships (0.11.0) — a new ITEMS tab drops food, ammo, tools, scrap and more onto floor tiles or into containers; loose items and stacks persist in the .oplan, export, save write-back, and PNG snapshot. Designs can be provisioned, not just built empty.
• Operational-state build defaults (0.10.0) — powered fixtures now build in their On state, so a design's rating reflects reality and an exported ship spawns with its systems working.
• Find and Replace All context-menu action — swap every copy of a part across the whole ship in one undo step.

Full details in CHANGELOG.md.

v0.9.0

Ostraplan v0.9.0 adds the ship-zone editor, clears out Haile's bug report (#1) with a batch of cargo and loose-item fixes, and introduces an optional one-click installer.

New

• Ship zones — drawn, editable, and preserved. Draw and manage Ostranauts' crew/trade zones (Haul, Barter, Forbid, plus the content trigger/spawn zones). They now survive import → export and import → save-edit instead of being dropped or silently relocated — which previously broke player storage/no-go setups and the scripted encounters wired to trigger zones. A new Zones panel lists them; Z toggles the overlay; click a zone to paint its tiles (drag to add, Ctrl-drag to erase, Shift-drag a box, double-click fills an enclosed room), each stroke one undo step. Edit sets name, type, target role, colour, and (under Advanced) content-zone fields.
• Optional one-click install. Ostraplan can copy itself to %LOCALAPPDATA%\Programs\Ostraplan and create Desktop and Start Menu shortcuts, so you have one place to keep and launch it instead of hunting for the downloaded exe. It offers this once on first run, and you can trigger it any time from Help ▾ ▸ Install Ostraplan / shortcuts. No admin rights, nothing written outside your user profile, and deleting that folder uninstalls it.

Fixed (issue #1)

• Exported inventories now spawn exactly as authored — right contents, right counts, right ×N stacks. A data/ships file spawns as a template, and the game was dropping contained items that weren't written the way a save writes them, refilling from default loot instead — so filled racks/bays came back empty and a weapon loaded with two stacks of five came back with only a couple. Cargo now carries the save-style data it needs to survive and to rebuild stacks at the authored count, and a stocked container no longer gets default loot piled on top.
• Nav-console modules and themed loose walls/floors show up in the container add-picker. The picker skipped cooverlay skins entirely, so a nav console offered none of its real modules and floors/walls showed only a single generic "Floor (Loose)". It now includes the skins, so nav modules (Controls, Flight Dynamics, Map, …) and every themed loose wall/floor are offered.
• "Make Loose Item" now works on walls, floors, and conduits — and keeps the theme. Loosening a Testudo wall yields the Testudo loose wall, mirroring what the game drops on uninstall.
• Fixtures on under-floor storage bins no longer false-flag as "already occupied". A sealed floor is treated as a valid build/stand surface, matching the game.

Changed

• Add-to-container quantity control is clearer and capacity-aware: no clear-button hiding the number, −/+ steppers, and the value is clamped to what actually fits ("of N", or "container full").
• The Problems list is now an expandable list with a View button that pans and zooms the canvas straight to the offending tiles.
• The update check raises a modal on launch when a newer release is out, rather than only revealing the toolbar Update button.

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Windows only. Download Ostraplan-v0.9.0.exe below and run it — it's self-contained, no .NET install required. Ostraplan reads data and sprites from your local Ostranauts install (found automatically) and never modifies the game or your saves.

v0.7.0

Ostraplan 0.7.0 adds loose-item placement, makes symmetric building predictable, and fixes ship valuation and RCS ratings.

Make Loose Item / Install item

Right-click a placed fixture — a sink, an appliance, a gas canister — and choose Make Loose Item to uninstall it into its packaged (loose) form on the tile, or Install item to do the reverse.

• Eligibility comes straight from the game's own install/uninstall jobs, so only genuinely uninstallable fixtures are offered (raw hull, walls and the fixed airlock never are).
• The swap keeps the part's tile, rotation and any cargo, in a single undo step.
• Contents are conserved — a gas canister stays charged across the swap.
• A loose fixture stops certifying its room; re-installing into a spot that no longer fits is flagged in Problems rather than blocked.

Placing arbitrary loose inventory (tools, food, consumables) is a separate flow, not in this build yet.

Symmetry now previews every mirror

With symmetry on, the placement ghost shows the cursor part and each of its mirror copies — green where the mirror will land, red (with the offending tiles tinted) where the placement law refuses it. Previously an ill-fitting mirror was a silent no-op, which read as "symmetry only works most of the time", especially on large ships where mirrors more often land on structure that isn't symmetric yet. Now you see exactly what will mirror before you click.

RCS thrusters are built in their ON state

The game installs an RCS cluster Off, and the maneuver rating doesn't count an Off thruster — so a designed ship used to read maneuver "O" and you'd have to power each thruster by hand after loading in game. Ostraplan now builds the identical On variant, so a design shows a real maneuver grade and an exported ship's thrusters work on spawn. (Imported ships keep whatever state they were saved in.)

Fixed: exported ships carry their real broker value

Export used to bake each room's physical volume into its value instead of the game's parts-based room value, so a spawned design read as nearly worthless at a broker until the game recomputed it on full load. It now bakes the same parts value the game does (and that Ostraplan already shows in the inspector).

Install

Download Ostraplan-v0.7.0.exe below and double-click it. It's a self-contained Windows executable — no .NET install required.

Verified against Ostranauts 0.15.1.6.

Full changelog: https://github.com/Valtora/Ostraplan/blob/main/CHANGELOG.md

v0.6.0

Ostraplan is an out of game ship planner for Ostranauts. Drag every buildable part, including your loaded mods, onto the game's exact tile grid, validated live against the game's own rules, so you know a design works before you lay a tile in game.

If it builds in Ostraplan, it builds in Ostranauts.

Download

Grab Ostraplan-v0.6.0.exe below and double click it. It is self contained, so no .NET install is needed.

Requires Windows, and a local Ostranauts install (Ostraplan reads the game's data and sprites at runtime, and ships no game assets).

What's inside

• Design on the real grid. Every buildable part across the game's eight tabs, game accurate autotiling, drag paint, box and hollow fill, symmetry, flood select, the Replace With tool, a ship wide reskin, group rotate, copy and paste, and unbounded undo and redo.
• Live validation (the Law). You cannot place what the game would refuse, and the ghost glows green and red with the offending tiles and the reason.
• Rooms, airtightness and Ship Rating. Flood fill compartments, room certification, and the six slot rating, ported from the game and parity tested against its own data.
• Bill of materials. Install kit counts for the whole ship or a selection.
• Import and export. Start from a core or modded template, or your own ship from a save, and export any design as a spawnable local mod.
• Edit your live ship. Import it with its identity, redesign out of game, and write it back into a copy of the save (crew, cargo, position and identity preserved, the original untouched).
• Containers and cargo. View any container's contents on the grid, and add, remove and rearrange loose cargo.
• Extras. PNG snapshots, a light and dark theme, an update check, an in app Report a Bug, and an on disk activity log for troubleshooting.

Mod aware

Resolves your loading_order.json exactly like the game, so modded parts show up in the palette. A design records the mods it needs, and opens read only if any are missing, so nothing is silently lost. Pairs with Ostrasort for registering and load ordering your mods.

Known limitations

There will absolutely be bugs and I need help from the community to squash them all. Please use the report bug button in-app to file an issue here on github. This is the best place for me to keep track and manage them all.

Ostraplan cannot draw Ship Zones yet. Any ship you import or export will lose or move its zones, so you will need to delete and redraw them. Ostraplan is under active development, and more updates over the coming weeks will address this.

Good to know

Fan made, and not affiliated with Blue Bottle Games, so please buy the game. Ostraplan ships no game assets. Save editing writes to a copy by default, but back your saves up anyway. If you find a bug, use Report a Bug in the Help menu.

Verified against Ostranauts 0.15.1.6.