Socketwright - Modular Kit Sockets and Snap Placement for Unity

Point it at a folder of modular kit prefabs. It reads the meshes and writes the connection sockets for you. Then drop a piece near another one and it snaps, rotation resolved.

Other modular snapping tools make you place every socket by hand, piece by piece, in a custom editor. Socketwright derives them from the geometry, for the whole kit, in one pass: an opening socket in every hole of a piece's boundary faces (corridor ends, doorways cut into a room) and an edge socket on every thin, full boundary face (wall ends, floor edges, wall tops for stacking). The size of the hole or edge becomes the mating type, so a 3.5 x 3 corridor end only mates with another 3.5 x 3 opening.

Measured on Unity 6000.5.7f1

• The 11-piece demo kit ships with NO hand-placed sockets. Socketwright derived 33 sockets from the meshes and detected the 4 m module by itself. The demo level was then assembled through those sockets, every joint mated.
• A 200-prefab kit derives and writes in one pass: 602 sockets, every prefab saved.
• Installed from the shipped .unitypackage into a blank project: 27 of 27 tests passed on the installed bytes, including snap, undo, attach chains, stacking, audit and fix, and the hostile cases (empty objects, degenerate meshes, missing folders, a piece that fits nothing).

What you do with it

1. Tools > CSAF > Socketwright > Kit Window. Pick your kit folder, press Preview sockets (changes nothing), then Write sockets.
2. Drag and drop. Move a piece near another and let go: the dotted amber line shows the socket pair while you drag, and the piece snaps on release. One Undo step.
3. Click to attach. Select a placed piece, click a piece in the palette: it attaches to the nearest free socket, and the selection moves on to the new piece's far end, so click, click, click builds a corridor.
4. Audit the kit. Finds sockets off the module grid (a wall modelled 3.98 m long pushes every piece after it off grid) and moves them back; flags mating types nothing else in the kit carries.
5. Export a Kit Sheet. One HTML page: every piece drawn isometrically from its own mesh, its sockets in their type colours, a legend of what mates with what. Hand it to the level designer who did not build the kit.

It also works at runtime

The sockets are a small runtime component, so the same data drives procedural levels. KitAssembler.Attach(prefab, socket) mates a piece in code. The demo scene's generator grows a 27-piece corridor network from free sockets when you press Play, rejecting overlaps.

Good to know

• Sockets are derived from the six faces of each piece's bounds. A connection in the middle of a curved, sculpted piece cannot be derived: add that one by hand (hand-placed sockets are never overwritten).
• A window or door through a thin wall is not treated as a connection; the Preview lists it as a near miss with the reason, as it does for every face it skipped.
• Writing sockets edits your prefab files. Use version control. Remove derived takes them all out again.
• Tested on Unity 6000.5.7f1. Written against APIs available since 2022.3 but not run there.
• The demo kit uses Built-in Standard materials; convert them for URP or HDRP with Unity's converter. The tool itself is pipeline independent.

What is in the download

A .unitypackage plus the same files as a plain folder: the runtime and editor source in C#, each in its own assembly (editor code never enters your build), the 11-piece demo kit (corridors, a hub room, floor tiles, walls, a pillar) with its demo scene, the numbered offline guide, the Readme and the licence. No Resources folder.

Also from the studio

Statewright ($19.99): an Animator Controller workspace, with bulk transition editing and states built from clips.
Clipwright ($14.99): trim, retime, mirror and loop animation clips in batch.
All of our Unity tools: Unity Editor Tools.

Socketwright, its demo kit and its documentation were written with AI assistance (code and store images). The cover is a designed title card over a render of the demo level. Tested by us as described above.