Prefabs

A prefab is a piece of level you made once and place many times: a window frame, a market stall. Each placed copy is an instance. Edit the prefab and every instance changes.

Prefabs live in prefab sets, files your game loads. The editor can only add to a set your game has loaded.

Make a prefab

1. Select the brushes and entities.
2. Press Cmd [.
3. Enter a Prefab Name, choose the Target Set, and optionally a Category.
4. Click OK.

The editor draws a thumbnail for the browser. What you selected becomes the prefab's first instance.

Cmd Z undoes the whole thing: the prefab leaves the set and the selection is plain brushwork again. The set is left marked as changed, so save it when you do mean to keep one.

Place a prefab

1. Press Cmd Shift [. The prefab browser opens in the left panel.
2. Choose a Set and click a prefab. Type in the filter field to find one by name.
3. Move over a view. A box shows where it will go, resting on the surface under the cursor and snapped to the grid.
4. Click to place it. Right-click cancels.
5. Click the prefab in the browser again to place another. Press Esc when done.

Work with instances

Placing an instance and breaking one are each one undo step.

Edit a prefab

1. Shift-click an instance. The editor narrows to it, and the Selection panel says EDITING PREFAB.
2. Edit it like anything else. Changes are written back to the prefab.
3. Press Cmd N with nothing selected to finish.
4. Save with File → Save Modified Prefab Sets. Saving the map saves them too.