Saving, live mode and hot reload¶

Rebuild on save¶

Keep the scene with your FuncGodotMap open in the Godot editor and just save in TrenchDot with Ctrl+S. Godot rebuilds that scene straight away, as long as its tab is the one Godot shows and the map node has Auto Rebuild On Save on. A scene in another tab that uses the map rebuilds when you switch to its tab. Closing and reopening a tab or reloading a scene does not break this. Saving a prefab rebuilds the maps of that scene that use it, directly or through another prefab.

The status bar at the bottom left tells you what Godot did. When it worked, it should say:

The status bar saying "Live link: Godot rebuilt 1 map node(s)"

Save the scene in Godot to keep the result. If the status bar says something else, the message tells you why:

The status bar saying room.tscn uses room.tdm but is not the current scene tab in Godot, it rebuilds when you switch to it

The status bar says	Do this
The scene is not the current scene tab in Godot	Switch to that tab, it rebuilds then
The current scene tab has no `FuncGodotMap` for the map	Open the scene that builds the map, or turn on Auto Rebuild On Save on its map node
Godot has no scene open	Open the scene with the map in Godot, and if it is open, read on
Godot is not running with the TrenchDot addon	Open the project in the Godot editor with the addon enabled
Godot rebuilt the map, but the map settings have no definition for some classes, so they build as plain nodes	Add the definitions, see Entities that do nothing
Godot rebuilt the map with warnings, see the Issues panel	Read them in the Issues panel, where they start with "Godot:"

Only one Godot editor can hold the live link port. A second editor with the same project warns in its Output panel that the live link could not listen, and TrenchDot keeps talking to the first one, which may have no scene open. Close the editor you do not use and the other one takes the link over within a few seconds. (Note: Godot > Open Project in Godot Editor brings an editor that already has the project to the front instead of starting a second one.)

Live mode¶

Live mode pushes your edits into the scene open in the Godot editor before you save, so you can judge lighting and scale in the real renderer.

Open the scene in Godot

The map has to be saved inside the project once, and the scene open in Godot needs a FuncGodotMap that uses it.
Turn it on

Click the link button at the right end of the toolbar, next to the Godot robot, or use Godot > Live Mode. The button lights up, and its tooltip says what it is still waiting for, if anything.
Edit as usual

Every change shows up in Godot right away.

Live mode needs the Godot live link, which is on by default. Both sit in File > Preferences, where Godot live mode is the same switch as the toolbar button.

The Godot live link, Godot live mode and Running game hot reload rows in Preferences

Drags move nodes while you drag, and most edits rebuild only what they touched, so the preview keeps up. Toggling Omit From Export on a layer and editing prefab instances rebuild the whole map instead, once you pause.

The preview is close to a full build but not always identical. Saving always does a full build, and quitting without saving sends Godot back to the saved file, so nothing you tried in live mode sticks unless you save it.

When live mode rebuilds the whole map¶

Godot rebuilds the whole map by itself when the scene no longer matches what a full build would give. When live mode starts on a scene it does so right away, otherwise once you pause editing:

When	Why
Live mode starts on a scene that was built with other entity definitions	The scene was built before you installed the Gameplay entities pack or added a definition, so some entities are plain nodes
Live mode starts on a scene that earlier live edits changed	The scene still holds live edits of an earlier session that you never saved
The entity definitions change while live mode runs	You saved an FGD or a definition in Godot's Inspector, a script class changed, or new files arrived, like an installed pack
You save a prefab the map uses	The scene still shows the prefab as it was

Open scenes outside live mode keep their entities as they were built, and Godot's Output panel warns when one of them was built with other entity definitions. Press Build Map in it and save.

Entities without a definition¶

When live mode builds an entity whose class Godot has no definition for, the status bar names the class and the FGD to add it to:

The status bar saying Godot has no definition for crypt_lamp, it shows a plain node, add the class to the FGD of res://crypt_settings.tres

The live mode button's tooltip keeps the same note while the map uses that class:

The live mode button switched on, its tooltip saying edits reach Godot before you save, and that Godot has no definition for crypt_lamp

Add the definition and save it, and Godot rebuilds the map by itself. The note goes away with your next save. See Entities that do nothing for where a definition goes.

Hot reload in a running game¶

To see your saves in a game that is already running:

Add the autoload

In Godot, go to Project > Project Settings > Globals > Autoload and add this script:
```
res://addons/func_godot/src/trenchdot/runtime/trenchdot_hot_reload.gd
```
Run the game from the Godot editor

The autoload only listens in games started from the Godot editor, unless you set its enabled_in_exported_builds to true.
Save in TrenchDot

The game rebuilds the maps that use the saved file and emits map_reloaded(map). Use that signal to put the player back at a spawn point or reset game state. The status bar should end with "running game reloaded 1 map(s)".

It listens on port 7843, which must match Running game hot reload in the editor's preferences. TrenchDot only sends it saves while the live link is on.