Streaming big maps¶

Big outdoor maps can hide what is far away, so the map costs what the player can see instead of everything it holds. The build sorts the map's meshes into chunks on a grid, and only the chunks near the camera get drawn.

Turning it on¶

1. Select nothing

   Press Escape so nothing is selected. The Inspector on the right then shows Map (worldspawn).

2. Add chunk_streaming

   Type chunk_streaming in the key field at the bottom, 1 in value, and click Add. (If it is already listed, just turn it on there.)

   

   You should see it listed with the other worldspawn keys:

   

3. Save the map

   The next build adds a TrenchDotStreamer to the map.

(Optionally) add chunk_size and load_radius the same way:

Streaming only hides meshes. Collision and scripts keep running everywhere, so it saves rendering cost, not physics or logic. Overlays, content spawned at runtime and anything on a moving door or train are never hidden.

The streamer follows the viewport's current camera, or an info_player_start while there is no camera. To pin it to one camera, set its camera_path from code after the build, since a rebuild replaces the streamer. It only runs in the game, so the Godot editor always shows the whole map.

As chunks come and go the streamer emits area_loaded(key, bounds) and area_unloaded(key, bounds), so you can stream your own content alongside:

streamer.area_loaded.connect(func(key, bounds): spawn_wildlife(bounds))

Streaming sections¶

Want to play several maps as one world without loading screens? Split it into sections and join them with connector rooms. Only one section is in the scene tree at a time. The next one loads in the background while the player explores, and swaps in while the player walks through a connector, lined up so the room around them stays exactly the same. This needs the Gameplay entities pack.

1. Build a connector room

   A corridor with a bend on each side, so neither end can be seen from its middle. Put an info_landmark in the middle, and two func_section_stream volumes, one covering each half, meeting in the middle. Add it to the prefab library so every copy is the same.

2. Paste it where two maps meet

   In each map that meets another, paste the connector where the two meet and name its landmark, for example lm_hall_cellar. Set each half's section to the section on that side and landmark to the landmark's name. Both maps get the same copy with the same names, turned the same way.

3. Bake lighting in every section map

   SDFGI only notices geometry a swap brings in once its cascades scroll, so a swapped in section would stay unlit. Baked lighting comes with the section.

4. Make a scene per section

   One scene per section with its built map, the usual way.

5. Add the streamer

   Add a TDSectionStreamer node to your world scene and set its first_section and its player, see TDSectionStreamer.