Scenario system
The scenario system allows save-based mods to be created, so that installing mods separately is not necessary. This allows for server side scripting, or to provide a separate objective than the vanilla freeplay (which is actually a scenario, just like the tutorial campaign).
Scenarios count as mods for the purpose of isolating achievements.
Creation
Creation of a scenario starts in the map editor. The map editor allows an author to save a map that they have created as a scenario. This allows players to add special scripting to the scenario.
There are two ways to create a scenario:
- Via the Map editor.
- Creating a new folder in the scenarios folder, and adding a control.lua.
Differences between scenarios, saves, and mods
There are a few differences between a scenario, a save, and a mod. In a way, a scenario takes parts from both.
- Scenarios, unlike mods, cannot add any prototypes to the game. The only type of scripting allowed in a scenario is scripting that would occur in control.lua.
- Scenarios can have premade maps, such as the supply scenario, or can have maps made with the map generator, such as freeplay.
- Scenarios do not need to be installed client side, unlike mods. This allows servers to implement small changes to gameplay on their end, such as displaying a MOTD to joining players.
- Scenarios, unlike normal saves, are stored in a different folder.
- Scenarios can be used to create a bit of a story, as the campaign does.
Playing a scenario
There are several scenarios included into the game by default. To play a scenario, click Play->Scenarios, and choose either a user scenario, or a scenario from the base game or mod. The Freeplay scenario is the same as the basic game, where the objective is to launch a rocket.
Upon choosing a scenario to play and saving the game, a normal save will be created that encompasses the map itself, and the control.Lua scripting that was provided by the scenario. This can be removed by deleting the script.dat and control.Lua files from the save, turning it into a normal save. Do this at your own risk, as it may break the save depending on how intertwined the scenario is with the save.
Installing scenarios
Scenarios made by other players can be installed into a folder called scenarios in the player's user data directory. It can then be played from the scenarios menu.
Scenarios added by mods are also shown in the Scenarios menu.
Scenario file structure
Scenarios do not have access to the settings stage and data stage parts of the Data Lifecycle. This means they rely entirely on runtime scripting via the control.lua file. Scenarios can contain a description.json file to mark them as multiplayer compatible.
Packaging a scenario in a mod
Scenarios must be packaged into a mod to be distributed on the mod portal.
Inside a mod add a "scenarios" folder, and copy your scenario into that folder. If you created a scenario with the map editor, you can find it in the scenarios folder in your user data directory.
description.json
A json file in the scenario folder that can have the following fields:
Example
{
"multiplayer-compatible": true,
"order": "d"
}
Localization of scenario name and description
Scenario name and description, which are seen in the "Start a new game" scenario selector are localised using locale files inside the scenario. The keys are scenario-name and description, both without a [category]. Example from freeplay/locale/en/freeplay.cfg:
scenario-name=Freeplay description=Your task is to launch a rocket into space. Start from nothing, work your way up with automation, and don't forget to protect yourself from the natives.\n[font=default-bold]This is the intended way of playing Factorio.[/font]