Give your mountain
a story to play.

STEP 01

Open a source project

The workshop edits a folder containing custom-map.json, its terrain and its scripts. A map downloaded from Featured is a playable package. For authoring, use the source project rather than its installed package.

skieomod editor first-season

For Super Saint-Bernard in a repository checkout, open mod/SkiEO-SuperSaintBernard. Make a separate copy before experimenting. To start from your own terrain, use New or the heightmap tutorial, then Save.

This tutorial uses the workshop build with Configure scenario and Register before project script. If either control is missing, update the tools to a release containing this tutorial, or run this repository's workshop with its Qt dependencies installed. The scenario APIs in the game require Custom Map 1.19.3 or newer.

pipx install --force --index-url https://skieomap.emillon.fr/downloads/pypi/ skieo-custom-map
skieomod update

For a first installation, run skieomod setup instead of update. Click Triggers in the toolbar. The practice project already contains two visual triggers and Project initialization • Lua.

Checkpoint: the Trigger Editor opens with a trigger list on the left, a graph in the centre and node properties on the right.

STEP 02

Connect an event to an action

A trigger waits for its selected event. When that event occurs, the white execution connections tell it which actions to run. Coloured connections supply the data those actions need. A value connection alone does not execute an action.

api:log('My first scenario is ready.')

Add nodes with Add node… or right-click. Drag from an output pin to a compatible input pin. Each input accepts one link. Use the wheel to zoom, middle-drag to move around, and Undo to correct a change. Select a node or link and press Delete to remove it.

STEP 03

Super Saint-Bernard's starting economy

Select Starting economy · 2003. This is a converted part of the actual scenario's map.ready initialization: it configures the session with 250,000 CHF, a 38 CHF ticket and historical reference year 2003.

local rules = require('economy')
api.game:configure({
    currency = 'CHF', start_year = 2003,
    starting_balance = 250000, ticket_price = 38,
    costs = rules.costs, class_costs = rules.class_costs,
    loans = rules.loans,
    track_lift_rides = rules.track_lift_rides
})

Configure scenario sets starting cash and ticket price only on a new game. A restored save keeps its current cash and ticket price. start_year is used by the script's historical calendar; the native game date and money symbol remain visible. In Super Saint-Bernard, native Year 1 represents the 2003–2004 season.

The graph and Lua sources are retained separately. Switching modes selects which source is compiled; it does not translate later edits. If you change the graph's amount, update the optional Lua equivalent before using that mode.

Checkpoint: your new test starts with the chosen cash and ticket price. Loading an older save does not reset its economy.

STEP 04

Run an action only in April

Select April reminder in the practice map, or create it on your map. This exercise introduces a condition without changing Super Saint-Bernard's rescue payments.

if (event.month or 0) == 4 then
    api:log('April: check your cash reserve.')
end

Delay waits a Number of seconds before continuing a white connection. It uses runtime timers; a delay is not a calendar month or year. Use calendar events for seasonal rules. Add funds changes the cash balance; it does not record scenario revenue. A one-time rescue grant also needs saved state so reopening a save or reaching April again cannot pay it twice.

STEP 05

Make it a playable scenario

The practice map already has a briefing and two objectives: reach April 2004 with at least 100,000 CHF left. A negative cash balance fails the scenario immediately. You can place a Ticket Office and a lift, sculpt or import your terrain, then build a resort within that budget.

Keep using visual graphs for events, starting values and simple actions. The objective panel, saved progress and victory/failure evaluator currently use the scenario Lua API. The included starter supplies those parts so you can begin by changing the graphs.

local state = api:state({status = 'active', balance = 250000})
api:scenario({
    title = 'My first season',
    briefing = 'Reach April 2004 with a cash reserve.',
    goal = 'Finish with at least 100,000 CHF.',
    deadline = 'April 2004',
    status = function() return state.status end,
    objectives = {{
        label = 'Keep a cash reserve',
        progress = function()
            return {
                value = string.format('%.0f CHF', state.balance),
                fraction = math.max(0, math.min(1, state.balance / 100000))
            }
        end
    }}
})

STEP 06

Build, then test the rules

Click Apply to project in the Trigger Editor, close it, then Save → Build → Test → Play. Build validates graph types, missing inputs and cycles, then compiles the enabled graphs and Lua triggers into the package's entry script.

skieomod build first-season
skieomod test first-season --check-scripts
skieomod run first-season

--check-scripts requires Lua 5.4 / luac; syntax validation does not execute your gameplay rules. Omit this option if the compiler is unavailable. Play is where you check the scenario's behaviour. Editor Play starts its own fresh test instance and reloads that instance after a rebuild.

• Fresh start: verify the briefing, initial cash, ticket price and objective text.
• Calendar: let April arrive and check that the reminder appears in the UE4SS log, with the expected victory or failure result in the game.
• Failure: on a disposable test, create a deficit and check that the scenario fails. For a fast deadline test, use a copied starter script with an earlier deadline.
• Restoration: save after spending some cash, reload and verify that cash and scenario progress resume. Repeat with a completed or failed scenario.

Checkpoint: saving and reopening preserves progress; rebuilding then starting a new test uses your edited source values.

The files behind the graph

custom-map.json                Source manifest and build settings
Triggers/triggers.json         Graphs, Lua equivalents, events and enabled flags
Scripts/main.lua               Project initialization and scenario evaluator
Scripts/economy.lua            Advanced rules module (Super Saint-Bernard only)
bin/*.skieomap                 Built playable package

The source manifest keeps its original script entry and links the trigger source:

"script": {
  "language": "lua", "api": "1.1",
  "entry": "Scripts/main.lua", "permissions": ["gameplay"]
},
"build": {
  "triggers": {"file": "Triggers/triggers.json"}
}

Merge these settings into your existing manifest, preserving terrain, vegetation, resources and scene settings. Local Lua modules need to be declared in content.assets, such as Scripts/economy.lua, along with their module dependencies.

Build creates Scripts/skieomod-generated-authoring.lua inside the package. Edit the source graph or project Lua and rebuild. The generated entry is not the authoring file. Raw pack archives files; use build to compile your graph first.

Super Saint-Bernard's actual trigger JSON ↓ · April reminder trigger JSON ↓ · API and source format reference ↗

The starting-economy JSON references the real economy module. Use it with the Super Saint-Bernard source, or clear Rules module before adapting it to another map. To add the reminder to an existing project, merge its trigger entry into the existing triggers array rather than replacing your other triggers.

When a trigger does not behave as expected