Slot EngineData Service
Service for interacting with the book data or recorder.
Introduction
Slot Engine has data layers that store JSON data required for game optimization, statistical analysis and frontend visualization.
Book
Each simulation produces a "book" that contains information about the simulation, like simulation ID, payout values, and JSON data for frontend visualization.
The book stores events as an array of objects with an index, type and arbitrary data. Events define, in chronological order, what should be displayed to the player on the frontend.
Common events include:
- Revealing the board symbols
- Displaying win lines
- Displaying win amount
- Trigger free spins screen
In short: (Almost) every visual change on the frontend for a single spin is defined inside a book.
For example:
ctx.services.data.addBookEvent({
type: "show-winlines",
data: {
lines: [0, 3]
wins: [
[
{ reel: 0, row: 0 },
{ reel: 1, row: 0 },
{ reel: 2, row: 0 },
],
[
{ reel: 0, row: 2 },
{ reel: 1, row: 2 },
{ reel: 2, row: 2 },
],
]
}
})
ctx.services.data.addBookEvent({
type: "add-update-balance",
data: {
value: 200,
}
})Each added event receives an auto-incremented index, allowing the frontend to process events in the correct chronological order.
Recorder
The recorder allows grouping simulations by arbitrary criteria. If using optimization, this would allow you to target specific simulations to optimize. It also enables capturing notable runs (e.g. max win simulations) so they can be replayed locally for debugging or demonstration.
Records are written to the __build__ directory as force_record_<gameMode>.json. The JSON structure matches the Stake Math SDK format for interoperability.
Without having to configure anything, Slot Engine automatically groups simulations by their result set criteria.
You can add additional records as needed using record().
Methods
addBookEvent()
| Method | Type |
|---|---|
ctx.services.data.addBookEvent() | (event) => void |
Parameters
| Parameter | Type |
|---|---|
event | { type: string, data: Record<string, any> } |
Adds a new event to the current book.
record()
| Method | Type |
|---|---|
ctx.services.data.record() | (data) => void |
Parameters
| Parameter | Type |
|---|---|
data | Record<string, string | number | boolean> |
Record data for statistical analysis.
recordSymbolOccurrence()
| Method | Type |
|---|---|
ctx.services.data.recordSymbolOccurrence() | (data) => void |
Parameters
| Parameter | Type |
|---|---|
data | { kind: number; symbolId: string; spinType: SpinType; [key: string]: any; } |
A wrapper around ctx.services.data.record() to record symbol occurrences.
Use of AI on this page: All texts were initially written by hand and many were later revised by AI for improved flow. All AI generated revisions were carefully reviewed and edited as needed.