Skip to content

Production & Tech Nodes

SIM Functions from USeinProductionBPFL. These query production availability and tech state — essential for building production panels and tech tree UI.

Functions

SeinGetProductionAvailability

SeinGetProductionAvailability(PlayerID, BuildingEntity) → TArray<FSeinProductionAvailability>

The primary function for building production panels. Returns one entry per producible item on the building, with full availability state:

Field Type Description
ActorClass TSubclassOf<ASeinActor> The producible archetype
bPrerequisitesMet bool Player has required tech tags
bCanAfford bool Player has enough resources
bQueueFull bool Building's production queue is at capacity
bAlreadyResearched bool Research item already completed

Use this to drive button states in production panels:

For each FSeinProductionAvailability:
  if AlreadyResearched → Hide or gray out
  elif not PrerequisitesMet → Disabled state, show "Requires: ..."
  elif not CanAfford → Unaffordable state, red cost text
  elif QueueFull → Disabled state
  else → Available state

SeinCanPlayerProduce

SeinCanPlayerProduce(PlayerID, ActorClass) → bool

Quick boolean check — can this player produce this unit/research? Checks prerequisites and affordability. Use for simple enable/disable without the full availability breakdown.

SeinPlayerHasTechTag

SeinPlayerHasTechTag(PlayerID, TechTag) → bool

Returns true if the player has unlocked the given tech tag. Tech tags are granted when research completes.

SeinGetPlayerTechTags

SeinGetPlayerTechTags(PlayerID) → FGameplayTagContainer

Returns all unlocked tech tags for a player. Use for tech tree visualization or prerequisite display.

Production System Overview

How Production Works

  1. Player clicks a production button on a building
  2. QueueProduction command enters the command buffer
  3. Sim validates: prerequisites met? Can afford? Queue not full?
  4. If valid: deducts resources, adds to building's queue
  5. Each tick: front item's build timer counts down
  6. On completion:
  7. Unit: Entity spawned at rally point, EntitySpawned visual event
  8. Research: Tech tag granted to player, archetype modifiers applied, TechResearched visual event

Cancellation and Refunds

  • CancelProduction command removes the last queued item
  • Resources are fully refunded on cancellation
  • Only the last item can be cancelled (LIFO)

Rally Points

  • SetRallyPoint command sets where produced units spawn/move to
  • Stored on FSeinProductionComponent
  • Visual rally point marker is render-side only

Tech Tree

There is no explicit tech tree asset. The tech tree is emergent from the prerequisite chains:

Building A produces Research X
  → Research X grants TechTag "Tech.Weapons.Tier1"
    → Building B requires "Tech.Weapons.Tier1" to produce Unit Y

To visualize the tech tree in UI, walk the archetype definitions and build a dependency graph from PrerequisiteTags → GrantedTechTag relationships.

UI Integration

For production panel buttons, use the UI Toolkit's action slot builder:

SeinBuildProductionSlotData(BuildingEntity, PlayerID)
  → Returns TArray<FSeinActionSlotData>

This packages production items into the same FSeinActionSlotData format used by abilities, with State reflecting availability (prerequisites, affordability, queue state). See UI Toolkit Nodes.