Rope Bridge

Based on game build 714014 | Last updated: 2026-03-07

Overview

The rope_bridge system defines the game representation and behavior of rope bridges. It includes three prefabs: rope_bridge_fx (the actual bridge entity), rope_bridge_kit (the crafting item used to place bridges), and rope_bridge_kit_placer (the visual placement helper). The system coordinates with the ropebridgemanager component for bridge placement logic, and interacts with deployable, stackable, inventory, and placer components for functionality. It handles animation state transitions, sound effects, quaking detection, and minimap icon rendering.

Usage example

-- Placing a rope bridge via inventory item
local bridge_kit = SpawnPrefab("rope_bridge_kit")
bridge_kit.components.stackable:SetStackSize(3)

-- The bridge_kit uses DEPLOYMODE.CUSTOM with a custom deployment function
-- Deployable behavior is configured in kitfn():
--   inst.components.deployable.ondeploy = OnDeploy
--   inst.components.deployable:SetDeployMode(DEPLOYMODE.CUSTOM)

-- At placement point, OnDeploy is called with target point and deployer
-- It checks for ropebridgemanager and spawns bridge segments via QueueCreateRopeBridgeAtPoint

Dependencies & tags

Components used: deployable, stackable, fuel, inventoryitem, placer, ropebridgemanager, quaker, inventory, inspectable.
Tags: NOCLICK, decor, FX, CLASSIFIED, placer, deploykititem, usedeployspacingasoffset.

Properties

Property	Type	Default Value	Description
killed	boolean	false	Indicates whether the bridge has been destroyed.
rope1, rope2	entity	nil	Child entities for left/right rope visuals.
icon	entity	nil	Minimap icon entity.
animdata	net_smallbyte	—	Networked animation state data (packed byte).
iconoffset	net_tinybyte	0	Networked icon offset data for minimap display.
pos	Vector3	—	Internal placement helper position (placer only).
pieces	table	{}	Array of bridge segment entities (placer only).
numvisiblepieces	number	0	Count of currently visible placement preview pieces (placer only).

Main functions

Rope_KillFX(inst)

• Description: Triggers bridge rope destruction animation and prepares entity removal. Only activates once per bridge instance.
• Parameters: inst (entity) — the bridge instance to destroy.
• Returns: Nothing.
• Error states: Early exit if inst.killed is already true.

CreateRope()

• Description: Creates and configures a single rope visual entity (no physics, non-persistent, parented to bridge).
• Parameters: None.
• Returns: entity — newly created rope entity with ANIM_ORIENTATION.BillBoard, bank "rope_bridge", and KillFX method attached.

OnAnimData(inst)

• Description: Updates rope animations based on packed animdata value. Called on non-master clients when animdatadirty event fires.
• Parameters: inst (entity) — bridge instance with animdata network component.
• Returns: Nothing.

GetAnimDataForState(inst, state)

• Description: Encodes the current state (place, idle, shake, break) into the animdata byte while preserving rope variation bits.
• Parameters: inst (entity), state (string) — animation state identifier.
• Returns: number — updated packed animation data value.

SkipPre(inst)

• Description: Transitions bridge from placement animation directly to idle state, canceling sounds.
• Parameters: inst (entity) — bridge instance.
• Returns: Nothing.

ShakeIt(inst)

• Description: Initiates bridge shaking animation and looped sound effect, unless bridge is killed or asleep.
• Parameters: inst (entity) — bridge instance.
• Returns: Nothing.

KillFX(inst)

• Description: Triggers bridge destruction sequence: plays break sound, sets up break animation, and schedules removal.
• Parameters: inst (entity) — bridge instance.
• Returns: Nothing.

SetIconOffset(inst, offset)

• Description: Updates minimap icon visibility and position based on offset value (0: hidden, 1: center, 2: offset).
• Parameters: inst (entity), offset (number or nil).
• Returns: Nothing.

CLIENT_CanDeploy(inst, pt, mouseover, deployer, rotation)

• Description: Validates whether a rope bridge can be deployed at a point, checking quaking state, deployment constraints, and stack/inventory availability.
• Parameters:
  inst (entity) — bridge kit item,
  pt (Vector3) — target placement point,
  mouseover (boolean) — whether targeting via mouse,
  deployer (entity) — player attempting placement,
  rotation (number) — rotation value (unused).
• Returns: boolean — true if deployment is valid and sufficient resources exist.
• Error states: Returns false if quaking is active or deployment constraints fail.

OnDeploy(inst, pt, deployer)

• Description: Master-side deployment handler. Consumes bridge kits or items, then queues bridge segment creation through ropebridgemanager.
• Parameters: inst (entity) — bridge kit item, pt (Vector3), deployer (entity).
• Returns: Nothing.
• Error states: Early exit if ropebridgemanager missing, deployment check fails, or insufficient resources.

placer_onupdatetransform(inst)

• Description: Placement helper callback. Updates bridge segment preview positions, orientations, and tinting (green=valid, red=invalid) based on deployment feasibility.
• Parameters: inst (entity) — placer helper instance.
• Returns: Nothing.

placer_oncanbuild(inst, mouseblocked)

• Description: Placement helper callback. Controls helper visibility and inventory icon based on build state.
• Parameters: inst (entity), mouseblocked (boolean).
• Returns: Nothing.

placer_oncannotbuild(inst, mouseblocked)

• Description: Placement helper callback. Toggles visibility and icon if build invalid and preview pieces exist.
• Parameters: inst (entity), mouseblocked (boolean).
• Returns: Nothing.

Events & listeners

• Listens to: animover (on rope_bridge_fx) — transitions from bridge_place to bridge_idle, removes entity if killed.
• Pushes: animdatadirty, iconoffsetdirty (network events for rope_bridge_fx to synchronize client visuals).
• Deploy callbacks: CLIENT_CanDeploy, OnDeploy — used internally by deployable component (DEPLOYMODE.CUSTOM).