ProximitySensor

Sensor subclass that detects authorised humans inside a sphere centred on the sensor. Detection is pure euclidean squared distance against Human.AllHumans. No line-of-sight, no raycast, no grid / room / atmosphere consideration. Walls, floors, terrain, and planetary surface are all transparent to it. Differs sharply from MotionSensor (single-cell grid event source) despite both being Sensor subclasses with IDoorControl.

Class shape and fields

public class ProximitySensor : Sensor, IDoorControl
{
    private int _setting = 2;
    private static int MaxSetting = 250;

    [SerializeField]
    private Knob knob;

    public override bool IsTriggered => Activate > 0;

    public int Setting
    {
        get => _setting;
        set
        {
            value = Mathf.Clamp(value, 0, MaxSetting);
            _setting = value;
            knob.SetKnob(Setting, MaxSetting).Forget();
            if (Assets.Scripts.Networking.NetworkManager.IsServer)
                base.NetworkUpdateFlags |= 256;
        }
    }
    ...
}

• Setting is the detection radius in metres. Clamped to [0, 250]. Default 2.
• IsTriggered is true whenever the count of detected humans is non-zero (Activate > 0).
• The serialised knob field drives the in-world UI; turning Button1 / Button2 adjusts Setting by 1 (or 10 with Alt).
• Network delta flag 256 carries Setting (single byte) to clients via BuildUpdate / ProcessUpdate and on join via SerializeOnJoin / DeserializeOnJoin. Maximum representable byte is 255, so the on-wire cap matches the MaxSetting = 250 clamp.

Detection: squared-distance check, no occlusion

public override void OnThreadUpdate()
{
    base.OnThreadUpdate();
    if (!GameManager.RunSimulation) return;
    int num = 0;
    foreach (Human allHuman in Human.AllHumans)
    {
        if (Vector3.SqrMagnitude(allHuman.Position - base.Position) < (float)(Setting * Setting) && IsAuthorized(allHuman))
        {
            num++;
        }
    }
    if (Activate != num)
        OnServer.Interact(base.InteractActivate, num);
}

Key facts:

• Iterates Human.AllHumans every OnThreadUpdate tick (server-only via GameManager.RunSimulation).
• Uses Vector3.SqrMagnitude against Setting * Setting (squared comparison avoids sqrt). Detection radius is exactly Setting metres in 3D world space.
• No Physics.Raycast, no WorldGrid adjacency, no Cell containment, no AtmosphericsController.SampleGlobalAtmosphere, no room / structure / wall check anywhere in the detection path. The sensor sees every authorised human within radius regardless of intervening geometry.
• IsAuthorized(allHuman) filters by the sensor's authorisation list (inherited authorisation surface), but does not affect line of sight.
• Activate becomes the count of detected humans, not a boolean. Multiple authorised humans inside the sphere produce Activate = N.

LogicType surface

public override bool CanLogicRead(LogicType logicType) => logicType switch
{
    LogicType.Setting => true,
    LogicType.Quantity => true,
    _ => base.CanLogicRead(logicType),
};

public override bool CanLogicWrite(LogicType logicType) => logicType switch
{
    LogicType.Setting => true,
    LogicType.Activate => false,
    _ => base.CanLogicWrite(logicType),
};

public override void SetLogicValue(LogicType logicType, double value)
{
    if (logicType == LogicType.Setting) Setting = (int)value;
    base.SetLogicValue(logicType, value);
}

public override double GetLogicValue(LogicType logicType) => logicType switch
{
    LogicType.Setting => Setting,
    LogicType.Quantity => Activate,
    _ => base.GetLogicValue(logicType),
};

• Setting is readable and writable (sphere radius in metres).
• Quantity is readable, returns Activate (count of authorised humans in range).
• Activate is explicitly NOT writable. Boolean trigger state surfaces on the inherited On / Open paths depending on what the inherited Device / Sensor chain exposes; nothing new is added here.
• Setting Setting via logic clamps through the property setter [0, 250].

Save format

public class ProximitySensorSaveData : StructureSaveData
{
    public int Setting;
}

Only Setting persists. Activate is recomputed each tick from live human positions.

Motherboard hookup

public override void SetMotherboards(bool isTriggered)
{
    foreach (Motherboard linkedMotherboard in LinkedMotherboards)
    {
        if (linkedMotherboard is Circuitboard circuitboard && circuitboard.ParentComputer.AsDevice().Powered)
        {
            circuitboard.RemoteToggle(isTriggered);
        }
    }
}

Same shape as Sensor.SetMotherboards plus a circuitboard.ParentComputer.AsDevice().Powered gate: a powered-down computer's circuitboards are skipped.

Interaction (knob)

public override DelayedActionInstance InteractWith(Interactable interactable, Interaction interaction, bool doAction = true)
{
    ...
    switch (interactable.Action)
    {
    case InteractableType.Button1:
        delayedActionInstance.ActionMessage = GameStrings.GlobalDecrease.AsString();
        delayedActionInstance.AppendStateMessage(GameStrings.GlobalRadius, StringManager.Get(Setting));
        if (!doAction) return delayedActionInstance.Succeed();
        knob.PlayKnobSound(Setting, increase: false, MaxSetting);
        Setting = Mathf.Max(Setting - ((!interaction.AltKey) ? 1 : 10), 0);
        knob.SetKnob(Setting, MaxSetting).Forget();
        return DelayedActionInstance.Success(interactable.ContextualName);
    case InteractableType.Button2:
        ... // mirror of Button1, +1 or +10
    }
}

Button1 decreases radius, Button2 increases. Alt-modifier multiplies step from 1 to 10. Contextual name resolves to InterfaceStrings.Radius.

Behavioural consequences

• Walls, doors, steel sheets, and full base interiors do not block detection. A ProximitySensor in a bunker triggers on a player walking past outside, provided they are within Setting metres of the sensor in straight-line 3D distance.
• Floors are equally transparent: a sensor on the top floor of a multi-level base will trigger on humans below or above within radius.
• Terrain and planetary surface are not consulted. Underground caverns within radius register.
• Z-axis distance counts the same as XZ; the sphere is true 3D.
• Only Human instances count. Non-human DynamicThing (livestock, rovers, suits without an occupant) do not trigger this sensor. (For dynamic-thing detection on a grid cell, see MotionSensor.)
• Authorisation filtering excludes non-authorised humans from the count entirely. With Quantity wired into logic, this effectively gives an authorised-headcount-in-radius read.

Verification history

• 2026-05-18: Page created from Assembly-CSharp.decompiled.cs line 394549. Detection mechanism, LogicType surface, save format, knob interaction, and motherboard gate captured verbatim. Explicit determination: no LOS / occlusion / grid check in the detection path. No prior page existed.

Open questions

None.