Class BaseEventTrigger

Namespace: mobisim.Event

Abstract base class providing the shared infrastructure for invoking UnityEvents when an object enter or exit a trigger collider.

public abstract class BaseEventTrigger : MonoBehaviour, IDataLoggable

Inheritance

object→Object→Component→Behaviour→MonoBehaviour→BaseEventTrigger

Derived

• CollisionEventTrigger
• EventTrigger

Implements

IDataLoggable

Examples

Override OnTriggerEnter / OnTriggerExit in a subclass to apply filtering, then delegate to Collider) / Collider) so that the base class handles the enabled-check, one-shot guard, and logging.

using UnityEngine;
using mobisim.Event;

public class TagFilteredEventTrigger : BaseEventTrigger
{
    [SerializeField] private string _requiredTag = "Player";

    private void OnTriggerEnter(Collider other)
    {
        // Resolve the actor root: child colliders on compound Rigidbodies report themselves,
        // not the root GameObject that carries the tag.
        var root = other.attachedRigidbody
            ? other.attachedRigidbody.gameObject
            : other.gameObject;

        if (root.CompareTag(_requiredTag))
            TriggerEnterEvent(other);   // base handles enabled-check and _onlyTriggerOnce
    }

    private void OnTriggerExit(Collider other)
    {
        var root = other.attachedRigidbody
            ? other.attachedRigidbody.gameObject
            : other.gameObject;

        if (root.CompareTag(_requiredTag))
            TriggerExitEvent(other);
    }
}

Remarks

This class has two distinct responsibilities:

• Event dispatch — exposes Collider) and Collider) as virtual entry points that subclasses call after applying their own filtering logic (tag checks, layer masks, distance tests, etc.).
• Data logging — implements IDataLoggable so that every trigger interaction is automatically timestamped and made available to the project's analysis pipeline via Collect.

This class deliberately does not implement Unity's OnTriggerEnter or OnTriggerExit. Each subclass is responsible for defining those callbacks according to its own requirements — whether that means applying filter logic (tag checks, layer masks, distance tests, etc.) before forwarding to Collider) / Collider), or bypassing physics callbacks entirely and invoking those methods manually from external code or a UnityEvent. Both trigger methods check enabled before firing, meaning the trigger can be enabled/disabled during runtime.

Implementing IDataLoggable opts this component into automatic discovery by the nearest ancestor DataCollector in the scene hierarchy. The collector calls Collect at regular analysis intervals; the method returns a snapshot copy of all events recorded since the last collection and resets the internal cache, so each analysis window receives exactly the events that occurred within it.

Fields

_onEnterTriggered

The UnityEvent invoked when a collider enters the trigger zone and passes all filter conditions defined by the concrete subclass.

[Header("EVENTS")]
[Tooltip("Called when a collider enters and passes the filter conditions.")]
[SerializeField]
protected UnityEvent<Collider> _onEnterTriggered

Field Value

UnityEvent<Collider>

_onExitTriggered

The UnityEvent invoked when a collider exits the trigger zone and passes all filter conditions defined by the concrete subclass.

[Tooltip("Called when a collider exits and passes the filter conditions.")]
[SerializeField]
protected UnityEvent<Collider> _onExitTriggered

Field Value

UnityEvent<Collider>

_onlyTriggerOnce

Whether the enter and exit events should each fire at most once over the lifetime of this component.

[Header("TRIGGER SETTINGS")]
[SerializeField]
[Tooltip("Whether the enter and exit events should each fire at most once.")]
protected bool _onlyTriggerOnce

Field Value

bool

Remarks

When true, Collider) nulls out _onEnterTriggered after the first successful invocation, and Collider) does the same to _onExitTriggered.

logCache

Runtime cache that accumulates TriggerRecord entries between successive Collect calls.

protected EventTriggerDataLog logCache

Field Value

EventTriggerDataLog

Remarks

Initialised lazily on the first logged event (see String)), so no allocation is made for trigger zones that never fire. When Collect is called, the cache is deep-copied into a new EventTriggerDataLog that is handed off to the analysis pipeline, and this field is reset to null so the next collection window starts empty.

Methods

Collect()

Returns a snapshot of all trigger interactions logged since the last collection, then resets the internal cache so the next collection window starts empty.

public virtual DataLog Collect()

Returns

DataLog — A deep copy of the accumulated EventTriggerDataLog, or null if no trigger events occurred since the last call to this method.

Remarks

The snapshot is produced via the copy constructor of EventTriggerDataLog, giving the caller a stable view of the data even if new trigger events are logged on the main thread after this method returns.

Returning null when logCache is null signals to the DataCollector that this component produced no events during the last analysis window. The collector is designed to skip null returns, so no placeholder allocation is ever needed.

Start()

Intentionally empty Unity lifecycle callback required to expose the component's enabled toggle in the Unity Inspector.

protected virtual void Start()

Remarks

Unity only renders the enabled checkbox in the Inspector header for components that define at least one of the recognised message methods (Start, Update, FixedUpdate, etc.). Because BaseEventTrigger acts as a purely passive responder — no per-frame work is required — this override exists solely to satisfy that Unity requirement.

TimestampEventLog(string, string)

Appends a new timestamped record to the runtime log cache, capturing the name of the triggering object and a human-readable event-type label.

protected void TimestampEventLog(string eventType, string objName)

Parameters

Name	Type	Description
eventType	string	A short human-readable label for the event type (e.g., "Enter UnityEvent Invoked"). Stored verbatim in the TriggerRecord and appears in analysis exports.
objName	string	The resolved name of the game object whose collider triggered the event. For compound-Rigidbody actors this is the Rigidbody root's name, not the child collider's name.

Remarks

The cache is allocated lazily on the first call using the null-coalescing assignment operator (??=), so no heap allocation occurs for trigger zones that never fire. The EventTriggerDataLog is identified by this component's GameObject name.

TriggerEnterEvent(Collider)

Core dispatch method called by subclasses when an entering collider has passed all filter conditions. Logs the interaction and invokes _onEnterTriggered provided the component is enabled and the event has not already been consumed.

public virtual void TriggerEnterEvent(Collider collider)

Parameters

Name	Type	Description
collider	Collider	The collider that entered the trigger zone, as provided by Unity's OnTriggerEnter callback. May be null when the method is invoked programmatically (e.g., from a test harness or editor tool) rather than by a physics event.

Remarks

Subclasses call this method from within UnityEvent such as OnTriggerEnter, which Unity fires regardless of the component's enabled state. Checking enabled here means it can be deactivated mid-session (via a UnityEvent, or script).

If _onlyTriggerOnce is true, _onEnterTriggered is set to null after invocation. Subsequent calls are silently ignored because the null guard fails.

TriggerExitEvent(Collider)

Core dispatch method called by subclasses when an exiting collider has passed all filter conditions. Logs the interaction and invokes _onExitTriggered provided the component is enabled and the event has not already been consumed.

public virtual void TriggerExitEvent(Collider collider)

Parameters

Name	Type	Description
collider	Collider	The collider that exited the trigger zone, as provided by Unity's OnTriggerExit callback. May be null when invoked programmatically.

Remarks

Mirrors the behaviour of Collider): the enabled check allows the zone to be deactivated mid-session and the event is prevented from firing more than once when _onlyTriggerOnce is true.