LumixEngine

Triggers

Triggers are special collision shapes that detect when other objects enter or exit their area without physically blocking movement. Any rigid actor can be made a trigger by setting its Trigger property in the editor’s property grid or programmatically. They’re commonly used for:

• Detecting when a player enters a specific zone
• Activating events when objects pass through an area
• Creating invisible boundaries or checkpoints
• Implementing pickup detection for items

Evox API

Import core:physics to poll trigger events produced by the latest physics simulation step. PhysicsModule.getTriggerHits returns an iterator over TriggerHitData values:

import "core:physics"
import "core:world"

fn processTriggers(world : World) : void {
	const physics = world.physics() else return;

	for hit in physics.getTriggerHits() {
		if hit.touch_lost {
			// hit.e1 stopped overlapping hit.e2
		}
		else {
			// hit.e1 started overlapping hit.e2
		}
	}
}

hit.e1 is the entity configured as a trigger, hit.e2 is the other entity, and hit.touch_lost distinguishes exit events from enter events. Consume the events each frame; do not retain the iterator.

To enable or disable trigger behavior programmatically, use the rigid actor component:

import "core:rigid_actor"

fn setTrigger(entity : Entity, enabled : bool) : void {
	const actor = entity.rigid_actor() else return;
	actor.setIsTrigger(enabled);
}

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