# World event dispatch

**URL:** <https://forum.8thwall.com/t/world-event-dispatch/2629>\
**Category:** Technical Support\
**Tags:** general\
**Created:** [September 3, 2024, 9:23am UTC](https://forum.8thwall.com/t/world-event-dispatch/2629 "2024-09-03T09:23:12Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![Wonderment\_by\_Design](https://avatars.discourse-cdn.com/v4/letter/w/77aa72/32.png) [@Wonderment\_by\_Design](https://forum.8thwall.com/u/Wonderment_by_Design)\
**Post date:** [September 3, 2024, 9:23am UTC](https://forum.8thwall.com/t/world-event-dispatch/2629/1 "2024-09-03T09:23:12Z")

</div>

Hello everyone. I’m working on a project in 8th wall. I’ve followed quite a few tutorials and gone through quite a few of the sample projects. I cannot seem to figure out how to properly use world events and dispatch to them.

```auto
import * as ecs from '@8thwall/ecs'
import {ClayPigeon} from './clayPigeon'
import {MouseButtons, MouseEvents} from './mouseControls'
const {THREE} = (window as any)

ecs.registerComponent({
  name: 'GameManager',
  schema: {
    shotsTakenDisplay: ecs.eid,
    shotsHitDisplay: ecs.eid,
    clayPigeonEntity: ecs.eid,
  },
  data: {
    score: ecs.i32,
    shotsTaken: ecs.i32,
    pigeon: ecs.eid,
  },
  add: (world, component) => {
    const {shotsTakenDisplay, clayPigeonEntity} = component.schema
    if (!clayPigeonEntity) {
      console.log('no pigeon entity')
    }

    function handleInteraction(event) {
      const raycaster = new THREE.Raycaster()
      const castPoint = new THREE.Vector2()
      castPoint.x = 0
      castPoint.y = 0
      raycaster.setFromCamera(castPoint, world.three.activeCamera)
      const pigeon = world.three.entityToObject.get(clayPigeonEntity)
      if (!pigeon) {
        console.error('Ground object not found for entity ID:', pigeon)
        return
      }
      // C is not a function?
      world.events.dispatch(world.events.globalId, 'shoot', this)
      const intersects = raycaster.intersectObject(pigeon, true)
      if (intersects.length > 0) {
        console.log('hit pigeon')
        world.events.dispatch(world.events.globalId, 'hitShot', this)
      }
    }
    window.addEventListener('click', handleInteraction)
  },

  stateMachine: ({world, eid, schemaAttribute, dataAttribute}) => {
    const shoot = () => {
      console.log('shoot')
      const data = dataAttribute.acquire(eid)
      data.score += 1
      ecs.Ui.set(world, schemaAttribute.get(eid).shotsTakenDisplay, {
        text: data.score.toString(),
      })
      dataAttribute.commit(eid)
    }
    const hitShot = () => {
      console.log('hit shot')
      const data = dataAttribute.acquire(eid)
      data.shotsTaken += 1
      ecs.Ui.set(world, schemaAttribute.get(eid).shotsTakenDisplay, {
        text: data.shotsTaken.toString(),
      })
      dataAttribute.commit(eid)
    }
    ecs.defineState('default').initial().onEnter(() => {
      world.events.addListener(world.events.globalId, 'shoot', this)
      world.events.addListener(world.events.globalId, 'hitShot', this)
    }).onExit(() => {
      world.events.removeListener(world.events.globalId, 'shoot', this)
      world.events.removeListener(world.events.globalId, 'hitShot', this)
    })
  },

})

```

This is my game manager class. I basically have two different events that I want to fire through the world event dispatcher. All they do right now is they should increment a score display on the screen.

However, when I try to fire any of these world events through world.events.dispatch, the editor throws an error: TypeError: C is not a function.

Any guidance as to what I’m doing wrong would be greatly appreciated.

I got the setup of this class from [(6) Niantic Studio Workshop: Game Mechanics Basics - YouTube](https://www.youtube.com/watch?v=ldWcksOfIYs&t=1404s) this workshop.

---

<div class="post-metadata">

**Author:** ![GeorgeButler](https://sea1.discourse-cdn.com/flex019/user_avatar/forum.8thwall.com/georgebutler/32/1903_2.png) [@GeorgeButler](https://forum.8thwall.com/u/GeorgeButler)\
**Post date:** [September 3, 2024, 4:31pm UTC](https://forum.8thwall.com/t/world-event-dispatch/2629/2 "2024-09-03T16:31:26Z")

</div>

Your event dispatcher’s third argument should be an object with the data you want to send through the event. You can find more details in this [guide](https://www.8thwall.com/docs/studio/guides/events/#dispatch-listener-example).

For example, you might use something like this:

```javascript
world.events.dispatch(world.events.globalId, 'shoot', {shooter: this})

```

However, I’m not certain if non-primitive data is supported when dispatching events. To be safe, I’d recommend sticking to primitive types rather than passing something like `this`. Here’s more information on [primitive types](https://developer.mozilla.org/en-US/docs/Glossary/Primitive).

---

<div class="post-metadata">

**Author:** ![Wonderment\_by\_Design](https://avatars.discourse-cdn.com/v4/letter/w/77aa72/32.png) [@Wonderment\_by\_Design](https://forum.8thwall.com/u/Wonderment_by_Design)\
**Post date:** [September 4, 2024, 9:52am UTC](https://forum.8thwall.com/t/world-event-dispatch/2629/3 "2024-09-04T09:52:11Z")

</div>

I’ve solved this on my own merrit.

```auto
ecs.defineState('default').initial().onEnter(() => {
      world.events.addListener(world.events.globalId, 'shoot', shoot)
      world.events.addListener(world.events.globalId, 'hitShot', hitShot)
    }).onExit(() => {
      world.events.removeListener(world.events.globalId, 'shoot', shoot)
      world.events.removeListener(world.events.globalId, 'hitShot', hitShot)
    })

```

I was formatting the expression wrong. The tooltips in the editor are rather ambigious so it took some trial and error.

---

<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/flex019/uploads/x8thwall/original/2X/9/9212a857458f1b03a6accb129e0f8cbea408e3e5.png) [@system](https://forum.8thwall.com/u/system)\
**Post date:** [September 8, 2024, 9:52am UTC](https://forum.8thwall.com/t/world-event-dispatch/2629/4 "2024-09-08T09:52:20Z")

</div>

Closed on September 8, 2024, 9:52am UTC

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