# Get started

Build an Event that launches a cube when you click it. You'll create a scene and configure the behavior in Unity without writing code.

![Example of launching a cube when clicking it](assets/example-get-started.mp4 "autoplay")

## Step 1: Build the scene

Create two Unity primitives:

1. Add the ground with `GameObject` → `3D Object` → `Plane`. Leave it at the origin.
2. Add the cube with `GameObject` → `3D Object` → `Cube`, and set its **Position** to `(0, 1, 0)` so it sits floating above the plane.

![Plane and cube in the scene](assets/example-scene.jpg)

!!! info "Unity primitives include colliders"
    Unity's primitives come with a collider attached. Physics needs the collider so the cube lands on the floor instead of falling through it. Mouse Triggers need it so the pointer has something to hit.

## Step 2: Make the cube physical

Select `Cube`, click **Add Component**, and add a **Rigidbody**.

Press **Play**. The Rigidbody makes the cube drop and land on the plane, which provides a physical object for the Event to move.

Stop Play mode before continuing.

## Step 3: Create the Event object

Create an empty game object with `GameObject` → `Create Empty` and name it `Launcher`.

Select it, click **Add Component**, and choose `Visual Script` → `Event`.

The component appears with two empty lists: **Triggers** at the top, and **Instructions** below.

* The **Triggers** list defines when the Event runs.
* The **Instructions** list defines what the Event does.

![Example of an empty Event component](assets/example-event-empty.jpg)

!!! tip "The Event doesn't have to live on the cube"
    This Event lives on a separate, empty object. An Event doesn't need to be attached to the object it affects.

    This separation lets one manager object drive several props and keeps shared logic in one place.

## Step 4: Add the Trigger

Click the **+** button under **Triggers**. A search window opens with the available Triggers.

Type `mouse click` and pick **On Mouse Click**. It fires when a mouse button is pressed and released over the same collider.

The Trigger initially watches `Launcher`, which has no collider, so it can't detect a mouse click. Point it at the cube:

1. Open the Trigger's object field dropdown.
2. Choose **Rigidbody**, under `Components` → `Physics 3D`.
3. Drag `Cube` from the Hierarchy into the field that appears.

![Example of Event with trigger and empty instructions](assets/example-event-trigger.jpg)

The Trigger line now reads **On Cube Mouse Click**.

!!! info "The Rigidbody source resolves its game object"
    The dropdown offers several ways to identify an object, including its name, tag, or position in the hierarchy. With **Rigidbody**, you assign the component and Visual Script resolves the game object that owns it.

    This source accepts only objects with a Rigidbody, which prevents assigning an incompatible object.

    **Game Object**, at the top of the same dropdown, takes the object itself and finds its Rigidbody through an internal cache. Use either source for this example.

## Step 5: Add the Instruction

Click the **+** button under **Instructions**, type `add force` and pick **Rigidbody Add Force**, under `Physics 3D` → `Rigidbody`.

It has three fields:

| Field | Set it to |
| :--- | :--- |
| **Rigidbody** | Drag `Cube` in, the same way as before. |
| **Force** | `(8, 2, 0)` |
| **Mode** | **Impulse** |

![Example of Event with trigger and instruction](assets/example-event.jpg)

The force combines direction and strength. A Y value of `2` pushes the cube upward, while an X value of `8` pushes it along the positive X axis. The Z value of `0` adds no force along the Z axis.

!!! info "Impulse applies the whole push at once"
    Use **Force** for a push applied over successive physics steps, such as a rocket engine or constant wind. **Impulse** applies a push at once, as with a kick, bullet hit, or explosion.

    Use **Impulse** for this single shove. Switching to **Force** produces much less movement because Unity applies the same values across one physics step.

## Step 6: Play

Press **Play**, then click the cube **in the Game view**.

It launches up and to the right, tumbles, and comes to rest. Click it again to send it further.

![Example of launching a cube when clicking it](assets/example-get-started.mp4)

!!! warning "Clicking in the Scene view does nothing"
    Mouse Triggers use Unity's pointer messages, which only fire in the **Game** view. If nothing happens, check that you're clicking the cube in that view.

## What the Event does

The `Launcher` object now holds an Event with one Trigger and one Instruction. Read it from top to bottom in the Inspector:

*On Cube Mouse Click* → *Cube Add Force ((8, 2, 0), Impulse)*.

Every Trigger and Instruction describes itself in one line. This makes the Event readable without opening each field.

The Event waits until the Trigger fires, then runs its Instructions from top to bottom. Add another Instruction to extend what happens after each click.

## Try it

- **Change the direction.** Set the force to `(2, 8, 0)` so the cube moves upward more than sideways.
- **Add a second Instruction.** Put **Debug Log Text** below the force and confirm both Instructions run in order.
- **Add a delay.** Put **Wait for Seconds** with a duration of `1` above the force.
- **Add a Condition.** Wrap the force in an **If** with **Rigidbody Is Sleeping** so clicks have no effect while the cube is moving.
- **Duplicate the cube.** The Event still affects the original because it holds a direct reference. [Source & Target](events/source-target.md) explains how one Event can act on whichever cube was clicked.

## Where to go next

- **[Event component](events/index.md)** — understand the execution model behind the Event you built.
- **[Example scenes](installation.md#installing-the-examples)** — inspect one complete project for each introductory behavior.
- **[Conditions](events/conditions.md)** — add yes-or-no checks to an Event.