Hello, Unity

Part of the Unity Scripting Basics section of Coddy's Unity journey. Lesson 1 of 85.

Everything in a Unity game is a GameObject: the ground, the player, the camera, even an invisible spawner. What a GameObject does comes from the components attached to it, and the components you write yourself are scripts.

A script is a C# class that extends MonoBehaviour. Unity runs the game and calls the script's methods for you. It calls Start() once, when the game begins, and Update() on every frame, many times a second. That is how a game moves: a tiny change in every frame.

void Start()
{
    Debug.Log("The game has started");
}

Debug.Log writes a message to the Console, the panel under the game. The script in this lesson is already finished: press Play and watch the cube come alive.

Challenge

Easy

This script is already finished: run it and see what it does.

In Start(), Debug.Log("Hello, Unity!"); writes a message in the Console once.
In Update(), two lines turn the cube and move it up and down on every frame.

Press Play: the cube spins and floats, and the Console shows Hello, Unity!. Then Check.

Try it yourself

using UnityEngine;

public class HelloUnity : MonoBehaviour
{
    public float spinSpeed = 120f;

    void Start()
    {
        Debug.Log("Hello, Unity!");
    }

    void Update()
    {
        transform.Rotate(0, spinSpeed * Time.deltaTime, 0);
        float height = 1f + Mathf.Sin(Time.time * 2f) * 0.5f;
        transform.position = new Vector3(0, height, 0);
    }
}