Suspend script until keypress

Hey there, I’ve been playing around with this script from here:

I’m using the following script in a test environment.

using UnityEngine;
using System.Collections;

public class DayNightController : MonoBehaviour {

    // The directional light which we manipulate as our sun.
    public Light sun;

    // The number of real-world seconds in one full game day.
    // Set this to 86400 for a 24-hour realtime day.
    public float secondsInFullDay = 120f;

    // The value we use to calculate the current time of day.
    // Goes from 0 (midnight) through 0.25 (sunrise), 0.5 (midday), 0.75 (sunset) to 1 (midnight).
    // We define ourself what value the sunrise sunrise should be etc., but I thought these 
    // values fit well. And now much of the script are hardcoded to these values.
    public float currentTimeOfDay = 0;

    // A multiplier other scripts can use to speed up and slow down the passing of time.
    public float timeMultiplier = 1f;

    // Get the initial intensity of the sun so we remember it.
    float sunInitialIntensity;
    void Start() {
        sunInitialIntensity = sun.intensity;

    void Update() {
        // Updates the sun's rotation and intensity according to the current time of day.

        // This makes currentTimeOfDay go from 0 to 1 in the number of seconds we've specified.
        currentTimeOfDay += (Time.deltaTime / secondsInFullDay) * timeMultiplier;

        // If currentTimeOfDay is 1 (midnight) set it to 0 again so we start a new day.
        if (currentTimeOfDay >= 1) {
            currentTimeOfDay = 0;

    void UpdateSun() {
        // Rotate the sun 360 degrees around the x-axis according to the current time of day.
        // We subtract 90 degrees from this to make the sun rise at 0.25 instead of 0.
        // I just found that easier to work with.
        // The y-axis determines where on the horizon the sun will rise and set.
        // The z-axis does nothing.
        sun.transform.localRotation = Quaternion.Euler((currentTimeOfDay * 360f) - 90, 170, 0);

        // The following determines the sun's intensity according to current time of day.
        // You'll notice I have hardcoded a bunch of values here. They were just the values
        // I felt worked best. This can obviously be made to be user configurable.
        // Also with some more clever code you can have different lengths for the day and
        // night as well.

        // The sun is full intensity during the day.
        float intensityMultiplier = 1;
        // Set intensity to 0 during the night night.
        if (currentTimeOfDay <= 0.23f || currentTimeOfDay >= 0.75f) {
            intensityMultiplier = 0;
        // Fade in the sun when it rises.
        else if (currentTimeOfDay <= 0.25f) {
            // 0.02 is the amount of time between sunrise and the time we start fading out
            // the intensity (0.25 - 0.23). By dividing 1 by that value we we get get 50.
            // This tells us that we have to fade in the intensity 50 times faster than the
            // time is passing to be able to go from 0 to 1 intensity in the same amount of
            // time as the currentTimeOfDay variable goes from 0.23 to 0.25. That way we get
            // a perfect fade.
            intensityMultiplier = Mathf.Clamp01((currentTimeOfDay - 0.23f) * (1 / 0.02f));
        // And fade it out when it sets.
        else if (currentTimeOfDay >= 0.73f) {
            intensityMultiplier = Mathf.Clamp01(1 - ((currentTimeOfDay - 0.73f) * (1 / 0.02f)));

        // Multiply the intensity of the sun according to the time of day.
        sun.intensity = sunInitialIntensity * intensityMultiplier;

How could I suspend this script so that it will only start after a keypress?

At the moment, the moment the scene starts the script will start. How would I make this so the sun will only start revolving after the user has input a keypress?

Thanks for your time :smiley:

You could use the enabled property that every monobehaviour has. When it is false, Update won’t be called.

This is how you could implement it using Start as a Coroutine:

using UnityEngine;
using System.Collections;

public class Waiting : MonoBehaviour
	private IEnumerator Start()
        this.enabled = false; // Disable us while waiting

        // Wait for input
        while (!Input.anyKey)
            yield return null;

        this.enabled = true; // Enable us now

	void Update ()

In the first line of your Update() function you could write something like:

if(Input.GetKeyDown(KeyCode.Enter)) startRotating = true;
if(!startRotating) return;

and have bool startRotating = false; at the top.