How to change the radius of a light from a script?

Unity Engine
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1

Hello,

I’m a beginner to Unity. Like, watched-my-first-tutorial-last-week beginner.

I’ve actually been doing decently well so far but I’m a bit stuck and I couldn’t find the answer anywhere in the Unity Docs:

How could I change the outer radius of the 2D light on an object within a MonoBehaviour Script? I need some light to illuminate a surface only when the emitting object is inside the surface so I want to change the light’s radius as the object enters to create a nice transition.

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This is my code with the obviously incorrect attempt to change the outer radius of the light. I tried using the syntax for the transform changes as a reference but couldn’t get it exactly.

I’m in the most recent version of Unity.

2

Code didn’t upload, let me try again:

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image418×282 9 KB

3

So the 2d light is part of the URP package, and belongs to the namespace UnityEngine.Rendering.Universal: Class Light2D | Universal Render Pipeline | 17.5.0

So up where you have using UnityEngine; you will also need to add using UnityEngine.Rendering.Universal; on another line.

And the property to change would be Light2D.pointLightOuterRadius.

Please post code as text with code tags, not as images.

4

Thank you for the help, and sorry for the late-ish reply. I unfortunately ran into another error while testing:

using UnityEngine;
using UnityEngine.Rendering.Universal;

public class ManageSpecialBulletLight : MonoBehaviour
{
	
	public float maxRadius;
	
    // Update is called once per frame
    void Update()
    {
		GameObject.Light2D.pointLightOuterRadius = maxRadius;
    }
}

image

This is the inspector window for my object I’m applying this code to:

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I assume “does not contain a definition for Light2D” means it couldn’t find the Light2D component of the object? Which doesn’t make sense to me, since I added the universal rendering reference at the top and attached the script to an object with the Light 2D.

I checked through the Hierarchy window and as far as I can tell, only that object contains my script, so it shouldn’t be trying to run on an object without Light 2D.

5

It’s not a static property. You need a reference to an instance of a Light2D object. So reference the light via the inspector and access it correctly:

using UnityEngine;
using UnityEngine.Rendering.Universal;

public class ManageSpecialBulletLight : MonoBehaviour
{
	public float maxRadius;
	
	public Light2D light;
	
    private void Update()
    {
		light.pointLightOuterRadius = maxRadius;
    }
}
6

Worked, thank you! I had forgotten about referencing objects.