Change material during runtime?

Questions & Answers
1

I’ve been working on a small game that could be described as a bit of a crossover between Pacman and Flower.
What I want to do is that as the player drives past buildings in the environment, said buildings light up. What I’ve been doing until now is that I replaced the prefabs, but this doesn’t seem to be a particularly efficient way of doing so.
So what I tried to do after that was to change the Emission parameter through code, something that Unity doesn’t seem to support particularly well.
So another idea I have now is to swap out the material entirely. But yet again, I don’t know how to do so.

My code looks as follows:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class IlluminScript : MonoBehaviour {
	public Material LitMaterial;
	// Use this for initialization
	void Start () {
		
	}
	void OnTriggerEnter(Collider col) {
	if (col.gameObject.CompareTag ("ActiveZone")) {


	}
}
	// Update is called once per frame
	void Update () {
		
	}
}
2

If you want to replace the Material on a Mesh (3D Model), you can get the MeshRenderer component from your object, and provide a new material in your OnTriggerEnter callback:

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour {
    public Material material1;
    public Renderer rend;
    void Start() {
        rend = GetComponent<Renderer>();
    }
    void Update() {
        if (Input.GetButtonDown("Jump"))
                rend.material = material1;
    }
}
3

Try this extension method

public static void ChangeMaterial(this GameObject go, Material mat)
{
    go.renderer.material = mat;
}

Then you can call it by using

if(hit.collider.gameObject.tag == "Colour1")
{
     hit.gameObject.renderer.material.ChangeMaterial( Your Material );
}

Here is another extension method for changing the color

public static void ChangeColor(this Material mat, Color color)
{
    mat.SetColor("_Color", color);      
}

method that supports multi materials on the gameObject

public static void ChangeColor(this GameObject go, Color color)
{
    if(go.GetComponent<MeshRenderer>())
    {               
        Material[] materials = go.gameObject.renderer.materials;

        foreach(Material m in materials)
        {
            m.SetColor("_Color", color);
        }   
    }
}

Finally to be more specific to your problem here is one final function for you

 public static void ChangeColor(GameObject[] gameObjects, Color color)
{
    foreach(GameObject gameObject in GameObjects)
    {
    gameObject.renderer.material.ChangeColor( "Your Color" );
   }
}

then you can call it like this:

if(hit.collider.gameObject.tag == "Colour1")
{
    GameObject[] _Colums = GameObject.FindGameObjectsWithTag("column");
    ChangeColor(_Colums, "Your Color");
}

Here the source . Hope it helps :slight_smile: