Change material at runtime - I must be overlooking something

Questions & Answers
1

Hi, i’m trying to have a dynamic cloud system of sorts wherein the cloud color and alpha changes depending on time of day. I have the system set up as below. I’ve looked through several posts on this topic but nothing seems to be working for me. I’m pretty sure i’m overlooking something obvious - could someone please tell me what is going wrong here?

I’m using Unity 2019.3, and URP as the renderer.

My code is as below:

public material SkyClouds;
private material cloudsMat; 

void Start()
{ 
cloudsMat = SkyClouds; 
cloudBox = GameObject.CreatePrimitive(PrimitiveType.Sphere);
cloudBox.transform.localScale = new Vector3(1000, 500, 1000);
cloudBox.GetComponent<Renderer>().material = cloudsMat; // works fine upto here, I get the initial cloud material set and visible
}

void Update()
{
cloudAlpha = 0.1f * timeofday; // I have a separate variable that controls time of day
cloudsMat.color = new color(redfactor * timeofday,1,1,cloudAlpha); //basically a calculation that changes redness and transparency depending on time of day

cloudBox.GetComponent<Renderer>().material = cloudsMat; //this is the solution I found on most posts, but it doesn't work for me. The material color or transparency does not change at all.

//I have also tried cloudBox.GetComponent<Renderer>().material.SetColor("_BaseMap", new color (1,1,1,cloudAlpha) and using materialpropertyblock, both don't work for me. What might be happening is if I look in the inspector, the game has created a separate object called "Sphere" - maybe the code does not refer to this "Sphere" object at update time? It sets the material fine at "Start", but nothing changes at "Update"//
}
2

Try accessing with

renderer.materials[0]

So it will be

renderer.materials[0].SetColor(redfactor * timeofday,1,1,cloudAlpha)
3

Thanks for your reply. It appears that I had to use “_BaseColor” instead of “_BaseMap” because of the shader I was using (URP simple lit). It’s working now.