[HDRP] Dynamically change emission value

Questions & Answers
1

Hello everyone,
I’m using the Lit shader in HDRP and I would like to control the emission value in EV100 or Nits dynamically from a script.

I have a code which reads from a 0-1 curve and then multiplies the result to a value (so I can stay in a given range of emission). The code seems to work, if I look in the material I can see the value changing. However, the object emission in the scene doesn’t change accordingly. Is that normal?

The code goes like this:

_mat.SetFloat(Shader.PropertyToID("_EmissiveIntensity"),emissionIntensityCurve.Evaluate(Time.time)*emissionMultiplier);

I tried with different values, and the emission changes if I change them manually (even in play mode) but it seems that the script is ignoring it.

2

I’m facing the same problem. The solution is to use MaterialPropertyBlock and EmissiveColor instead of material.SetFloat

public Renderer targetRenderer;
[Range(0f, 1f)]
public float emissiveIntensity = 0f;
public Color baseEmissiveColor;
     
// You may want to alter this value depending on how intense you want your emissive strength to be
private const float MaxIntensity = 30f;
 
private MaterialPropertyBlock _propBlock;
 
private void OnEnable()
{
     _propBlock = new MaterialPropertyBlock();
}
 
// Update is called once per frame
private void Update()
{
     // Get Material Property Block from Material at first index on specified Glove Renderer
     targetRenderer.GetPropertyBlock(_propBlock, 0);
 
     _propBlock.SetColor("_EmissiveColor", baseEmissiveColor * Mathf.Lerp(0f, MaxIntensity, emissiveIntensity));
 
     // Update Material on specified Glove Renderer at first index of materials
     targetRenderer.SetPropertyBlock(_propBlock, 0);
}

I found the solution here
https://forum.unity.com/threads/hdrp-shader-change-in-build-lead-to-black-material.732350/#post-6094659