Problem with flickering ambient lighting in deferred passes

Unity Engine
,
1

Hey everybody,

I’m getting some annoying flickering using ambient light in my deferred shader. The flicker doesn’t happen normally but whenever i move the camera in scene view or inspect a gameobject with the material it flickers back and forth to no ambient lighting and with then ambient.

I think it may be because i have to use ambient within the actual internal deferred shading and not the initial buffer writing shader. I’m going for a cel shaded look, so when I go through the light passes I get the maximum of the color that’s already there and the color I want to write using BlendOp Max.

Cause of that i need to add ambient light to the light color like so:

float3 steppedLight = (steppedLightAtten*light.color) + unity_AmbientSky; // UNITY_LIGHTMODEL_AMBIENT;
Because otherwise any lights that are lower than the ambient light would be ignored.

Now there are two ways I can think of to solve this.

  1. I use my own color(s) in the properties of the deferred shader as a lookup texture. This way I’ll be able to edit it from script. Down side is it adds a little bit more complexity, and slows it down just a bit.

  2. I make a shader that goes after the final deferred light pass. This way I can use the stock ambient values without needing to add my own. I’d also be able to apply some small after effects very easily. Down side is I don’t even know if this way would work.

My problem is I don’t even know where to start to work on these solutions.

Any help to point me in the right direction, or suggesting a different approach would be appreciated!

2

I’ve solved this now and I feel dumb.
I set up a simple ambient light manager that contains the light color i want and put it on a gameobject in the scene.
The code:

[ExecuteInEditMode]
public class AmbientManager : MonoBehaviour
{
    public Color ambientColor;
    private int propertyID;
    void Start()
    {
        propertyID = Shader.PropertyToID("_AmbientColor");
    }
    void Update()
    {
        Shader.SetGlobalColor(propertyID, ambientColor);
    }
}

And I used the following inside my internal shader properties afer the gbuffer samplers:

float4 _AmbientColor;
and changed the steppedlight line to this:
float3 steppedLight = (steppedAtten*light.color)+_AmbientColor;