Simple struct to save and restore Unity's fog properties

FogProperties.cs

using UnityEngine;

public struct FogProperties
{
    public float EndDistance;
    public float StartDistance;
    public float Density;
    public Color Color;
    public FogMode Mode;
    public bool Enabled;

    public static FogProperties NewFromRenderSettings()
    {
        var props = new FogProperties();
        props.EndDistance = RenderSettings.fogEndDistance;
        props.StartDistance = RenderSettings.fogStartDistance;
        props.Density = RenderSettings.fogDensity;
        props.Color = RenderSettings.fogColor;
        props.Mode = RenderSettings.fogMode;
        props.Enabled = RenderSettings.fog;
        return props;
    }

    public void ApplyToRenderSettings()
    {
        RenderSettings.fogEndDistance = EndDistance;
        RenderSettings.fogStartDistance = StartDistance;
        RenderSettings.fogDensity = Density;
        RenderSettings.fogColor = Color;
        RenderSettings.fogMode = Mode;
        RenderSettings.fog = Enabled;
    }
}