SCPE Fog integration shader example

Shader "Unlit/SCPE_TransparentWithFog"
{
    SubShader
    {
        Tags{ "RenderType" = "Transparent" "Queue" = "Transparent" }
        Blend SrcAlpha OneMinusSrcAlpha, One OneMinusSrcAlpha
        Cull Back
        Zwrite Off

        Pass
        {
            HLSLPROGRAM
            #pragma vertex vert
            #pragma fragment frag

            //Uncomment to disable features that definitely aren't used for a performance gain

            //#define DISABLE_FOG_GRADIENT
            //#define DISABLE_FOG_SKYBOXCOLOR
            //#define DISABLE_FOG_HEIGHTNOISE
            //#define DISABLE_FOG_DIRECTIONAL_COLOR

            //Source for the "ComputeFog" function and all its dependencies
            #include "Assets/SC Post Effects/Runtime/Fog/Fog.hlsl"

            struct appdata
            {
                float4 vertex : POSITION;
            };

            struct v2f
            {
                float4 vertex : SV_POSITION;
                float3 positionWS: TEXCOORD1;
                float4 screenPos : TEXCOORD2;
            };

            v2f vert (appdata v)
            {
                v2f o;
                o.vertex = UnityObjectToClipPos(v.vertex);
                o.positionWS = mul(unity_ObjectToWorld, v.vertex).xyz;
                o.screenPos = ComputeScreenPos(v.vertex);

                return o;
            }

            float4 frag (v2f i) : SV_Target
            {
                float4 col = float4(0,0,0,1);

                //The screen position input is used when the fog color source is set to "Skybox". If never in use, you can set it to 0
                float4 fogColor = ComputeTransparentFog(i.positionWS, i.screenPos);

                //The alpha channel will hold the density of the fog, use it as a lerp factor
                col.rgb = lerp(fogColor.rgb, col.rgb, fogColor.a);

                //Alternatively, apply this function also does the lerp operation
                //ApplyTransparencyFog(i.positionWS, i.screenPos, col.rgb);

                return col;
            }

            ENDHLSL
        }
    }
}