Custom Fog of War

[Hazardio]

Hi everyone!

I’m actually searching for an advanced fog of war feature. I searched for days but as I am not an expert in shader programming, it’s very difficult for me to find what I want (and even more to understand how)…

So, I’m searching for a fog that hides only specific elements (instead of everything until now), so that the background remains always visible:

Actually, I already have a fog of war, wich is a plane, placed over the entire scene. It has a shader that displays as many visibility zones as necessary, it also darkens the background but the coins behind are visible.

Here is my shader:

Shader "FogOfWarShader" {
    Properties {
        _Color("Color", Color) = (1,1,1,1)
        _MainTex("Base (RGB) Trans (A)", 2D) = "white" {}
        FogMaxRadius("FogMaxRadius", Float) = 0.5
    }

    SubShader {
        Tags {"Queue" = "Transparent+500" "IgnoreProjector" = "True" "RenderType" = "Transparent+500"}
        LOD 200
        Blend SrcAlpha OneMinusSrcAlpha
        Cull Off

        CGPROGRAM
        #pragma surface surf Lambert vertex:vert alpha:blend

        sampler2D   _MainTex;
        fixed4      _Color;
        float       FogRadius[30];
        float       FogMaxRadius;
        int         NumberOfZone = 0;
        float4      VisibilityZones[30];

        struct Input {
            float2 uv_MainTex;
            float2 location;
        };

        float powerForPos(float4 pos, float radius, float2 nearVertex);

        void vert(inout appdata_full vertexData, out Input outData) {
            float4 pos = UnityObjectToClipPos(vertexData.vertex);
            float4 posWorld = mul(unity_ObjectToWorld, vertexData.vertex);
            outData.uv_MainTex = vertexData.texcoord;
            outData.location = posWorld.xz;
        }

        void surf(Input IN, inout SurfaceOutput o) {
            fixed4 baseColor = tex2D(_MainTex, IN.uv_MainTex) * _Color;

            float alpha = 1.0 - baseColor.a;
            for (int i = 0; i < NumberOfZone; i++)
            {
                alpha -= powerForPos(VisibilityZones[i], FogRadius[i], IN.location);
            }
            o.Albedo = baseColor.rgb;
            o.Alpha = alpha;
        }

        //return 0 if (pos - nearVertex) > _FogRadius
        float powerForPos(float4 pos, float radius, float2 nearVertex)
        {
            float atten = clamp(radius - length(pos.xz - nearVertex.xy), 0.0, radius);

            return (1.0 / FogMaxRadius) * atten / radius;
        }
        ENDCG
    }
    Fallback "Transparent/VertexLit"
}

I’ve seen some logic to do with different cameras but I don’t understand how to make it:

Only render part of object inside a circle

Unity seems to finally support stencil operations in custom shaders. This simplifies the implementation of such fancy things. One approach would be: render your background render your mask geometry to the stencil buffer and increase the buffer value use a custom depthmask shader which only renders where the stencil buffer is 0. Render a fullscreen quad to mask everything out except the area that the mask geometry occupies. render your second camera which should render everything that should b…

I’ve also found this that might help:

doomlaser/DepthMask-Unity-Shader/blob/master/DepthMask.shader

PS: I don’t use URP, only Basic Pipeline.
PS2: I don’t want a SphereCast where elements appears and disappears on the map according to the visibility zones positions. I want a smooth transition.

Can someone help me?

[CodeSmile]

Have you searched in the asset store?