Hole.shader

Shader "Unlit/Hole"
{
    Properties
    {
   [HDR]_Color("Color",Color) = (1,1,1,0.5)
        _MainTex ("Texture", 2D) = "white" {}
    }
    SubShader
    {
      Tags { "RenderType" = "Opaque" "Queue" = "Geometry+2"}
        ColorMask RGB

              ZTest off
            ZWrite On
            Cull Front
            Lighting Off


            Stencil
            {
                Ref 1
                Comp equal
                Pass zero
                fail zero
                zfail zero
            }

        Pass
        {
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            // make fog work
            #pragma multi_compile_fog

            #include "UnityCG.cginc"

            struct appdata
            {
                float4 vertex : POSITION;
                float2 uv : TEXCOORD0;
            };

            struct v2f
            {
                float2 uv : TEXCOORD0;
                UNITY_FOG_COORDS(1)
                float4 vertex : SV_POSITION;
            };

            sampler2D _MainTex;
            float4 _MainTex_ST;
            float4 _Color;

            v2f vert (appdata v)
            {
                v2f o;
                o.vertex = UnityObjectToClipPos(v.vertex);
                o.uv = TRANSFORM_TEX(v.uv, _MainTex);
                UNITY_TRANSFER_FOG(o,o.vertex);
                return o;
            }

            fixed4 frag (v2f i) : SV_Target
            {
                // sample the texture
                fixed4 col = tex2D(_MainTex, i.uv);
                // apply fog
                UNITY_APPLY_FOG(i.fogCoord, col);
                return col * _Color;
            }
            ENDCG
        }
    }
}