Hey all, I was just wondering if anyone had any idea why this shader doesn't work for mobile. The specific line that has problems is : col = lerp(col, c, 0.5);

Whenever it is set to 0 or 1 it will work, however any values in between don't seem to function properly and give me a pink terrain with the error "no subshaders can run on this graphics card"

I am attempting to write the shader for the Android platform at the moment. I haven't ever really done shader programming, so I apologize if it looks horrid.

     Shader "Fog Of War/Terrain" {
         Properties {
             _FOWTex ("Detail", 2D) = "gray" {}
             
             // Textures
                 _Control ("Control (RGBA)", 2D) = "white" {}
             _Splat3 ("Layer 3 (A)", 2D) = "white" {}
             _Splat2 ("Layer 2 (B)", 2D) = "white" {}
             _Splat1 ("Layer 1 (G)", 2D) = "white" {}
             _Splat0 ("Layer 0 (R)", 2D) = "white" {}
         
         }
         SubShader {
             Tags { 
                     "RenderType"="Opaque" 
                     "Queue" = "Geometry-100"
                     "SplatCount" = "4"
                 }
             CGPROGRAM
             #pragma surface surf Lambert
             #pragma target 3.0
             
             #include "UnityCG.cginc"
             
             struct Input {
                 float2 uv_FOWTex;
                 float2 uv_Control : TEXCOORD0;
                 float2 uv_Splat0 : TEXCOORD1;
                 float2 uv_Splat1 : TEXCOORD2;
                 float2 uv_Splat2 : TEXCOORD3;
                 float2 uv_Splat3 : TEXCOORD4;
             };
             
             sampler2D _FOWTex;
             sampler2D _Control;
             sampler2D _Splat0,_Splat1,_Splat2,_Splat3;
             
             void surf (Input IN, inout SurfaceOutput o) {
                 fixed4 splat_control = tex2D (_Control, IN.uv_Control).rgba;
                 float4 col;
                 float4 c;
                 
                 col  = splat_control.r * tex2D (_Splat0, IN.uv_Splat0);
                 col += splat_control.g * tex2D (_Splat1, IN.uv_Splat1);
                 col += splat_control.b * tex2D (_Splat2, IN.uv_Splat2);
                 col += splat_control.a * tex2D (_Splat3, IN.uv_Splat3);
                 c     = tex2D (_FOWTex, IN.uv_FOWTex).aaaa;
                 col = lerp(col, c, 0.5);
                 o.Albedo = col;
                 o.Alpha = 0.0;
             }
             
             ENDCG
         } 
         Dependency "AddPassShader" = "MyShaders/Terrain/Editor/AddPass"
         Dependency "BaseMapShader" = "MyShaders/Terrain/Editor/BaseMap"
     }