"Input limit (8) exceeded" error on shader

[avoorhees]

Hey all, I’m trying to create a Fresnel shader that uses a cubemap to mask the Fresnel off from certain sections of the model. I want the Fresnel to not show up on areas that face downwards (so it kind of fakes a directional lighting effect).

Anyway, I’m getting the following errors:

Program ‘frag_surf’, error X4506: ps_4_0_level_9_3 input limit (8) exceeded, shader uses 9 inputs. (compiling for d3d11_9x) at line 16

Program ‘frag_surf’, input semantic attribute “TEXCOORD” has too big of a numeric index (8) at line 58

I know I need to reduce the number of inputs, but I’m a beginner and I don’t know how to do that.

Shader "WMS/Fresnel_Directional" {
    Properties {
      _Color ("Main Color", Color) = (1,1,1,1)
      _SpecColor ("Specular Color", Color) = (1, 1, 1, 1)
      _RimColor ("Fresnel Color", Color) = (0.26,0.19,0.16,0.0)
      _RimPower ("Fresnel Reflections", Range(0.0, 8.0)) = 3.0
      _Shininess ("Polish", Range (0.05, 5)) = 0.5
      _MainTex ("Diffuse", 2D) = "white" {}
      _SpecMap ("Specular (R) Polish (G)", 2D) = "black" {}
      _BumpMap ("Normal", 2D) = "bump" {}
      _Cube ("Cubemap", CUBE) = "" {}
    }
    SubShader {
      Tags { "RenderType" = "Opaque" }

CGPROGRAM
#pragma surface surf BlinnPhong 
#pragma target 3.0

      struct Input {
          float2 uv_MainTex, uv_BumpMap, uv_SpecMap;
          float3 worldRefl;
          float3 viewDir;
          INTERNAL_DATA
      };
      
      samplerCUBE _Cube;
      sampler2D _MainTex;
      sampler2D _BumpMap;
      sampler2D _SpecMap;
      fixed4 _Color;
      half _Shininess;
      float _RimPower;
      float4 _RimColor;
      
      void surf (Input IN, inout SurfaceOutput o) {
          fixed4 tex = tex2D(_MainTex, IN.uv_MainTex);
          fixed4 specTex = tex2D(_SpecMap, IN.uv_SpecMap);
          o.Albedo = tex.rgb * _Color;
          o.Gloss = specTex.r;
          o.Specular = _Shininess;
          o.Normal = UnpackNormal(tex2D(_BumpMap, IN.uv_BumpMap));
          half rim = 1.0 - saturate(dot (normalize(IN.viewDir), o.Normal));
		  o.Emission = _RimColor.rgb * texCUBE (_Cube, WorldReflectionVector (IN, o.Normal )) * pow (rim, _RimPower);	

      }
      ENDCG
    } 
    Fallback "Specular"
  }

[aosome23]

I think you need

#pragma exclude_renderers d3d11_9x

right after line 18 to tell unity that it is 9 times