Gloss.shader

Shader "BASICxSHADER/Texturing/Gloss" {
  Properties {
    _MainTex ("Main Texture", 2D) = "white" {}
    _SpecTex ("Specular Texture", 2D) = "black" {}
    _Shininess ("Shininess", Float) = 20
  }
  SubShader {
    Pass {
      Tags { "LightMode" = "ForwardBase" }

      CGPROGRAM
      #pragma vertex vert
      #pragma fragment frag

      // Properties
      uniform fixed4    _LightColor0;
      uniform sampler2D _MainTex;
      uniform float4    _MainTex_ST;
      uniform sampler2D _SpecTex;
      uniform float4    _SpecTex_ST;
      uniform half      _Shininess;

      // Vertex Input
      struct appdata {
        float4 vertex : POSITION;
        float3 normal : NORMAL;
        float2 uv     : TEXCOORD0;
      };

      // Vertex to Fragment
      struct v2f {
        float4 pos      : SV_POSITION;
        float3 normal   : NORMAL;
        float2 uv       : TEXCOORD0;
        float4 posWorld : TEXCOORD1;
      };

      //------------------------------------------------------------------------
      // Vertex Shader
      //------------------------------------------------------------------------
      v2f vert(appdata v) {
        v2f o;
        o.pos      = UnityObjectToClipPos(v.vertex);
        o.normal   = normalize(mul(v.normal, unity_WorldToObject).xyz);
        o.uv       = v.uv;
        o.posWorld = mul(unity_ObjectToWorld, v.vertex);
        return o;
      }

      //------------------------------------------------------------------------
      // Fragment Shader
      //------------------------------------------------------------------------
      fixed4 frag(v2f i) : SV_Target {
        // Vector
        half3 normal   = normalize(i.normal);
        half3 lightDir = normalize(_WorldSpaceLightPos0.xyz);
        half3 viewDir  = normalize(_WorldSpaceCameraPos.xyz - i.posWorld);
        half3 halfDir  = normalize(lightDir + viewDir);

        // Dot
        half NdotL = saturate(dot(normal, lightDir));
        half NdotH = saturate(dot(normal, halfDir));

        // Color Map
        fixed4 mainTex = tex2D(_MainTex, i.uv * _MainTex_ST.xy + _MainTex_ST.zw);
        fixed3 diffuse = _LightColor0.rgb * mainTex.rgb * NdotL;

        // Gloss Map
        fixed4 specTex  = tex2D(_SpecTex, i.uv * _SpecTex_ST.xy + _SpecTex_ST.zw);
        fixed3 specular = _LightColor0.rgb * specTex.rgb * pow(NdotH, _Shininess) * specTex.a;

        // Color
        fixed3 ambient = UNITY_LIGHTMODEL_AMBIENT.rgb * mainTex.rgb;
        fixed4 color = fixed4(ambient + diffuse + specular, 1.0);

        return color;
      }
      ENDCG
    }
  }
}