Unity outline shader for 3D objects

Shader "3D Shaders/Outline Shader" {
	Properties {
		_Color ("Color", Color) = (1,1,1,1)
		_MainTex ("Albedo (RGB)", 2D) = "white" {}
		_RampTex("Ramp", 2D) = "white" {}
		_Brightness("Brightness", Range(-.5,.5)) = .5
		_RimColor("Rim Color", Color) = (0.26,0.19,0.16,0.0)
		_RimPower("Rim Power", Range(0.5, 8.0)) = 3.0

		// Value to determine if outlining is enabled and outline color + size.
		[PerRendererData] _OutlineColor("Outline Color", Color) = (1,1,1,1)
		[PerRendererData] _OutlineSize("Outline Size", float) = 0
	}	

	SubShader {
		Tags { "RenderType"="Opaque" }
		LOD 200

		 Pass
        {
            Cull Front
            ZWrite On
            CGPROGRAM
			#include "UnityCG.cginc"
			#pragma fragmentoption ARB_precision_hint_fastest
			#pragma glsl_no_auto_normalization
            #pragma vertex vert
 			#pragma fragment frag
			
            struct appdata_t 
            {
				float4 vertex : POSITION;
				float3 normal : NORMAL;
			};

			struct v2f 
			{
				float4 pos : SV_POSITION;
			};

            fixed _OutlineSize;
			fixed4 _OutlineColor;

            
            v2f vert (appdata_t v) 
            {
                v2f o;
			    o.pos = v.vertex;
			    o.pos.xyz += normalize(v.normal.xyz) *_OutlineSize * 0.01;
			    o.pos = UnityObjectToClipPos(o.pos);
			    return o;
            }
           
            fixed4 frag(v2f i) :COLOR 
			{
		    	return _OutlineColor;
			}
            
            ENDCG
        }
		
		CGPROGRAM
		// Physically based Standard lighting model, and enable shadows on all light types
		#pragma surface surf Toon

		// Use shader model 3.0 target, to get nicer looking lighting
		#pragma target 3.0
		
		sampler2D _MainTex;
		sampler2D _RampTex;
		fixed4 _Color;
		fixed _Brightness;
		fixed4 _RimColor;
		fixed _RimPower;

		half4 LightingToon(SurfaceOutput s, half3 lightDir, half atten)
		{
			half NdotL = dot(s.Normal, lightDir);
			NdotL = tex2D(_RampTex, fixed2(NdotL, 0.5));

			fixed4 c;
			c.rgb = s.Albedo * _LightColor0.rgb * NdotL * atten;
			c.a = s.Alpha;
			return c;
		}

		struct Input {
			float2 uv_MainTex;
			float3 viewDir;
		};

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

			o.Emission = _Brightness;

			half rim = 1.0 - saturate(dot(normalize(IN.viewDir), o.Normal));
			o.Emission += _RimColor.rgb * pow(rim, _RimPower);

			o.Alpha = c.a;
		}
		ENDCG
	}
}