Fresnel.shader

Shader "ShaderDrill/0327/Fresnel"
{
	Properties
	{
		_MainTex ("Base (RGB) Trans (A)", 2D) = "white" {}
		_Color ("Tint", Color) = (1,1,1,1)
		_FresnelColor ("Fresnel Color", Color) = (1,1,1,1)
		_FresnelBias ("Fresnel Bias", Float) = 0
		_FresnelScale ("Fresnel Scale", Float) = 1
		_FresnelPower ("Fresnel Power", Float) = 1
	}

	SubShader
	{
		Tags
		{
			"Queue"="Geometry"
			"IgnoreProjector"="True"
			"RenderType"="Opaque"
		}

		Cull Back

		Pass
		{
			CGPROGRAM
			#pragma vertex vert
			#pragma fragment frag
			#pragma target 2.0

			#include "UnityCG.cginc"

			struct appdata_t
			{
				float4 pos : POSITION;
				float2 uv : TEXCOORD0;
				half3 normal : NORMAL;
			};

			struct v2f
			{
				float4 pos : SV_POSITION;
				half2 uv : TEXCOORD0;
				float fresnel : TEXCOORD1;
			};

			sampler2D _MainTex;
			float4 _MainTex_ST;
			fixed4 _Color;
			fixed4 _FresnelColor;
			fixed _FresnelBias;
			fixed _FresnelScale;
			fixed _FresnelPower;

			v2f vert(appdata_t v)
			{
				v2f o;
				o.pos = UnityObjectToClipPos(v.pos);
				o.uv = TRANSFORM_TEX(v.uv, _MainTex);

				float3 i = normalize(ObjSpaceViewDir(v.pos));
				o.fresnel = _FresnelBias + _FresnelScale * pow(1 + dot(i, v.normal), _FresnelPower);
				return o;
			}

			fixed4 frag(v2f i) : SV_Target
			{
				fixed4 c = tex2D(_MainTex, i.uv) * _Color;
                return lerp(c, _FresnelColor, 1 - i.fresnel);
			}
			ENDCG
		}
	}
}