Shader "Hidden/ExampleScannerImage"
{
	Properties
	{
		_MainTex ("Texture", 2D) = "white" {}
		_MaskTex("Mask Texture", 2D) = "white" {}
		_MaskTexTillY("Till Y",Float) = 1.0
		_DepthParam ("DepthParam",Float) = 1.0
		_DepthColor("DepthColor",Color) = (1,1,1,1)
		_DepthLength ("DepthLength",Float) = 1.0
	}
	SubShader
	{
		// No culling or depth
		Cull Off ZWrite Off ZTest Always

		Pass
		{
			CGPROGRAM
			#pragma vertex vert
			#pragma fragment frag
			#include "UnityCG.cginc"

			sampler2D _MainTex;
			sampler2D _CameraDepthTexture;
			sampler2D _MaskTex;
			float4 _MaskTex_ST;
			float _MaskTexTillY;
			float _DepthParam;
			fixed4 _DepthColor;
			float _DepthLength;

			struct appdata
			{
				float4 vertex : POSITION;
				float2 uv : TEXCOORD0;
			};

			struct v2f
			{
				float2 uv : TEXCOORD0;
				float4 vertex : SV_POSITION;
			};

			v2f vert (appdata v)
			{
				v2f o;
				o.vertex = UnityObjectToClipPos(v.vertex);
				o.uv = v.uv;
				return o;
			}

			fixed4 frag (v2f i) : SV_Target
			{
				fixed4 mainTex = tex2D(_MainTex, i.uv);
				float depth = SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture,i.uv);
				float linearDepth = LinearEyeDepth(depth.r);
				float diff = linearDepth-_DepthParam;
				fixed4 border = 1-(saturate(floor(diff))+saturate(-diff*_DepthLength));
				
				_MaskTex_ST.y = _MaskTexTillY;
				i.uv = TRANSFORM_TEX(i.uv, _MaskTex);
				fixed4 maskTex = tex2D(_MaskTex,i.uv);

				fixed4 final = lerp(mainTex,saturate(border*_DepthColor+mainTex*_DepthColor.a+maskTex*_DepthColor),saturate(border));
				return final; 
			}
			ENDCG
		}
	}
}