Shader "Custom/GreyscaleShader"
{
	HLSLINCLUDE
#include "Packages/com.unity.postprocessing/PostProcessing/Shaders/StdLib.hlsl"

		TEXTURE2D_SAMPLER2D(_MainTex, sampler_MainTex);
	float _Blend;

	float4 Frag(VaryingsDefault i) :SV_Target
	{
		float4 color = SAMPLE_TEXTURE2D(_MainTex, sampler_MainTex, i.texcoord);
		float luminance = dot(color.rgb, float3(0.2126729, 0.7151522, 0.0721750));
		color.rgb = lerp(color.rgb, luminance.xxx, _Blend.xxx);
		return color;
	}
	ENDHLSL
    SubShader
    {
		Cull Off
		ZWrite Off
		ZTest Always

		Pass{
			HLSLPROGRAM

				#pragma vertex VertDefault
				#pragma fragment Frag

			ENDHLSL
		}
    }
}