Shader "Hidden/Bansonic/GlobalMonochrome"
{
    SubShader
    {
        Tags { "RenderPipeline" = "UniversalPipeline" }
        ZWrite Off
        Cull Off
        ZTest Always

        Pass
        {
            Name "GlobalMonochrome"

            HLSLPROGRAM
            #pragma vertex Vert
            #pragma fragment Frag
            #pragma target 4.5

            #include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/Core.hlsl"
            #include "Packages/com.unity.render-pipelines.core/Runtime/Utilities/Blit.hlsl"

            float _MonochromeIntensity;

            half4 Frag(Varyings input) : SV_Target
            {
                float2 uv = input.texcoord;
                half4 color = SAMPLE_TEXTURE2D_X(_BlitTexture, sampler_LinearClamp, uv);
                half luminance = dot(color.rgb, half3(0.299h, 0.587h, 0.114h));
                half3 grayscale = luminance.xxx;
                color.rgb = lerp(color.rgb, grayscale, saturate(_MonochromeIntensity));
                return color;
            }
            ENDHLSL
        }
    }
}