Outline shader

Shader "Custom/Outline"
{
    Properties
    {
        //[PerRendererData] _Color ("Glow Color", Color ) = ( 1, 1, 1, 1)
        _Intensity ("Intensity", Float) = 2
        [Enum(UnityEngine.Rendering.BlendMode)] _SrcBlend ("Src Blend", Float) = 1
        [Enum(UnityEngine.Rendering.BlendMode)] _DstBlend ("Dst Blend", Float) = 0
    }

    SubShader
    {
        HLSLINCLUDE

        #include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/Core.hlsl"

        struct Attributes
        {
            float4 positionOS   : POSITION;
            float2 uv           : TEXCOORD0;
        };

        struct Varyings
        {
            half4 positionCS    : SV_POSITION;
            half2 uv            : TEXCOORD0;
        };

        TEXTURE2D_X(_OutlineRenderTexture);
        SAMPLER(sampler_OutlineRenderTexture);

        TEXTURE2D_X(_OutlineBluredTexture);
        SAMPLER(sampler_OutlineBluredTexture);

        half4 _Color;
        half _Intensity;

        Varyings Vertex(Attributes input)
        {
            Varyings output;
            output.positionCS = float4(input.positionOS.xy, 0.0, 1.0);
            output.uv = input.uv;
            if (_ProjectionParams.x < 0.0)
                output.uv.y = 1.0 - output.uv.y;
            return output;
        }

        half4 Fragment(Varyings input) : SV_Target
        {
            float2 uv = UnityStereoTransformScreenSpaceTex(input.uv);
            half4 prepassColor = SAMPLE_TEXTURE2D_X(_OutlineRenderTexture, sampler_OutlineRenderTexture, uv);
            half4 bluredColor = SAMPLE_TEXTURE2D_X(_OutlineBluredTexture, sampler_OutlineBluredTexture,uv);
            //half4 difColor = saturate(max( 0, bluredColor.a - prepassColor.a));
            half4 color = bluredColor * _Intensity;
            color.a = saturate(max(0, bluredColor.a - prepassColor.a) );
            color *= color.a;

            //color = bluredColor.a - prepassColor.a;
            // color.a = 1;
            return  color;
        }

        ENDHLSL

        Pass
        {


            Blend [_SrcBlend] [_DstBlend]
            ZTest Always    // всегда рисуем, независимо от текущей глубины в буфере
            ZWrite Off      // и ничего в него не пишем
            Cull Off        // рисуем все стороны меша

            HLSLPROGRAM

            #pragma vertex Vertex
            #pragma fragment Fragment

            ENDHLSL
        }
    }
}