Shader "Custom/WireframeURP"
{
    Properties
    {
        _MainTex ("Texture", 2D) = "white" {}
        _LineColor("Line Color", Color) = (1, 1, 1, 1)
        _BGColor("Background Color", Color) = (0, 0, 0, 0)
        _LineWidth("Line Width", Range(0,0.1)) = 0.005
    }

    SubShader
    {
        Tags { "RenderType"="Opaque" }
        LOD 100

        Pass
        {
            Name "Wireframe"
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            #pragma target 3.0
            #include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/Core.hlsl"

            struct appdata
            {
                float4 vertex : POSITION;
                float3 barycentric : TEXCOORD0; // Barycentric coordinates for wireframe
            };

            struct v2f
            {
                float2 uv : TEXCOORD0;
                float3 barycentric : TEXCOORD1;
                float4 vertex : SV_POSITION;
            };

            sampler2D _MainTex;
            float4 _MainTex_ST;
            float4 _LineColor;
            float4 _BGColor;
            float _LineWidth;

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

            half4 frag (v2f i) : SV_Target
            {
                half3 bary = i.barycentric;
                bary = fwidth(bary) * _LineWidth + bary;
                half mask = step(1, abs(bary.x) + abs(bary.y) + abs(bary.z));
                half4 col = lerp(_LineColor, _BGColor, mask);
                return col;
            }
            ENDCG
        }
    }
}