Shader "Custom/OutlineText"
{
    Properties
    {
        _MainTex ("Font Texture", 2D) = "white" {}
        _OutlineColor("Outline Color", Color) = (0,0,0,1)
        _OutlineSize("Outline Size", Float) = 1.0
    }
 
    SubShader
    {
        Tags { "Queue"="Transparent" }
        Lighting Off
        Blend SrcAlpha OneMinusSrcAlpha
        Pass
        {
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            #include "UnityCG.cginc"
            
            struct appdata
            {
                float4 vertex : POSITION;
                float2 uv : TEXCOORD0;
            };
            
            struct v2f
            {
                float2 uv : TEXCOORD0;
                float4 vertex : SV_POSITION;
            };
            
            sampler2D _MainTex;
            float4 _MainTex_ST;
            float4 _OutlineColor;
            float _OutlineSize;
            
            v2f vert (appdata v)
            {
                v2f o;
                o.vertex = UnityObjectToClipPos(v.vertex);
                o.uv = TRANSFORM_TEX(v.uv, _MainTex);
                return o;
            }
            
            half4 frag (v2f i) : SV_Target
            {
                fixed4 col = tex2D(_MainTex, i.uv);
                fixed4 outline = tex2D(_MainTex, i.uv + float2(_OutlineSize, 0));
                outline += tex2D(_MainTex, i.uv + float2(0, _OutlineSize));
                outline += tex2D(_MainTex, i.uv + float2(-_OutlineSize, 0));
                outline += tex2D(_MainTex, i.uv + float2(0, -_OutlineSize));
                col = lerp(col, _OutlineColor, outline.a); // Adjust blending as needed
                return col;
            }
            ENDCG
        }
    }
}