Built-in シェーダーで Texture2DArray を使ってみた

unrecognized identifier 'sampler2DArray' で悩んだのだけど
次の書き方で一応 Texture2DArray は機能したので、メモします

Shader "Unlit/NewUnlitShader"
{
    Properties
    {
        _MainTex ("Texture", 2D) = "white" {}
        _BaseColor("Base Color", 2DArray) = "" {}
    }
    SubShader
    {
        Tags { "RenderType"="Opaque" }
        LOD 100

        Pass
        {
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            // make fog work
            #pragma multi_compile_fog

            #include "UnityCG.cginc"

            struct appdata
            {
                float4 vertex : POSITION;
                float2 uv : TEXCOORD0;
            };

            struct v2f
            {
                float2 uv : TEXCOORD0;
                UNITY_FOG_COORDS(1)
                float4 vertex : SV_POSITION;
            };

            sampler2D _MainTex;
            Texture2DArray _BaseColor;
            SamplerState sampler_BaseColor;
            float4 _MainTex_ST;

            v2f vert (appdata v)
            {
                v2f o;
                o.vertex = UnityObjectToClipPos(v.vertex);
                o.uv = TRANSFORM_TEX(v.uv, _MainTex);
                UNITY_TRANSFER_FOG(o,o.vertex);
                return o;
            }

            fixed4 frag (v2f i) : SV_Target
            {
                fixed4 baseColorTex = _BaseColor.Sample(sampler_BaseColor, float3(i.uv, 0));
                return baseColorTex;
            }
            ENDCG
        }
    }
}