如何在Unity着色器中偏移正常的UV？

Shader "Custom/OffsetUV"
{
    Properties
    {
        _MainTex ("Texture", 2D) = "white" {}
        _Offset ("UV Offset", Vector) = (0, 0)
    }
    
    SubShader
    {
        Tags { "RenderType"="Opaque" }
        LOD 200
        
        CGPROGRAM
        #pragma surface surf Lambert
        
        sampler2D _MainTex;
        float2 _Offset;
        
        struct Input
        {
            float2 uv_MainTex;
        };
        
        void surf (Input IN, inout SurfaceOutput o)
        {
            // 偏移UV坐标
            float2 offsetUV = IN.uv_MainTex + _Offset;
            
            // 采样纹理
            fixed4 c = tex2D(_MainTex, offsetUV);
            
            // 输出颜色
            o.Albedo = c.rgb;
            o.Alpha = c.a;
        }
        ENDCG
    }
    FallBack "Diffuse"
}