Mask 3D Object In Scroll Rect

I was trying to use 3D object in scroll rect but 3d object was visible outside the scroll rect. So I found https://forum.unity.com/threads/ui-and-masking-3d-meshes-in-a-scrollrect.358475/ this post and follow the instructions. I managed to get it work but not completely. As you can see in the picture, mask is working but probaby something wrong with the shader. Can you guys take a look at the shader code? Lights and shadows are not working.

Object on the right side is the original one, left side is the masked one.

Code (CSharp):

1. // https://forum.unity3d.com/threads/ui-and-masking-3d-meshes-in-a-scrollrect.358475/
2. Shader "Custom/NewSurfaceShader" {
3.     Properties {
4.         _Color ("Color", Color) = (1,1,1,1)
5.         _MainTex ("Albedo (RGB)", 2D) = "white" {}
6.         _Glossiness ("Smoothness", Range(0,1)) = 0.5
7.         _Metallic ("Metallic", Range(0,1)) = 0.0
8.  
9.  
10.         _StencilComp("Stencil Comparison", Float) = 8
11.         _Stencil("Stencil ID", Float) = 0
12.         _StencilOp("Stencil Operation", Float) = 0
13.         _StencilWriteMask("Stencil Write Mask", Float) = 255
14.         _StencilReadMask("Stencil Read Mask", Float) = 255
15.  
16.         _ColorMask("Color Mask", Float) = 15
17.  
18.         [Toggle(UNITY_UI_ALPHACLIP)] _UseUIAlphaClip("Use Alpha Clip", Float) = 0
19.     }
20.  
21.     SubShader
22.     {
23.         Tags { "RenderType"="Opaque""Queue"="Transparent"}
24.         LOD 200
25.         ZWrite On
26.         ZTest[unity_GUIZTestMode]
27.         Blend SrcAlpha OneMinusSrcAlpha
28.         ColorMask[_ColorMask]
29.  
30.      
31.         Stencil
32.         {
33.             Ref 1
34.             Comp LEqual
35.             Pass Keep
36.             ReadMask [_StencilReadMask]
37.             WriteMask [_StencilWriteMask]
38.         }
39.  
40.         CGPROGRAM
41.         // Physically based Standard lighting model, and enable shadows on all light types
42.         #pragma surface surf Standard vertex:vert fullforwardshadows
43.         // Use shader model 3.0 target, to get nicer looking lighting
44.         #pragma target 3.0
45.  
46.         #include "UnityUI.cginc"
47.          
48.         struct Input
49.         {
50.             float2 uv_MainTex;
51.             float4 worldPosition;
52.         };
53.  
54.         void vert(inout appdata_full v, out Input o)
55.         {
56.             UNITY_INITIALIZE_OUTPUT(Input, o);
57.             o.worldPosition = v.vertex;
58.         }
59.      
60.  
61.         sampler2D _MainTex;
62.         half _Glossiness;
63.         half _Metallic;
64.         fixed4 _Color;
65.         // float4 _ClipRect;
66.  
67.         void surf (Input IN, inout SurfaceOutputStandard o) {
68.             // Albedo comes from a texture tinted by color
69.             fixed4 c = _Color;
70.             o.Albedo = c.rgb;
71.             // Metallic and smoothness come from slider variables
72.             o.Metallic = _Metallic;
73.             o.Smoothness = _Glossiness;
74.             o.Alpha = c.a;
75.          
76.             #ifdef UNITY_UI_ALPHACLIP
77.             clip(o.Alpha - 0.001);
78.             #endif
79.         }
80.         ENDCG
81.     }
82.     FallBack "Diffuse"
83. }