unity shader 普通物体接受阴影

Shader "Unlit/shadow"
{
	Properties
	{
		_MainTex ("Texture", 2D) = "white" {}
	}
	SubShader
	{
		Tags { "RenderType"="Opaque" }
		LOD 100
		
		Pass
		{
			Tags{"LightMode" = "ForwardBase"}
			CGPROGRAM
			#pragma vertex vert
			#pragma fragment frag
			#pragma multi_compile_fog
#pragma multi_compile_fwdbase      // 非常重要，不然没法正确计算阴影
			#include "UnityCG.cginc"
			#include "Lighting.cginc"
			#include "AutoLight.cginc"
			struct appdata
			{
				float4 vertex : POSITION;
				float3 normal : NORMAL;
				float2 uv : TEXCOORD0;
			};

			struct v2f
			{
				float2 uv : TEXCOORD0;
				float4 vertex_world : TEXCOORD1;
				float3 normal : NORMAL;
				float4 pos : SV_POSITION;
				SHADOW_COORDS(2)            // 2 即 TEXCOORD2
			};

			sampler2D _MainTex;
			float4 _MainTex_ST;
			
			v2f vert (appdata v)
			{
				v2f o;
				o.vertex_world = v.vertex;
				o.pos = UnityObjectToClipPos(v.vertex);
				o.uv = TRANSFORM_TEX(v.uv, _MainTex);
				o.normal = v.normal;
				TRANSFER_SHADOW(o)            // 填充阴影坐标，根据平台自动调整
				return o;
			}
			
			fixed4 frag (v2f i) : SV_Target
			{
				fixed4 col = tex2D(_MainTex, i.uv);
				fixed shadow = SHADOW_ATTENUATION(i);     // 根据平台自己得到相应值
				float4 lightColor = _LightColor0;
				float3 lightDir = WorldSpaceLightDir(i.vertex_world).xyz;
				return col * lightColor * saturate(dot(i.normal, normalize(lightDir))) * shadow;  
				// shadow 和 最终颜色乘上就可
			}
			
			ENDCG
		}
	}
	FallBack "Specular"
}

效果：