[游戏开发]Unity 模型被建筑物遮挡处理（二）（显示模型轮廓）

当模型被建筑物遮挡的时候，如果要显示模型的轮廓时，修改模型的Shader：

Shader "Unlit/MaskShader"
{
	Properties
	{
		[NoScaleoffset]_MainTex ("Texture", 2D) = "white" {}
		_maskColor("MaskColor",Color) = (0,1,0)//轮廓颜色
	}
	
	SubShader
	{
		Tags { "RenderType"="Opaque" "Queue" = "Geometry+100"  }
		
		Pass
		{
			Blend SrcAlpha One
			ZTest Greater
            ZWrite Off

			CGPROGRAM
			#pragma vertex vert
			#pragma fragment frag
			
			#pragma multi_compile_fog
			#include "UnityCG.cginc"

			struct MeshData
			{
				float4 vertex : POSITION;
				float2 uv : TEXCOORD0;
				float3 normal : NORMAL;
			};

			struct Interpolator
			{
				float2 uv : TEXCOORD0;
				float4 vertex : SV_POSITION;
				float4 pos : TEXCOORD1;
				float3 normal : NORMAL;
			};

			sampler2D _MainTex;
			float4 _MainTex_ST;
			float4 _maskColor;
			
			Interpolator vert (MeshData v)
			{
				Interpolator o;
				o.vertex = UnityObjectToClipPos(v.vertex);
				o.uv = TRANSFORM_TEX(v.uv, _MainTex);
				o.pos = v.vertex;
				o.normal = v.normal;
				return o;
			}
			
			fixed4 frag (Interpolator i) : SV_Target
			{
				fixed4 col = fixed4(0,0,0,0.1);
				float3 wpos = mul(unity_ObjectToWorld, i.pos).xyz;
				float3 viewDir = UnityWorldSpaceViewDir(wpos);
				viewDir = normalize(viewDir);

				float3 normal = UnityObjectToWorldNormal(i.normal);
				float flag = 1 - saturate(dot(viewDir,normal));
				float br = pow(flag, 2.0);
				col = lerp(col , _maskColor , br);
				return col;
			}
			ENDCG
		}
		
		Pass
		{
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
			
            sampler2D _MainTex;
            float4 _MainTex_ST;
			float _Alpha;

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

            struct Interpolator
            {
                float2 uv : TEXCOORD0;
                float4 vertex : SV_POSITION;
            };

            Interpolator vert (MeshData v)
            {
                Interpolator o;
                o.vertex = UnityObjectToClipPos(v.vertex);
                o.uv = v.uv;
                return o;
            }

            float4 frag (Interpolator i) : SV_Target
            {
                fixed4 col = tex2D(_MainTex, i.uv);
                return col;
            }
            ENDCG
		}
	}
}