Shader "Custom/AlphaTest" {Properties {_Color ("Color Tint", Color) = (1, 1, 1, 1)_MainTex ("Main Tex", 2D) = "white" {}//声明控制透明度测试时使用的阈值，其范围为[0,1]_Cutoff ("Alpha Cutoff", Range(0, 1)) = 0.5}SubShader {Tags {"Queue"="AlphaTest" "IgnoreProjector"="True" "RenderType"="TransparentCutout"}//RenderType标签可以让这个Unity把这个Shader归入到提前定义的组中//通常，使用透明度测试的shader都应该在SubShader中设置这三个标签Pass {Tags { "LightMode"="ForwardBase" }CGPROGRAM#pragma vertex vert#pragma fragment frag#include "Lighting.cginc"fixed4 _Color;sampler2D _MainTex;float4 _MainTex_ST;fixed _Cutoff;//由于其范围是[0,1]，所以可以用fixed精度来存储struct a2v {float4 vertex : POSITION;float3 normal : NORMAL;float4 texcoord : TEXCOORD0;};struct v2f {float4 pos : SV_POSITION;float3 worldNormal : TEXCOORD0;float3 worldPos : TEXCOORD1;float2 uv : TEXCOORD2;};v2f vert(a2v v) {v2f o;o.pos = UnityObjectToClipPos(v.vertex);//在顶点着色器中计算出世界空间下的法线方向和顶点位置以及变换后的坐标o.worldNormal = UnityObjectToWorldNormal(v.normal);o.worldPos = mul(unity_ObjectToWorld, v.vertex).xyz;o.uv = TRANSFORM_TEX(v.texcoord, _MainTex);return o;}fixed4 frag(v2f i) : SV_Target {fixed3 worldNormal = normalize(i.worldNormal);fixed3 worldLightDir = normalize(UnityWorldSpaceLightDir(i.worldPos));fixed4 texColor = tex2D(_MainTex, i.uv);// Alpha test 若texColor.a小于_Cutoff,则物体完全透明clip (texColor.a - _Cutoff);fixed3 albedo = texColor.rgb * _Color.rgb;fixed3 ambient = UNITY_LIGHTMODEL_AMBIENT.xyz * albedo;fixed3 diffuse = _LightColor0.rgb * albedo * max(0, dot(worldNormal, worldLightDir));return fixed4(ambient + diffuse, 1.0);}ENDCG}} //使用内置VertexLit来回调shader，不仅可以保证在我们编写的SubShader无法在当前显卡上工作时可以有合适的替代shader,还可以保证使用透明度测试的物体可以正确的向其他物体投射阴影FallBack "Transparent/Cutout/VertexLit"
}

Pass {Tags { "LightMode"="ForwardBase"}//Turn off cullingCull off