Shader "Custom/TrailRenderer" {
    Properties {
        _MainTex ("Base (RGB)", 2D) = "white" {}
    }
    SubShader {
        Tags { "RenderType"="Transparent"  "IgnoreProjector"="True"  "Queue"="Transparent"}
        LOD 200
        Blend SrcAlpha OneMinusSrcAlpha
        CGPROGRAM
        #pragma surface surf NoLight vertex:vert alpha noforwardadd
 
        //光照方程，名字为Lighting接#pragma suface后的光照方程名称 
        //lightDir :顶点到光源的单位向量
        //viewDir  :顶点到摄像机的单位向量   
        //atten    :关照的衰减系数 
        float4 LightingNoLight(SurfaceOutput s, float3 lightDir,half3 viewDir, half atten) 
        { 
            float4 c ; 
            c.rgb =  s.Albedo;
            c.a = s.Alpha; 
            return c; 
        }
 
        sampler2D _MainTex;
        fixed4 _SelfCol;
 
        struct Input 
        {
            float2 uv_MainTex;
            float4 vertColor;
        };
 
        void vert(inout appdata_full v, out Input o)
        {
            o.vertColor = v.color;
            o.uv_MainTex = v.texcoord;
        }
 
        void surf (Input IN, inout SurfaceOutput o) 
        {
            half4 c = tex2D (_MainTex, IN.uv_MainTex);
            o.Alpha = c.a * IN.vertColor.a;
            o.Albedo = IN.vertColor.rgb;
        }
 
 
        ENDCG
    } 
    FallBack "Diffuse"
}