第一个SubShader:固定管线
第二个SubShader:unity shader
第三个SubShader:顶点片段

Shader "Custom/Transparent" {
    Properties {
        _Color ("Main Color", Color) = (1,1,1,0.6)
        _MainTex ("Base (RGB)", 2D) = "white" {}
    }
    SubShader {
        Tags { "Queue"="Transparent" }
        Pass{
            Blend SrcAlpha OneMinusSrcAlpha
            Color[_Color]
            SetTexture[_MainTex]{
                combine previous * texture
            }

        }
    }
    SubShader {
        Tags { "Queue"="Transparent" }
        CGPROGRAM
        #pragma surface surf Lambert alpha

        fixed4 _Color;
        sampler2D _MainTex;

        struct Input {
            float2 uv_MainTex;
        };
        void surf (Input IN, inout SurfaceOutput o) {
            fixed4 c = tex2D(_MainTex, IN.uv_MainTex) * _Color;
            o.Albedo = c.rgb;
            o.Alpha = c.a;
        }

        ENDCG
    }
    SubShader {
        Tags { "Queue"="Transparent" }
        Blend SrcAlpha OneMinusSrcAlpha
        Pass{
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            #include "UnityCG.cginc"

            fixed4 _Color;
            sampler2D _MainTex;

            struct v2f{
                float4 vertex : POSITION;
                float2 texcoord : TEXCOORD0;
            };

            v2f vert(appdata_base v){
                v2f o;
                  o.vertex = mul(UNITY_MATRIX_MVP,v.vertex);
                  o.texcoord = v.texcoord;
                  return o;
            }

            fixed4 frag(v2f i):COLOR{
                return tex2D(_MainTex, i.texcoord) * _Color;
            }

            ENDCG
        }
    }
    FallBack "Transparent/Diffuse"
}