半透明的shader

需求：相機和人物之間有遮擋物，将遮擋物做半透明處理

Shader "Custom/Diffuse/Transparent" {
Properties {
    _MainTex ("Base (RGB)", 2D) = "white" {}
    _TransparentScale("Transparent",Range(0,1)) = 1
}
SubShader {
    Tags {"Queue" = "Transparent" "IgnoreProjector" = "True" "RenderType" = "Transparent"}
    LOD 200

CGPROGRAM
#pragma surface surf Lambert noforwardadd alpha:fade

sampler2D _MainTex;
    float _TransparentScale;

struct Input {
    float2 uv_MainTex;
};

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

Fallback "Mobile/VertexLit"
}