u3d无锯齿遮罩shader-可用于ugui

1、环境

unity: 5.6~2017

2、效果图

要比ugui中的mask组件的效果好很多

3、源码

// lizhihai
// 遮罩shader

Shader "Custom/CircleMask" {
    Properties {
        _MainTex ("MainTex", 2D) = "white" {}
        _MaskTex ("MaskTex", 2D) = "white" {}
        [HideInInspector]_Cutoff ("Alpha cutoff", Range(0,1)) = 0.5

        //MASK SUPPORT ADD
        _StencilComp ("Stencil Comparison", Float) = 8
        _Stencil ("Stencil ID", Float) = 0
        _StencilOp ("Stencil Operation", Float) = 0
        _StencilWriteMask ("Stencil Write Mask", Float) = 255
        _StencilReadMask ("Stencil Read Mask", Float) = 255
        _ColorMask ("Color Mask", Float) = 15
        //MASK SUPPORT END
    }
    SubShader {
        Tags {
            "IgnoreProjector"="True"
            "Queue"="Transparent"
            "RenderType"="Transparent"
        }
        //MASK SUPPORT ADD
        Stencil
        {
            Ref [_Stencil]
            Comp [_StencilComp]
            Pass [_StencilOp]
            ReadMask [_StencilReadMask]
            WriteMask [_StencilWriteMask]
        }
        ColorMask [_ColorMask]
        //MASK SUPPORT END
        Pass {
            Name "FORWARD"
            Tags {
                "LightMode"="ForwardBase"
            }
            Blend SrcAlpha OneMinusSrcAlpha
            ZWrite Off

            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            #define UNITY_PASS_FORWARDBASE
            #include "UnityCG.cginc"
            #pragma multi_compile_fwdbase
            #pragma only_renderers d3d9 d3d11 glcore gles
            #pragma target 3.0
            uniform sampler2D _MainTex; uniform float4 _MainTex_ST;
            uniform sampler2D _MaskTex; uniform float4 _MaskTex_ST;
            struct VertexInput {
                float4 vertex : POSITION;
                float2 texcoord0 : TEXCOORD0;
            };
            struct VertexOutput {
                float4 pos : SV_POSITION;
                float2 uv0 : TEXCOORD0;
            };
            VertexOutput vert (VertexInput v) {
                VertexOutput o = (VertexOutput)0;
                o.uv0 = v.texcoord0;
                o.pos = UnityObjectToClipPos( v.vertex );
                return o;
            }
            float4 frag(VertexOutput i) : COLOR {
////// Lighting:
                float4 _MainTex_var = tex2D(_MainTex,TRANSFORM_TEX(i.uv0, _MainTex));
                float3 finalColor = _MainTex_var.rgb;
                float4 _MaskTex_var = tex2D(_MaskTex,TRANSFORM_TEX(i.uv0, _MaskTex));
                return fixed4(finalColor,_MaskTex_var.a);
            }
            ENDCG
        }
    }
    FallBack "Diffuse"
}