// Unity built-in shader source. Copyright (c) 2016 Unity Technologies. MIT license (see license.txt)

Shader "XUi/GuideMask"
{
    Properties
    {
        [PerRendererData] _MainTex ("Sprite Texture", 2D) = "white" {}
        _Color ("Tint", Color) = (1,1,1,1)

        _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

        [Toggle(UNITY_UI_ALPHACLIP)] _UseUIAlphaClip ("Use Alpha Clip", Float) = 0
        
        //-------------------add----------------------
        _Center("Center", Vector) = (0, 0, 0, 0)
        _Silder ("_Silder", Range (0,1000)) = 1000 // sliders
        _SquareOrCircle("_SquareOrCircle", Range (0,1)) = 0
        _GuideAplha("_GuideAplha", Range(0,1)) = 0
        //-------------------add----------------------
    }

    SubShader
    {
        Tags
        {
            "Queue"="Transparent"
            "IgnoreProjector"="True"
            "RenderType"="Transparent"
            "PreviewType"="Plane"
            "CanUseSpriteAtlas"="True"
        }

        Stencil
        {
            Ref [_Stencil]
            Comp [_StencilComp]
            Pass [_StencilOp]
            ReadMask [_StencilReadMask]
            WriteMask [_StencilWriteMask]
        }

        Cull Off
        Lighting Off
        ZWrite Off
        ZTest [unity_GUIZTestMode]
        Blend SrcAlpha OneMinusSrcAlpha
        ColorMask [_ColorMask]

        Pass
        {
            Name "Default"
            HLSLPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            
            #include "UnityCG.cginc"
            //#include Core
            #include "UnityUI.cginc"

            #pragma multi_compile __ UNITY_UI_CLIP_RECT
            #pragma multi_compile __ UNITY_UI_ALPHACLIP
            #pragma multi_compile __ _XCLIP_RECT_INVERSE _XCLIP_RECT_HIDE

            struct appdata_t
            {
                float4 vertex   : POSITION;
                float4 color    : COLOR;
                float2 texcoord : TEXCOORD0;
                UNITY_VERTEX_INPUT_INSTANCE_ID
            };

            struct v2f
            {
                float4 vertex   : SV_POSITION;
                fixed4 color    : COLOR;
                float2 texcoord  : TEXCOORD0;
                float4 worldPosition : TEXCOORD1;
                UNITY_VERTEX_OUTPUT_STEREO
            };
            
            //-------------------add----------------------
            float4 _ClipRect;
            half4 _Color;
            half4 _TextureSampleAdd;
            half _GuideAplha;
            //-------------------add----------------------

            v2f vert(appdata_t v)
            {
                v2f OUT;
                UNITY_SETUP_INSTANCE_ID(v);
                UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(OUT);
                OUT.worldPosition = v.vertex;
                OUT.vertex = UnityObjectToClipPos(OUT.worldPosition);

                OUT.texcoord = v.texcoord;

                OUT.color = v.color * _Color;
                return OUT;
            }
            float4 _XClipRect[4];
            sampler2D _MainTex;
            void RectClip(inout float4 color, float2 clipPos)
            {
                #if _XCLIP_RECT || _XCLIP_RECT_INVERSE
                    clipPos = clipPos / _ScreenParams.xy;
                    clipPos.y = lerp(clipPos.y, 1 - clipPos.y, step(_ProjectionParams.x, 0));

                    #if defined(SHADER_API_D3D11) || defined(SHADER_API_D3D9)
                        clipPos.y = 1 - clipPos.y;
                    #endif

                    float rectMask = step(0, dot(normalize(clipPos - _XClipRect[0].xy), _XClipRect[2].xy))
                                * step(0, dot(normalize(clipPos - _XClipRect[0].zw), _XClipRect[2].zw))
                                * step(0, dot(normalize(clipPos - _XClipRect[1].xy), _XClipRect[3].xy))
                                * step(0, dot(normalize(clipPos - _XClipRect[1].zw), _XClipRect[3].zw));

                    #ifdef _XCLIP_RECT
                        color.a *= rectMask;
                    #else
                        color.a *= 1 - rectMask;
                    #endif
                #endif
            }
            half4 frag(v2f IN) : SV_Target
            {
                half4 color = (tex2D(_MainTex, IN.texcoord) + _TextureSampleAdd) * IN.color;

                #ifdef UNITY_UI_CLIP_RECT
                color.a *= UnityGet2DClipping(IN.worldPosition.xy, _ClipRect);
                #endif

                #ifdef UNITY_UI_ALPHACLIP
                clip (color.a - 0.001);
                #endif

                //-------------------add----------------------
                #if _XCLIP_RECT_INVERSE
                    RectClip(color, IN.vertex.xy);
                    color.a *= _GuideAplha;
                #elif _XCLIP_RECT_HIDE
                    color.a = 0;
                #endif
                //-------------------add----------------------
                
                return color;
            }
         ENDHLSL
        }
    }
}
add _ReduceTime、_TotalTime 、 _StartTime three params for playing shrink tween