Shader "Unlit/ButtonBGMask/Circle"
{
    Properties
    {
        _MainTex("Texture", 2D) = "white" {}
        _Color("Main Color", Color) = (1,1,1,1)
        _Radius("Radius", Range(0, 1)) = 0.15
        _Thickness("Thickness", Range(0, 1)) = 0.02
        _Angle("Angle", Range(0, 1)) = 0
    }
        SubShader
        {
            Tags { "Queue" = "Transparent" "IngnoreProjector" = "True" "RenderType" = "Transparent" }
            LOD 200

            Pass
            {
                ZWrite Off
                Cull Off
                Blend SrcAlpha OneMinusSrcAlpha

                CGPROGRAM
                #pragma vertex vert
                #pragma fragment frag
                // make fog work
                #pragma multi_compile_fog

                #include "UnityCG.cginc"

                struct appdata
                {
                    float4 vertex : POSITION;
                    float2 uv : TEXCOORD0;
                };

                struct v2f
                {
                    float2 uv : TEXCOORD0;
                    UNITY_FOG_COORDS(1)
                    float4 vertex : SV_POSITION;
                };

                sampler2D _MainTex;
                fixed4 _Color;
                float4 _MainTex_ST;
                float _Radius, _Thickness, _Angle;

                v2f vert(appdata v)
                {
                    v2f o;
                    o.vertex = UnityObjectToClipPos(v.vertex);
                    o.uv = TRANSFORM_TEX(v.uv, _MainTex);
                    //UNITY_TRANSFER_FOG(o,o.vertex);
                    return o;
                }

                fixed4 frag(v2f i) : SV_Target
                {
                    // sample the texture
                    float alpha = 1.0f;
                    fixed4 col = tex2D(_MainTex, i.uv) * _Color;
                    float dis = (i.uv.x - 0.5) * (i.uv.x - 0.5) + (i.uv.y - 0.5) * (i.uv.y - 0.5);
                    if (dis<_Radius)
                    {
                        //col.a = 1.0;
                        //clip(-1);
                    }
                    else if (dis > _Radius + _Thickness)
                    {
                        col.a = 0.0;
                        clip(-1);
                    }
                    /*else {
                        float angletemp = atan2(i.uv.y - 0.5, i.uv.x - 0.5);
                        if (angletemp < (_Angle - 0.5) * 3.1415926 * 2)
                        {
                            col.a = 0.0;
                            clip(-1);
                        }
                        else {
                            col.a = (_Thickness * 0.5 - abs(dis - _Radius - _Thickness * 0.5)) / 0.008;
                        }
                    }*/
                    // apply fog
                    //UNITY_APPLY_FOG(i.fogCoord, col);
                    return col;
                }
                ENDCG
            }
        }
}