Shader "Zhanyou/SkillWarningSector" {
	Properties
	{
	    _TintColor ("Tint Color", Color) = (0.5,0.5,0.5,0.5)
	    _MainTex ("Particle Texture", 2D) = "white" {}
        // 扇形边线参数，四座标代表Cos，1f / Tan，直线sqrt(A ^ 2 + B ^ 2)
		_Edge("Edge", Vector) = (1, 0, 0, 0)
		_Scale("Scale", Float) = 1
	}
    Subshader {
		Tags{ "Queue" = "Transparent-1" }
        ZWrite Off
        Lighting Off
		ColorMask RGB
		Blend SrcAlpha OneMinusSrcAlpha
		
		CGINCLUDE
        #pragma vertex vert
        #pragma fragment frag
        #include "UnityCG.cginc"

		struct v2f {
			float2 uv : TEXCOORD0;
			float4 pos : SV_POSITION;
			float4 color : COLOR;
		};

		struct a2v {
			float4 vertex : POSITION;
			float2 texcoord : TEXCOORD0;
			float4 color : COLOR;
		};

	    v2f vert(a2v v)
	    {
		    v2f o;
		    UNITY_INITIALIZE_OUTPUT(v2f, o);
		    o.pos = UnityObjectToClipPos(v.vertex);
	    	o.uv = v.texcoord;
	    	o.color = v.color;
	    	return o;
	    }

        uniform sampler2D _MainTex;
        uniform float4 _TintColor;
		uniform half4 _Edge;
		uniform half _Scale;

	    fixed4 frag(v2f i) : SV_Target
	    {
		    float2 uv = i.uv - 0.5;
			if (dot(normalize(uv), float2(0, 1)) > _Edge.x)
			{
				uv.x = abs(uv.x);
				half dist = (uv.y - _Edge.y * uv.x) / _Edge.z;
				dist = max(0, 0.5 - dist);
				half radius = distance(i.uv, float2(0.5, 0.5));
				dist = max(dist, radius);
				dist = max(0, dist * _Scale + (1 - _Scale) * 0.5);
				dist = 0.5 + dist;
				uv.x = 0.5;
				uv.y = dist;
				fixed4 res = tex2D(_MainTex, uv);
				res *= _TintColor * i.color;
				res = min(res, fixed4(1, 1, 1, 1));
				return res;
			}
			else
				return fixed4(0, 0, 0, 0);
	    }
        ENDCG
		
		Pass
		{
            Stencil
            {
                Ref 1
                Comp Equal
            }
			CGPROGRAM
			ENDCG
		}
		
		Pass
		{
            Stencil
            {
                Ref 1
                Comp NotEqual
            }
            ZTest Always
            CGPROGRAM
            ENDCG
        }
    }
}