//==========================================================
//
// Copyright (c) Guangzhou Shixiang Technology Co.,Ltd.
// All rights reserved.
//
//==========================================================

// Upgrade NOTE: replaced 'mul(UNITY_MATRIX_MVP,*)' with 'UnityObjectToClipPos(*)'
Shader "GxrSdk/QuitDialog/Image"
{
	Properties
	{
		[PerRendererData] _MainTex("Sprite Texture", 2D) = "white" {}
		_Color("Tint", Color) = (1,1,1,1)
		[MaterialToggle] PixelSnap("Pixel snap", Float) = 0
		_MaskLayer("Culling Mask",2D) = "white"{}//混合的图片，设置为白色的图片，任何颜色与白色混合，其颜色不变
		_radius("radius",float) = 2
	}

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

			Cull Off         //关闭背面剔除 
			Lighting Off     //关闭灯光 Opaque
			//ZWrite Off       //关闭Z缓冲
			ZTest Always
			Blend SrcAlpha OneMinusSrcAlpha //混合源系数one(1)  目标系数OneMinusSrcAlpha(1-one=0)
			Pass
			{
				CGPROGRAM
				#pragma vertex vert
				#pragma fragment frag
				#pragma multi_compile _ PIXELSNAP_ON       //告诉Unity编译不同版本的Shader,这里和后面vert中的PIXELSNAP_ON对应
				#pragma shader_feature ETC1_EXTERNAL_ALPHA
				#include "UnityCG.cginc"

				struct appdata_t                           //vert输入
				{
					float4 vertex   : POSITION;
					float4 color    : COLOR;
					float2 texcoord : TEXCOORD0;
				};

				struct v2f                                 //vert输出数据结构
				{
					float4 vertex   : SV_POSITION;
					fixed4 color : COLOR;
					float2 texcoord  : TEXCOORD0;
				};

				fixed4 _Color;

				v2f vert(appdata_t IN)
				{
					v2f OUT;
					OUT.vertex = UnityObjectToClipPos(IN.vertex);
					OUT.texcoord = IN.texcoord;
					OUT.color = IN.color * _Color;
					#ifdef PIXELSNAP_ON
					OUT.vertex = UnityPixelSnap(OUT.vertex);
					#endif

					return OUT;
				}

				sampler2D _MainTex;
				sampler2D _AlphaTex;
				sampler2D _MaskLayer;
				float _radius;

				fixed4 SampleSpriteTexture(float2 uv)
				{
					fixed4 color = tex2D(_MainTex, uv);

	//#if ETC1_EXTERNAL_ALPHA         //etc1没有透明通道，从另一图中取a值
	//				// get the color from an external texture (usecase: Alpha support for ETC1 on android)
	//				//color.a = tex2D(_AlphaTex, uv).r;
	//#endif //ETC1_EXTERNAL_ALPHA

					return color;
				}

				fixed4 frag(v2f IN) : SV_Target
				{
					fixed4 c = SampleSpriteTexture(IN.texcoord) * IN.color;

					//c.rgb *= 1;
					return c;
				}
			ENDCG
			}
		}
}