Unity 毛玻璃效果（UGUI）

最近想在UI中加入类似Win7的毛玻璃效果，将弹窗UI的背景虚化。实现的原理很简单，就是对UI的背景做一下Blur。在实现过程中，我尝试了两种方法：

1、直接Blur UI后面的图像。

这是网上很多文章提供的方法，也比较容易想到。可以直接用Shader控制UI 背景Panel上Image组件的渲染。

因为Unity 提供了GrabPass，可以在Shader中很方便的拿到Panel下面的图像，即_GrabTexture。

问题在于如何对_GrabTexture做Blur处理。如果使用普通的高斯模糊，效果并不理想，原因在于模糊半径太小了，导致模糊后的图像太清晰，玻璃“不够毛”。

我前面一篇分析Bloom效果的日志，提供了一种方法，先对图像做向下采样，然后再做模糊处理，这样做出来的模糊效果比较理想，但是无法通过一个Pass实现。而在Image控件上使用的Shader并不能自由的控制Pass，所以只能硬着头皮用一个Pass做大面积的模糊处理。所以我放弃了高斯模糊，而使用发现贴图扰动的方式做模糊处理。代码看起来很Low：

Shader "Custom/UIFrostedGlass"
{
	Properties
	{
		[PerRendererData] _MainTex ("Sprite Texture", 2D) = "white" {}
		_NormalTex ("Sprite Texture", 2D) = "white" {}
		_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
	}

	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
		GrabPass{ }
		Pass
		{
		CGPROGRAM
			#pragma vertex vert
			#pragma fragment frag

			#include "UnityCG.cginc"
			#include "UnityUI.cginc"
			
			struct appdata_t
			{
				float4 vertex   : POSITION;
				float4 color    : COLOR;
				float2 texcoord : TEXCOORD0;
			};
			struct v2f
			{
				float4 vertex   : SV_POSITION;
				half2 texcoord  : TEXCOORD0;
				float4 worldPosition : TEXCOORD1;
			};

			v2f vert(appdata_t IN)
			{
				v2f OUT;
				OUT.worldPosition = IN.vertex;
				OUT.vertex = mul(UNITY_MATRIX_MVP, OUT.worldPosition);
				OUT.texcoord = half2(IN.texcoord.x, 1-IN.texcoord.y);				
				return OUT;
			}

			sampler2D _MainTex;
			uniform half4 _MainTex_TexelSize;
			sampler2D _GrabTexture;
			uniform half4 _GrabTexture_TexelSize;
			sampler2D _NormalTex;
			float _RandomParam;
			static const half4 curve4[7] = { 	half4(0.0205,0.0205,0.0205,0), 
												half4(0.0855,0.0855,0.0855,0), 
												half4(0.232,0.232,0.232,0),
												half4(0.324,0.324,0.324,1), 
												half4(0.232,0.232,0.232,0), 
												half4(0.0855,0.0855,0.0855,0), 
												half4(0.0205,0.0205,0.0205,0) };
			fixed4 frag(v2f IN) : SV_Target
			{
				half4 nor = tex2D(_NormalTex, IN.texcoord *8);
				half4 nor2 = tex2D(_NormalTex, IN.texcoord *12);
				half4 nor3 = tex2D(_NormalTex, IN.texcoord *23);
				half4 nor4 = tex2D(_NormalTex, IN.texcoord *26);
				half4 nor5 = tex2D(_NormalTex, IN.texcoord *33);
				half4 nor6 = tex2D(_NormalTex, IN.texcoord *41);
				half4 nor7 = tex2D(_NormalTex, IN.texcoord *51);
				half4 nor8 = tex2D(_NormalTex, IN.texcoord *62);
				half4 nor9 = tex2D(_NormalTex, IN.texcoord *73);
				half4 nor10 = tex2D(_NormalTex, IN.texcoord *86);
				half4 nor11 = tex2D(_NormalTex, IN.texcoord *93);
				half4 nor12 = tex2D(_NormalTex, IN.texcoord *91);


				half4 norcolor1 = tex2D(_GrabTexture, IN.texcoord + (20 * _GrabTexture_TexelSize * nor.xy));
				half4 norcolor2 = tex2D(_GrabTexture, IN.texcoord - (20 * _GrabTexture_TexelSize * nor.yz));
				half4 norcolor3 = tex2D(_GrabTexture, IN.texcoord + (20 * _GrabTexture_TexelSize * nor.zx));
				half4 norcolor21 = tex2D(_GrabTexture, IN.texcoord - (20 * _GrabTexture_TexelSize * nor2.xy));
				half4 norcolor22 = tex2D(_GrabTexture, IN.texcoord + (20 * _GrabTexture_TexelSize * nor2.yz));
				half4 norcolor23 = tex2D(_GrabTexture, IN.texcoord - (20 * _GrabTexture_TexelSize * nor2.zx));
				half4 norcolor31 = tex2D(_GrabTexture, IN.texcoord + (20 * _GrabTexture_TexelSize * nor3.xy));
				half4 norcolor32 = tex2D(_GrabTexture, IN.texcoord - (20 * _GrabTexture_TexelSize * nor3.yz));
				half4 norcolor33 = tex2D(_GrabTexture, IN.texcoord + (20 * _GrabTexture_TexelSize * nor3.zx));
				half4 norcolor41 = tex2D(_GrabTexture, IN.texcoord - (20 * _GrabTexture_TexelSize * nor4.xy));
				half4 norcolor42 = tex2D(_GrabTexture, IN.texcoord + (30 * _GrabTexture_TexelSize * nor4.yz));
				half4 norcolor43 = tex2D(_GrabTexture, IN.texcoord - (30 * _GrabTexture_TexelSize * nor4.zx));
				half4 norcolor51 = tex2D(_GrabTexture, IN.texcoord + (30 * _GrabTexture_TexelSize * nor5.xy));
				half4 norcolor52 = tex2D(_GrabTexture, IN.texcoord - (30 * _GrabTexture_TexelSize * nor5.yz));
				half4 norcolor53 = tex2D(_GrabTexture, IN.texcoord + (30 * _GrabTexture_TexelSize * nor5.zx));
				half4 norcolor61 = tex2D(_GrabTexture, IN.texcoord - (30 * _GrabTexture_TexelSize * nor6.xy));
				half4 norcolor62 = tex2D(_GrabTexture, IN.texcoord + (40 * _GrabTexture_TexelSize * nor6.yz));
				half4 norcolor63 = tex2D(_GrabTexture, IN.texcoord - (40 * _GrabTexture_TexelSize * nor6.zx));
				half4 norcolor71 = tex2D(_GrabTexture, IN.texcoord + (40 * _GrabTexture_TexelSize * nor7.xy));
				half4 norcolor72 = tex2D(_GrabTexture, IN.texcoord - (40 * _GrabTexture_TexelSize * nor7.yz));
				half4 norcolor73 = tex2D(_GrabTexture, IN.texcoord + (40 * _GrabTexture_TexelSize * nor7.zx));
				half4 norcolor81 = tex2D(_GrabTexture, IN.texcoord - (50 * _GrabTexture_TexelSize * nor8.xy));
				half4 norcolor82 = tex2D(_GrabTexture, IN.texcoord + (50 * _GrabTexture_TexelSize * nor8.yz));
				half4 norcolor83 = tex2D(_GrabTexture, IN.texcoord - (50 * _GrabTexture_TexelSize * nor8.zx));
				half4 norcolor91 = tex2D(_GrabTexture, IN.texcoord + (50 * _GrabTexture_TexelSize * nor9.xy));
				half4 norcolor92 = tex2D(_GrabTexture, IN.texcoord - (60 * _GrabTexture_TexelSize * nor9.yz));
				half4 norcolor93 = tex2D(_GrabTexture, IN.texcoord + (60 * _GrabTexture_TexelSize * nor9.zx));
				half4 norcolor101 = tex2D(_GrabTexture, IN.texcoord - (60 * _GrabTexture_TexelSize * nor10.xy));
				half4 norcolor102 = tex2D(_GrabTexture, IN.texcoord + (70 * _GrabTexture_TexelSize * nor10.yz));
				half4 norcolor103 = tex2D(_GrabTexture, IN.texcoord - (70 * _GrabTexture_TexelSize * nor10.zx));
				half4 norcolor111 = tex2D(_GrabTexture, IN.texcoord + (80 * _GrabTexture_TexelSize * nor11.xy));
				half4 norcolor112 = tex2D(_GrabTexture, IN.texcoord - (80 * _GrabTexture_TexelSize * nor11.yz));
				half4 norcolor113 = tex2D(_GrabTexture, IN.texcoord + (90 * _GrabTexture_TexelSize * nor11.zx));
				half4 norcolor121 = tex2D(_GrabTexture, IN.texcoord - (90 * _GrabTexture_TexelSize * nor12.xy));
				half4 norcolor122 = tex2D(_GrabTexture, IN.texcoord + (100 * _GrabTexture_TexelSize * nor12.yz));
				half4 norcolor123 = tex2D(_GrabTexture, IN.texcoord - (110 * _GrabTexture_TexelSize * nor12.zx));
				half4 color = (norcolor1 + norcolor2 + norcolor3 
				+ norcolor21 + norcolor22 + norcolor23
				+ norcolor31 + norcolor32 + norcolor33
				+ norcolor41 + norcolor42 + norcolor43 
				+ norcolor51 + norcolor52 + norcolor53
				+ norcolor61 + norcolor62 + norcolor63
				+ norcolor71 + norcolor72 + norcolor73 
				+ norcolor81 + norcolor82 + norcolor83
				+ norcolor91 + norcolor92 + norcolor93
				+ norcolor101 + norcolor102 + norcolor103 
				+ norcolor111 + norcolor112 + norcolor113
				+ norcolor121 + norcolor122 + norcolor123)/36;
				return color;
			}
		ENDCG
		}
	}
}

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Shader "Custom/UIFrostedGlass"

{

Properties

{

[PerRendererData] _MainTex ("Sprite Texture", 2D) = "white" {}

_NormalTex ("Sprite Texture", 2D) = "white" {}

_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

}

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

GrabPass{ }

Pass

{

CGPROGRAM

#pragma vertex vert

#pragma fragment frag

#include "UnityCG.cginc"

#include "UnityUI.cginc"

struct appdata_t

{

float4 vertex : POSITION;

float4 color : COLOR;

float2 texcoord : TEXCOORD0;

};

struct v2f

{

float4 vertex : SV_POSITION;

half2 texcoord : TEXCOORD0;

float4 worldPosition : TEXCOORD1;

};

v2f vert(appdata_t IN)

{

v2f OUT;

OUT.worldPosition = IN.vertex;

OUT.vertex = mul(UNITY_MATRIX_MVP, OUT.worldPosition);

OUT.texcoord = half2(IN.texcoord.x, 1-IN.texcoord.y);

return OUT;

}

sampler2D _MainTex;

uniform half4 _MainTex_TexelSize;

sampler2D _GrabTexture;

uniform half4 _GrabTexture_TexelSize;

sampler2D _NormalTex;

float _RandomParam;

static const half4 curve4[7] = { half4(0.0205,0.0205,0.0205,0),

half4(0.0855,0.0855,0.0855,0),

half4(0.232,0.232,0.232,0),

half4(0.324,0.324,0.324,1),

half4(0.232,0.232,0.232,0),

half4(0.0855,0.0855,0.0855,0),

half4(0.0205,0.0205,0.0205,0) };

fixed4 frag(v2f IN) : SV_Target

{

half4 nor = tex2D(_NormalTex, IN.texcoord *8);

half4 nor2 = tex2D(_NormalTex, IN.texcoord *12);

half4 nor3 = tex2D(_NormalTex, IN.texcoord *23);

half4 nor4 = tex2D(_NormalTex, IN.texcoord *26);

half4 nor5 = tex2D(_NormalTex, IN.texcoord *33);

half4 nor6 = tex2D(_NormalTex, IN.texcoord *41);

half4 nor7 = tex2D(_NormalTex, IN.texcoord *51);

half4 nor8 = tex2D(_NormalTex, IN.texcoord *62);

half4 nor9 = tex2D(_NormalTex, IN.texcoord *73);

half4 nor10 = tex2D(_NormalTex, IN.texcoord *86);

half4 nor11 = tex2D(_NormalTex, IN.texcoord *93);

half4 nor12 = tex2D(_NormalTex, IN.texcoord *91);

half4 norcolor1 = tex2D(_GrabTexture, IN.texcoord + (20 * _GrabTexture_TexelSize * nor.xy));

half4 norcolor2 = tex2D(_GrabTexture, IN.texcoord - (20 * _GrabTexture_TexelSize * nor.yz));

half4 norcolor3 = tex2D(_GrabTexture, IN.texcoord + (20 * _GrabTexture_TexelSize * nor.zx));

half4 norcolor21 = tex2D(_GrabTexture, IN.texcoord - (20 * _GrabTexture_TexelSize * nor2.xy));

half4 norcolor22 = tex2D(_GrabTexture, IN.texcoord + (20 * _GrabTexture_TexelSize * nor2.yz));

half4 norcolor23 = tex2D(_GrabTexture, IN.texcoord - (20 * _GrabTexture_TexelSize * nor2.zx));

half4 norcolor31 = tex2D(_GrabTexture, IN.texcoord + (20 * _GrabTexture_TexelSize * nor3.xy));

half4 norcolor32 = tex2D(_GrabTexture, IN.texcoord - (20 * _GrabTexture_TexelSize * nor3.yz));

half4 norcolor33 = tex2D(_GrabTexture, IN.texcoord + (20 * _GrabTexture_TexelSize * nor3.zx));

half4 norcolor41 = tex2D(_GrabTexture, IN.texcoord - (20 * _GrabTexture_TexelSize * nor4.xy));

half4 norcolor42 = tex2D(_GrabTexture, IN.texcoord + (30 * _GrabTexture_TexelSize * nor4.yz));

half4 norcolor43 = tex2D(_GrabTexture, IN.texcoord - (30 * _GrabTexture_TexelSize * nor4.zx));

half4 norcolor51 = tex2D(_GrabTexture, IN.texcoord + (30 * _GrabTexture_TexelSize * nor5.xy));

half4 norcolor52 = tex2D(_GrabTexture, IN.texcoord - (30 * _GrabTexture_TexelSize * nor5.yz));

half4 norcolor53 = tex2D(_GrabTexture, IN.texcoord + (30 * _GrabTexture_TexelSize * nor5.zx));

half4 norcolor61 = tex2D(_GrabTexture, IN.texcoord - (30 * _GrabTexture_TexelSize * nor6.xy));

half4 norcolor62 = tex2D(_GrabTexture, IN.texcoord + (40 * _GrabTexture_TexelSize * nor6.yz));

half4 norcolor63 = tex2D(_GrabTexture, IN.texcoord - (40 * _GrabTexture_TexelSize * nor6.zx));

half4 norcolor71 = tex2D(_GrabTexture, IN.texcoord + (40 * _GrabTexture_TexelSize * nor7.xy));

half4 norcolor72 = tex2D(_GrabTexture, IN.texcoord - (40 * _GrabTexture_TexelSize * nor7.yz));

half4 norcolor73 = tex2D(_GrabTexture, IN.texcoord + (40 * _GrabTexture_TexelSize * nor7.zx));

half4 norcolor81 = tex2D(_GrabTexture, IN.texcoord - (50 * _GrabTexture_TexelSize * nor8.xy));

half4 norcolor82 = tex2D(_GrabTexture, IN.texcoord + (50 * _GrabTexture_TexelSize * nor8.yz));

half4 norcolor83 = tex2D(_GrabTexture, IN.texcoord - (50 * _GrabTexture_TexelSize * nor8.zx));

half4 norcolor91 = tex2D(_GrabTexture, IN.texcoord + (50 * _GrabTexture_TexelSize * nor9.xy));

half4 norcolor92 = tex2D(_GrabTexture, IN.texcoord - (60 * _GrabTexture_TexelSize * nor9.yz));

half4 norcolor93 = tex2D(_GrabTexture, IN.texcoord + (60 * _GrabTexture_TexelSize * nor9.zx));

half4 norcolor101 = tex2D(_GrabTexture, IN.texcoord - (60 * _GrabTexture_TexelSize * nor10.xy));

half4 norcolor102 = tex2D(_GrabTexture, IN.texcoord + (70 * _GrabTexture_TexelSize * nor10.yz));

half4 norcolor103 = tex2D(_GrabTexture, IN.texcoord - (70 * _GrabTexture_TexelSize * nor10.zx));

half4 norcolor111 = tex2D(_GrabTexture, IN.texcoord + (80 * _GrabTexture_TexelSize * nor11.xy));

half4 norcolor112 = tex2D(_GrabTexture, IN.texcoord - (80 * _GrabTexture_TexelSize * nor11.yz));

half4 norcolor113 = tex2D(_GrabTexture, IN.texcoord + (90 * _GrabTexture_TexelSize * nor11.zx));

half4 norcolor121 = tex2D(_GrabTexture, IN.texcoord - (90 * _GrabTexture_TexelSize * nor12.xy));

half4 norcolor122 = tex2D(_GrabTexture, IN.texcoord + (100 * _GrabTexture_TexelSize * nor12.yz));

half4 norcolor123 = tex2D(_GrabTexture, IN.texcoord - (110 * _GrabTexture_TexelSize * nor12.zx));

half4 color = (norcolor1 + norcolor2 + norcolor3

+ norcolor21 + norcolor22 + norcolor23

+ norcolor31 + norcolor32 + norcolor33

+ norcolor41 + norcolor42 + norcolor43

+ norcolor51 + norcolor52 + norcolor53

+ norcolor61 + norcolor62 + norcolor63

+ norcolor71 + norcolor72 + norcolor73

+ norcolor81 + norcolor82 + norcolor83

+ norcolor91 + norcolor92 + norcolor93

+ norcolor101 + norcolor102 + norcolor103

+ norcolor111 + norcolor112 + norcolor113

+ norcolor121 + norcolor122 + norcolor123)/36;

return color;

}

ENDCG

}

采用了36次采样，初步得到了一个比较理想的效果：

frosted_glass_1

但这种方法也有问题，就是如果Blur图像中存在UI、文字等棱角分明的部分，Blur效果就很差：

frosted_glass_2

所以最终还是放弃了这个比较简单的方案。

2、多Pass Blur

由于Unity的渲染机制，Pass与DrawCall无关，也就是说，多Pass的后渲染处理，只能放在摄像机上在屏幕空间上做，而不能单独控制单个GameObject的渲染。所以，只能借助摄像机进行。结合上一篇Bloom中的方法，要先把场景渲染结果做向下采样处理，处理成一张小图，然后再做Blur处理。

这里用了一个省力的做法，给摄像机提供一个很小的RenderTexture，自动完成向下采样。RT越小，Blur效果越理想，经过测试，我用了1/32屏幕长宽的RT，得到RT后，创建一个Sprite赋值给Image组件，然后再用Shader在Image渲染的时候做Blur处理。

using UnityEngine;
using System.Collections;
using UnityEngine.UI;
using Common.Base;

public class FrostedGlassPanel : MonoBehaviour {
	private int mScreenx = 0;
	private int mScreeny = 0;

	void Start () {
		mScreenx = Screen.width;
		mScreeny = Screen.height;
		GetComponent<Image>().material = ResourceLoader.LoadResource<Material>("Materials/UIFrostedGlass.mat");
		RefreshBackground();
	}

	void OnEnable(){
		RefreshBackground();
	}

	void RefreshBackground(){
		if(mScreenx <= 0){ 
			//第一次OnEnable时，没有准备好。
			return;
		}

		RenderTexture rt = new RenderTexture(mScreenx/32, mScreeny/32, 0, RenderTextureFormat.ARGB32, RenderTextureReadWrite.Linear);
		Camera.main.targetTexture = rt;
		Camera.main.Render();

		RenderTexture.active = rt;
		Texture2D screenShort = new Texture2D(mScreenx/32, mScreeny/32, TextureFormat.ARGB32, false);
		screenShort.ReadPixels(new Rect(0, 0, mScreenx/32, mScreeny/32), 0, 0, false);
		screenShort.wrapMode = TextureWrapMode.Clamp;//不能用Repeat，否则边缘颜色会相互渗透。
		screenShort.Apply();
		Camera.main.targetTexture  = null;
		RenderTexture.active = null;
		Destroy(rt);

		Sprite sp = Sprite.Create(screenShort, new Rect(0, 0, mScreenx/32, mScreeny/32), Vector2.zero);
		GetComponent<Image>().sprite = sp;
	}
}

using UnityEngine;

using System.Collections;

using UnityEngine.UI;

using Common.Base;

public class FrostedGlassPanel : MonoBehaviour {

private int mScreenx = 0;

private int mScreeny = 0;

void Start () {

mScreenx = Screen.width;

mScreeny = Screen.height;

GetComponent<Image>().material = ResourceLoader.LoadResource<Material>("Materials/UIFrostedGlass.mat");

RefreshBackground();

}

void OnEnable(){

RefreshBackground();

}

void RefreshBackground(){

if(mScreenx <= 0){

//第一次OnEnable时，没有准备好。

return;

}

RenderTexture rt = new RenderTexture(mScreenx/32, mScreeny/32, 0, RenderTextureFormat.ARGB32, RenderTextureReadWrite.Linear);

Camera.main.targetTexture = rt;

Camera.main.Render();

RenderTexture.active = rt;

Texture2D screenShort = new Texture2D(mScreenx/32, mScreeny/32, TextureFormat.ARGB32, false);

screenShort.ReadPixels(new Rect(0, 0, mScreenx/32, mScreeny/32), 0, 0, false);

screenShort.wrapMode = TextureWrapMode.Clamp;//不能用Repeat，否则边缘颜色会相互渗透。

screenShort.Apply();

Camera.main.targetTexture = null;

RenderTexture.active = null;

Destroy(rt);

Sprite sp = Sprite.Create(screenShort, new Rect(0, 0, mScreenx/32, mScreeny/32), Vector2.zero);

GetComponent<Image>().sprite = sp;

}

shader如下：

Shader "Custom/UIFrostedGlass"
{
	Properties
	{
		[PerRendererData] _MainTex ("Sprite Texture", 2D) = "white" {}
		_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
	}

	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
		Pass
		{
		CGPROGRAM
			#pragma vertex vert
			#pragma fragment frag

			#include "UnityCG.cginc"
			#include "UnityUI.cginc"
			
			struct appdata_t
			{
				float4 vertex   : POSITION;
				float4 color    : COLOR;
				float2 texcoord : TEXCOORD0;
			};
			struct v2f
			{
				float4 vertex   : SV_POSITION;
				half2 texcoord  : TEXCOORD0;
				float4 worldPosition : TEXCOORD1;
			};

			v2f vert(appdata_t IN)
			{
				v2f OUT;
				OUT.worldPosition = IN.vertex;
				OUT.vertex = mul(UNITY_MATRIX_MVP, OUT.worldPosition);
				OUT.texcoord = half2(IN.texcoord.x, IN.texcoord.y);				
				return OUT;
			}

			sampler2D _MainTex;
			uniform half4 _MainTex_TexelSize;
			static const half4 curve4[7] = { 	half4(0.0205,0.0205,0.0205,0), 
												half4(0.0855,0.0855,0.0855,0), 
												half4(0.232,0.232,0.232,0),
												half4(0.324,0.324,0.324,1), 
												half4(0.232,0.232,0.232,0), 
												half4(0.0855,0.0855,0.0855,0), 
												half4(0.0205,0.0205,0.0205,0) };
			fixed4 frag(v2f IN) : SV_Target
			{
				half4 blurColor1 = 0;
				for(int i = 0; i < 7; i++){
					blurColor1 += tex2D(_MainTex, IN.texcoord + 0.005 * half2(i-3, 0)) * curve4[i];
				}

				half4 blurColor2 = 0;
				for(int i = 0; i < 7; i++){
					blurColor2 += tex2D(_MainTex, IN.texcoord + 0.005 * half2(0, i-3)) * curve4[i];
				}

				half4 blurColor = (blurColor1 * 0.5 + blurColor2 * 0.5) * 0.9;
				blurColor.a = 1.0;
				return blurColor;
			}
		ENDCG
		}
	}
}