模糊的原理：像周圍的借取顏色，放到本畫素。不同的模糊效果是採用不同的去顏色位置和演算法。徑向模糊原理是沿著某方向取顏色，而扇形徑向則是沿著扇形的切線方向取色。

sampler2D RT : register(s0);

///////////////////////////////////入口函式
float4 Distortion_ps(//in float4 pos : POSITION,
                     float2 iTexCoord : TEXCOORD0,

                     ) : COLOR
{
        float4 co=float4(0); 
        ///////徑向模糊
        float2 dir
 
=float2(0.5,0)-iTexCoord;
        float dist=length(dir);
        dir/=dist;
        float3 dirDot=cross(float3(0.5,0,1),float3(dir.x,dir.y,0));
        //normalize(dirDot);
        dir=float2(dirDot.x,dirDot.y);
        dir=dir/(length(dir));
        dir*=0.35*dist;//模糊程度與距離中心的長度相關

        float4 sum =float4(0
 
); 
        sum= tex2D(RT, iTexCoord);
        sum +=tex2D(RT, iTexCoord - dir*0.01)*0.8;  
        sum += tex2D(RT, iTexCoord - dir*0.02)*0.6;  
        sum += tex2D(RT, iTexCoord - dir*0.03)*0.5;  
        sum += tex2D(RT, iTexCoord - dir*0.04)*0.3;  
        sum += tex2D(RT, iTexCoord - dir*0.05)*0.1;  
        sum += tex2D(RT, iTexCoord + dir
 
*0.01)*0.8;  
        sum += tex2D(RT, iTexCoord + dir*0.02)*0.6;  
        sum += tex2D(RT, iTexCoord + dir*0.03)*0.5;  
        sum += tex2D(RT, iTexCoord + dir*0.04)*0.3;  
        sum += tex2D(RT, iTexCoord + dir*0.05)*0.1;  

        sum /= 5.6;  
        co=sum;



     co.a=1;
    return co;
}