//径向模糊

CCEffect %{
  techniques:
  - passes:
    - vert: vs
      frag: fs
      blendState:
        targets:
        - blend: true
      rasterizerState:
        cullMode: none
      properties:
        texture: { value: white }
        u_point: { value: [0.5, 0.5] }
        u_resolution: { value: [1280, 720] }
        u_Strength: { value: 0.125 }
}%

CCProgram vs %{ // 顶点Shader模块开始
  #include <cc-global>
  precision highp float;	  //定义float高精度
	in vec3 a_position; // 顶点Shader 从渲染管道里面获取的顶点信息,使用attribute来修饰;
	in vec2 a_uv0;   // 纹理坐标;
	out vec2 uv0;     // 传递给着色Shader，varying 来修饰，进行插值
	void main () {
		gl_Position = cc_matViewProj * vec4(a_position, 1);
		uv0 = a_uv0;
	}
}%

CCProgram fs %{
  precision highp float;
  in vec2 uv0;
  uniform sampler2D texture;
  uniform ARGS{
    vec2 u_resolution;
    vec2 u_point;
    float u_Strength;
  };
  void mainImage( out vec4 fragColor, in vec2 fragCoord )
  {
      // const float u_Strength = 0.125;    
      const int Samples = 64; //multiple of 2
      vec2 uv = fragCoord.xy;
      vec2 dir = (fragCoord.xy-u_point.xy);
      vec4 color = vec4(0.0,0.0,0.0,0.0);
      for (int i = 0; i < Samples; i += 2) //operating at 2 samples for better performance
      {
          color += texture2D(texture,uv+float(i)/float(Samples)*dir*u_Strength);
          color += texture2D(texture,uv+float(i+1)/float(Samples)*dir*u_Strength);
      }   
      fragColor = color/float(Samples);
  }
      
  void main(void)
  {
      mainImage(gl_FragColor, uv0);
  }
}%