Gaussian blur shader

/// Vertex (vsh)
// ATTRIBUTION: This shader uses elements from DukeSoft's "Simple bloom shader"
// which can be found here (https://marketplace.yoyogames.com/assets/4729/simple-bloom-shader).

//
// Simple passthrough vertex shader
//
attribute vec3 in_Position;                  // (x,y,z)
//attribute vec3 in_Normal;                  // (x,y,z)     unused in this shader.
attribute vec4 in_Colour;                    // (r,g,b,a)
attribute vec2 in_TextureCoord;              // (u,v)

varying vec2 v_vTexcoord;
varying vec4 v_vColour;

void main()
{
    vec4 object_space_pos = vec4( in_Position.x, in_Position.y, in_Position.z, 1.0);
    gl_Position = gm_Matrices[MATRIX_WORLD_VIEW_PROJECTION] * object_space_pos;

    v_vColour = in_Colour;
    v_vTexcoord = in_TextureCoord;
}

/// Fragment (fsh)
varying vec2 v_vTexcoord;
varying vec4 v_vColour;
uniform vec3 size;//width,height,radius
uniform float blurSize;
uniform float intensity;

const int Quality = 8;
const int Directions = 16;
const float Pi = 6.28318530718;//pi * 2

void main()
{
     vec4 sum = vec4(0);
   int j;
   int i;

   // take nine samples, with the distance blurSize between them
   sum += texture2D(gm_BaseTexture, vec2(v_vTexcoord.x - 4.0*blurSize, v_vTexcoord.y)) * 0.05;
   sum += texture2D(gm_BaseTexture, vec2(v_vTexcoord.x - 3.0*blurSize, v_vTexcoord.y)) * 0.09;
   sum += texture2D(gm_BaseTexture, vec2(v_vTexcoord.x - 2.0*blurSize, v_vTexcoord.y)) * 0.12;
   sum += texture2D(gm_BaseTexture, vec2(v_vTexcoord.x - blurSize, v_vTexcoord.y)) * 0.15;
   sum += texture2D(gm_BaseTexture, vec2(v_vTexcoord.x, v_vTexcoord.y)) * 0.16;
   sum += texture2D(gm_BaseTexture, vec2(v_vTexcoord.x + blurSize, v_vTexcoord.y)) * 0.15;
   sum += texture2D(gm_BaseTexture, vec2(v_vTexcoord.x + 2.0*blurSize, v_vTexcoord.y)) * 0.12;
   sum += texture2D(gm_BaseTexture, vec2(v_vTexcoord.x + 3.0*blurSize, v_vTexcoord.y)) * 0.09;
   sum += texture2D(gm_BaseTexture, vec2(v_vTexcoord.x + 4.0*blurSize, v_vTexcoord.y)) * 0.05;

   // take nine samples, with the distance blurSize between them
   sum += texture2D(gm_BaseTexture, vec2(v_vTexcoord.x, v_vTexcoord.y - 4.0*blurSize)) * 0.05;
   sum += texture2D(gm_BaseTexture, vec2(v_vTexcoord.x, v_vTexcoord.y - 3.0*blurSize)) * 0.09;
   sum += texture2D(gm_BaseTexture, vec2(v_vTexcoord.x, v_vTexcoord.y - 2.0*blurSize)) * 0.12;
   sum += texture2D(gm_BaseTexture, vec2(v_vTexcoord.x, v_vTexcoord.y - blurSize)) * 0.15;
   sum += texture2D(gm_BaseTexture, vec2(v_vTexcoord.x, v_vTexcoord.y)) * 0.16;
   sum += texture2D(gm_BaseTexture, vec2(v_vTexcoord.x, v_vTexcoord.y + blurSize)) * 0.15;
   sum += texture2D(gm_BaseTexture, vec2(v_vTexcoord.x, v_vTexcoord.y + 2.0*blurSize)) * 0.12;
   sum += texture2D(gm_BaseTexture, vec2(v_vTexcoord.x, v_vTexcoord.y + 3.0*blurSize)) * 0.09;
   sum += texture2D(gm_BaseTexture, vec2(v_vTexcoord.x, v_vTexcoord.y + 4.0*blurSize)) * 0.05;

    vec2 radius = size.z/size.xy;
    vec4 Color = texture2D( gm_BaseTexture, v_vTexcoord);
    for( float d=0.0;d<Pi;d+=Pi/float(Directions) )
    {
        for( float i=1.0/float(Quality);i<=1.0;i+=1.0/float(Quality) )
        {
                Color += texture2D( gm_BaseTexture, v_vTexcoord+vec2(cos(d),sin(d))*radius*i);
        }
    }
    Color /= float(Quality)*float(Directions)+1.0;
    gl_FragColor =  (sum * intensity + Color) *  v_vColour;
}