Experiment with bloom

shader/texture/boxBlur.frag

@@ -19,7 +19,10 @@ const vec2 off[9] = vec2[](
     , vec2( -vOff,0.0 )
     , vec2( -vOff,-hOff )
     );
-
+vec4 combinef (vec4 ac, vec4 bc)
+//{ return vec4 (max(ac.x,bc.x),max(ac.y,bc.y),max(ac.z,bc.z),max(ac.w,bc.w));
+{ return vec4 (max(ac.x,bc.x),max(ac.y,bc.y),max(ac.z,bc.z),ac.w +bc.w*frac);
+}
 void main()
 {
     vec4 sampleTex[9];
@@ -29,6 +32,7 @@ void main()
     }
     vec4 col = vec4(0,0,0,0);
     for (int i = 0; i < 9; i++)
-        col += sampleTex[i] * frac;
+        col = combinef(col,sampleTex[i]);
+        //col += sampleTex[i] * frac;
     fColor = col;
 }