title: cocos2d-x - Apply blur to transparent LayerColor
body: <p>I have investigated how the blur shader is applied to sprite in tests of <code>cocos2d-x</code> (<code>ShaderTest/ShaderTest2.cpp</code>). </p>
  
  <p>Now my problem is a bit different: I have a layer initialized as follows:</p>
  
  <pre><code>LayerColor::initWithColor(Color4B(0, 0, 0, 180)
  </code></pre>
  
  <p>So it is black but transparent. My intention is to show the content under the layer but with bad visibility. </p>
  
  <p>Now I need to add a blur effect to make visibility under my <code>ColorLayer</code> even worse. </p>
  
  <p>My first question is how I can do that? 
  The second why <code>cocos2d-x</code> does not support such simple and vastly used effects such blur is without using shaders?</p>
  
  <p>P.S. I use<code>cocos2d-x 3.0</code>.</p>