title: three.js: how to add CopyShader after FXAAShader (r58)
body: <p>In postprocessing, I added CopyShader after FXAAShader, for proper rendering even if FXAA are disabed (like a example: webgl_postprocessing2.html).</p>
  
  <pre><code>~
  
  renderer.setSize( 320, 240 );  // not full screen
  
  ~
  
  fxaa = new THREE.ShaderPass( THREE.FXAAShader );
  fxaa.uniforms[ 'resolution' ].value = new THREE.Vector2( 1 / 320, 1 / 240 );
  composer.addPass( fxaa );
  
  var effect = new THREE.ShaderPass( THREE.CopyShader );
  effect.renderToScreen = true;
  composer.addPass( effect );
  </code></pre>
  
  <p>This code doesn't work well and the rendered image is smaller than expected.</p>
  
  <p>I'm using r58 and confirmed with Firefox20. What should I do?</p>