title: How to achieve supersampling / anti-aliasing in pixel shaders?
body: <p>I am trying to write a couple pixel shaders to apply to images similar to Photoshop effects. For example this effect:
  <a href="http://www.geeks3d.com/20110428/shader-library-swirl-post-processing-filter-in-glsl/" rel="nofollow">http://www.geeks3d.com/20110428/shader-library-swirl-post-processing-filter-in-glsl/</a></p>
  
  <p>But I noticed there is aliasing in the resulting image. What can I do to prevent this? I couldn't find any article that explains how to solve this. I read some techniques like rendering in high res and then downsizing the image, but I need to solve this in a pixel shader capacity. But if there is something that could help, I would appreciate it.</p>