title: libgdx texture filters and mipmap
body: <p>When I try to use mipmap filtering in LibGDX, none of the images appear.  </p>
  
  <p>I'm new to LibGDX, and I have a simple 2d scene with three rotating, scaled circles.  In order to anti-alias them, I wanted to use linear filtering.  For advice, I looked to <a href="http://www.badlogicgames.com/wordpress/?p=1403" rel="noreferrer">this article</a>,which said that, for heavily scaled images, a mipmap can be used to improve speed or quality.</p>
  
  <p>The first unexpected appearance was that, despite the fact that all of my images were scaled down, I would only see a linear filter if the magFilter was linear. In other words:</p>
  
  <p><strong>This code will show a linear filter for minified images:</strong></p>
  
  <pre><code>parentTexture.setFilter(TextureFilter.Nearest, TextureFilter.Linear);
  </code></pre>
  
  <p><strong>whlie this code will not:</strong></p>
  
  <pre><code>parentTexture.setFilter(TextureFilter.Linear, TextureFilter.Nearest);
  </code></pre>
  
  <p><strong>which seems opposite to the libGDX function:</strong></p>
  
  <pre><code>void com.badlogic.gdx.graphics.Texture.setFilter(TextureFilter minFilter, TextureFilter magFilter)
  </code></pre>
  
  <p>This would not bother me, except that it indicates that either libgdx is wrong (unlikely), the article is wrong (unlikely), or I don't understand texture filters.  The latter seems especially likely when I try mipmap filters.</p>
  
  <p><strong>This code causes nothing to display</strong></p>
  
  <pre><code>parentTexture.setFilter(TextureFilter.MipMapLinearLinear, TextureFilter.Linear);
  </code></pre>
  
  <p><strong>This code displays, but with nearest filtering</strong></p>
  
  <pre><code>parentTexture.setFilter(TextureFilter.Linear, TextureFilter.MipMapLinearLinear);
  </code></pre>
  
  <p>Any explanation of where I'm wrong would be greatly appreciated.  I have searched elsewhere,  but texture filters in libGDX is pretty specific, so aside from the article, I haven't found much to help.</p>