title: Converting isometric coordinates
body: <p>I decided to make a isometric game using c++ and cocos2d-x.
  Each isometric tile has an X and an Y coordinate, incresing 1 per tile moved. This is how I am converting tile to screen coordinates.</p>
  
  <pre><code>cocos2d::CCPoint WorldPos::convertToScreen(){
      cocos2d::CCPoint posScreen;; 
      posScreen.x=(this-&gt;x)*(TILE_WIDTH/2) + (this-&gt;y)*-TILE_HEIGHT;
      posScreen.y=(this-&gt;x)*(TILE_HEIGHT/2) + (this-&gt;y)*(TILE_HEIGHT/2);
  
      return posScreen;
  }
  </code></pre>
  
  <p>The tiles are all 40px wide and 20px tall.</p>
  
  <p>now I need a function to convert these world coordinates (the isometric coordinates) back to screen coordinates. something like </p>
  
  <pre><code>WorldPos* WorldPos::convertToWorld(cocos2d::CCPoint &amp;point)
  </code></pre>
  
  <p>I can't seem to figure this one out, am I doing it all wrong and should I do positioning is a diffirent way or is there some kind of calculation that I can't figure out?</p>