title: LibGDX Straight line is invisible
body: <p>I'm trying to draw a grid in libgdx, but I can't, becasue when I draw a striaght line it's invisible, O_O</p>
  
  <pre><code>public static void draw(ShapeRenderer render) {
      render.setColor(Color.WHITE);
      render.begin(ShapeType.Line);
      for(int r = 0; r &lt; gridTiles.length; r++) {
          for(int c = 0; c &lt; gridTiles[0].length; c++) {
              gridTiles[r][c].draw(render);
          }
      }
      render.end();
  }
  </code></pre>
  
  <p>The draw() method</p>
  
  <pre><code>public void draw(ShapeRenderer render) {
      render.line(10, 10, 64, 10); // Invisible
  }
  </code></pre>
  
  <p>however, if I change it to be slightly offset and not straight like</p>
  
  <pre><code>render.line(10, 10, 64, 9); // Visible
  </code></pre>
  
  <p>It becomes visible. </p>