title: openGL moving camera
body: <p>I m trying to move my camera. I am using gluLookAt function. I have some variables for this. </p>
  
  <pre><code>float x,y,z ==&gt; is camera location
  float lx,ly,lz ==&gt; is point that camera looks.
  </code></pre>
  
  <p>I try to move on x axis</p>
  
  <pre><code>x= x+0.01
  gluLookAt(x,y,z, lx,ly,lz, 0.0 1.0, 0.0);
  </code></pre>
  
  <p>it is work. </p>
  
  <p>When i try to move on z axis as same as above</p>
  
  <pre><code>z = z +0.01
  gluLookAt(x,y,z, lx,ly,lz, 0.0 1.0, 0.0);
  </code></pre>
  
  <p>nothing  change. Also when i invoke this function several times, first half of object dissapear (corners of object) and after next calling gluLookAt object dissapear completely.</p>
  
  <p>I want the object looks bigger when camera move forward and smaller when camera move backward. But any changes is occured when i move camera on z axis.</p>
  
  <p>What is the problem? Why object dissapear? How can i achieve that object get bigger when moving camera forward.</p>
  
  <p>I know i can solve it by glTranslate or increasing size of object. But i want to use  gluLookAt.</p>
  
  <p>Thanks you for answers.</p>