title: iOS 5 undeclared identifier GL_TEXTURE_RECTANGLE
body: <p>I'm having trouble using a rectangular texture on iOS (iPhone 3gs or newer)</p>
  
  <p>I'm trying to use <code>GL_TEXTURE_RECTANGLE</code> and/or <code>GL_EXT_texture_rectangle</code> but XCODE autocomplete doesn't recognize it, i think because the proper header file is not imported and throws me the <code>undeclared identifier</code> error.</p>
  
  <p>Also tried <code>GL_ARB_texture_non_power_of_two</code> and <code>GL_ARB_texture_rectangle</code> as answered in this question <a href="https://stackoverflow.com/questions/6883160/opengl-es-gl-texture-rectangle">OpenGL ES GL_TEXTURE_RECTANGLE</a> but none are declared.</p>
  
  <p>I've googled and haven't found a reference to the header it is declared, the header files used in the documentation sample projects are not found.</p>
  
  <ul>
  <li>Working on xcode 4.2</li>
  </ul>
  
  <p>these are the headers I'm currently importing:</p>
  
  <pre><code>#import &lt;OpenGLES/EAGL.h&gt;
  #import &lt;OpenGLES/ES1/gl.h&gt;
  #import &lt;OpenGLES/ES1/glext.h&gt;
  #import &lt;OpenGLES/ES2/gl.h&gt;
  #import &lt;OpenGLES/ES2/glext.h&gt;
  </code></pre>
  
  <p>also tried to import these </p>
  
  <pre><code>#import &lt;OpenGL/OpenGL.h&gt; //file not found
  #import &lt;OpenGL.h&gt; //file not found
  #import &lt;OpenGL/glu.h&gt; //file not found
  </code></pre>