title: glEnable(GL_TEXTURE_GEN_S) GL_INVALID_OPERATION
body: <p>I'm currently working on a shadow Mapping thing. I found Paul's Projects <a href="http://www.paulsprojects.net/tutorials/smt/smt.html" rel="nofollow">http://www.paulsprojects.net/tutorials/smt/smt.html</a>, and I'm currently trying to implement this. But I'm not able to get a proper solution.</p>
  
  <p>Does anyone of you guys have any idea why putting a glPushMatrix(), glPopMatrix() pair for each glmodelview- and glprojection-matrix around the whole drawing process (all 3 necessary shadow-pathes) would cause any GL_INVALID_OPERATION problem when calling glEnable(GL_TEXTURE_GEN_S)?</p>
  
  <p>The error analysis for glEnable(GL_TEXTURE_GEN_S) sais that in the current state glEnable(GL_TEXTURE_GEN_S) can not be executed. Any ideas?</p>