   Texture + Blending problem
  I have following problem. All textures on the scene have diagonal line:This problem occurs ONLY on old videocards (GeForce * 64Mb).I have found the solution. If I disable:  glEnable(GL_BLEND);  glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);blending, all becomes ok. What can be the problem?   
  do u have polygon smooth enabled?also u should always disable blending when u dont need it (like for the above picture), as its much slower than a non blended polygon   ;  Yes, I have polygon smooth enabled. Is it bad or good in this situation? Full code of primary initialization:  glShadeModel(GL_SMOOTH);  glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);  glHint(GL_LINE_SMOOTH, GL_NICEST);  glEnable(GL_POLYGON_SMOOTH);  glEnable(GL_LINE_SMOOTH);    /* glEnable(GL_BLEND);  glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); */  glClearDepth(1);  glEnable(GL_DEPTH_TEST);  glDepthFunc(GL_LEQUAL);  glEnable(GL_SCISSOR_TEST);  glLightfv(GL_LIGHT0, GL_POSITION, @light0_pos);  glLightModelfv(GL_LIGHT_MODEL_AMBIENT, @lmodel_ambient);  glLightModeli(GL_LIGHT_MODEL_TWO_SIDE, 1);  glEnable (GL_LIGHTING);  glEnable (GL_LIGHT0);  glEnable(GL_NORMALIZE);;  polygon smooth is an old method of doing AA, thus i wouldnt encourage it (ie disable it)if u want AA looking multisample, this is hardware accelarted with most cards, thus faster + should look better   ;  On modern cards I have enabled multisampling. But I need my application to run on old cards, but I got this problem with line. It's because of blending. If I disable it problem goes away.   ;  thats cause disabling the blending also disables polygon_smooth (ie polgon smooth needs bledning enabled to work)   