   speed
  i really enjoy learning open gl through this amazing tutorial and i get along with it really great.theres just one problem. the programs run much to fast. is there a general way to reduce speed?i think its not the best way just reducing rotation-values, right?thank you in advance,jerg   
  You should update your rotation using Delta time. You need a function to return the time elapsed since the last frame, and use it something like:Rotation += 0.1f * GetDeltaTime();That will give you a constant rotation speed regardless of the FPS.;  thank you for your quick answer. this idea sounds great.eeehm, my skills just aint good enough to implement it, though i tried doing it on my own, after i found some information about getdeltatime().could someone please be so kind to modify lesson 9's source?   ;  I'm still working on completely new lessons and there everything will take account of the elapsed time. Thus I hope I'll finish the lessons in the next time and show how to do time based animations.   ;  that would be awesome!i'm a little stucked..   