   OpenGL ease of learning?
  A friend told me OpenGL was pretty easy to learn and use.  I have done a little DirectX and I was wondeirng what makes OpenGL easier to learn or easier to use?   
  Difficulty of learning is fairly personal.  I will say for me and my best programming friend, we find OpenGL way easier to think in for BASIC 3D type stuff than DirectX (and we both had DirectDraw and DirectSound experience).  I have no idea if it stays any easier when more complicated stuff arises (probably not - because Direct3D has some nice utility functions), but it did help me learn 3D concepts.I loved the red book.  Buy it.   ;  your friend is in right, opengl is really easy to learn. It has nice and consistent API. Neither it have too mayn toy-abstractions layered over each another.   ;  I have no DirectX eperience, but I found OpenGL pretty easy to start using and understand. Either way, get a good book. They make it soo much easier.   ;  Quite frankly, neither API is really very dificult, although each has its own methodology.The dificult part (if you don't already have it), is a very solid grounding in 3 dimensional math (Vectors, matrices, quaternions, coordinate systems, etc.).   