Hello, As always, I know this community has much more knowledge then I can find through any of my library's books, so here I go: I've been working on a game engine (Who isn't here? ha) in unmanaged C/C++ in DirectX 9. Though I feel comfortable with DX, I find it very messy, somewhat clunky to wrap into abstracted functions, and overly complex. I've decided to move to OpenGL, but I'm still unclear on three topics: Performance, the 3.0 version API / external API, and cross-platform development. Any help or answers for my below questions is very, and always, appreciated! Performance: From what I understand OpenGL wraps the hardware interface more cleanly that DX, is this true? If so, would I be loosing performance or is taht negligible? 3.0 API/3rd Party: I've heard of the new OpenGL 3.0 API set. I've tried to find some documentation but can't find anything that is very clear. Is this out yet, and if so should I target 3.0 or target 2.1? Also, I keep hearing about these smaller 3rd party libraries such as GLUT, but what exactly are their purpose? Cross-Platform Development: Naturally some parts of code must be written in different ways for different OS, especially the window management, but what about standard input? Is there a built-in standard keyboard/mouse interface in OpenGL? As I've said above, I really appreciate any and all help. Thank you!

Thank you,

This definitely helps clear up a few of my questions. Much appreciated!

A/ performance with opngl should be a bit better than d3d, carmack mentioned ~5%, but it depends on what sort of app youre doing
B/ keep in mind a lot of cards (eg mine) dont support ogl3.0, glut/sdl just help setting up the window/handle input etc
C/ I use SDL very stable multi platform window manager, use it + your app should run on the mac/linux/windows without any changes