title: Is opengl cross platform? If not, how a game be ported?
body: <p>Ok, so say I'm writing a game in c++ with opengl. The game draws a few, simple shapes like squares on the screen. Now say I want to run the "game" on windows. How would I go about porting it? The actual c++ wouldn't be the problem, as it can be recompiled to fit the environment from what I understand. But the calls to the openGL library would be broken wouldn't they? The actual opengl library which would be included for development woul be compiled for the os, which would necessitate redownloading the library, which would lead to modifications to the source. Which would break the program on the original environment, right?</p>
  
  <p>tl;dr Is there any way to build an opengl game for multiple operating systems without having to modify the source code to be platform specific or downloading external wrappers or libraries?</p>