Draw a triangle on OSX.

First and for most, install tools or packages below:

XCode, this one must be installed.
glfw, $ brew install glfw
glew, $ brew install glew
cmake, we use it to build this project.

Once you have installed Xcode, glew, glfw, cmake, JUST run cmake:

$ mkdir build
$ cd build
$ cmake ..
$ make

Then you'll have the Executable Jupiter, just run:

$ ./Jupiter

And you'll see a white triangle in the window.

Since you have this basic development environment, just go on with OpenGL and do anything you want.