Since OpenSceneGraph does not provide binary files for Mac OS X at the time we created our own installer package for Mac OS X 10.5 (Leopard) to get you started faster. (Sorry, if you are running Mac OS X 10.4 Tiger or even older you will have to go through the whole compiling and configuration fun yourself)
Please download and install Xcode Developer Tools from Apple first!
After you downloaded and installed Apple Xcode Developer Tools you can go ahead and download our OSG Installer for Leopard. Just run our OSG Installer and follow the instructions.
Now start Xcode and go to File -> New Project...
Choose Mac OS X - Application in the drawer and then OSG Application
All you have to do now is defining a folder for your project and hitting the Build and Go button!
Congratulations. You should see 2 pyramids now!