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Avoiding the Linker Error: Instance already defined?
This seems to be caused because you've got variables in each of those objects with the same name. So inside your WinMain.cpp you'll have bool gameRun; and then another copy of that inside UGE.h.
If you want to have them all the same variable with the same value. You can put it inside a Singleton object that everybody can request from.
e.g
http://en.wikipedia.org/wiki/Singleton_pattern
Or, you can define it in 1 location and have the other locations pre-fixed with "extern" so they use the single declaration from elsewhere; thus it's a global variable. This approach isn't recommended because you cannot encapsulate the variable and anyone has read/write access to it with no controls. It also makes it hard for you determine what code has modified it; Using a singleton allows you to debug on the method call to change it etc.
If you want to have them all the same variable with the same value. You can put it inside a Singleton object that everybody can request from.
e.g
Configuration::instance().getGameRun();http://en.wikipedia.org/wiki/Singleton_pattern
Or, you can define it in 1 location and have the other locations pre-fixed with "extern" so they use the single declaration from elsewhere; thus it's a global variable. This approach isn't recommended because you cannot encapsulate the variable and anyone has read/write access to it with no controls. It also makes it hard for you determine what code has modified it; Using a singleton allows you to debug on the method call to change it etc.
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