So I have a class which contains a function that I would like to use in another project. I am 100% positive that it is possible and have seen it done, which might be because of std::shared_ptr<class to share> but am not positive. How would I call functions from a class in another project with out getting external symbol errors.
P.S. I have already referenced and added includes to what needs to be added, the problem is to do with actually calling the function in the class. For example I can put a "float i = 10" and call for "i" easily but when I call for "vec2 CheckMousePos()" is gives me an external symbol error
What you want to do is place the function in a separately compiled file. You would create a .h file with the header declarations for your shared function(s). Include the new .h file in both projects. Compile the .cpp file for your function into a .o file, then include the .o file in both projects. If you have a number of shared functions, you can create a .lib file. Details of including the .o or .lib file in your project depend on what IDE you're using. In Visual Studio, there is a property page that allows you to specify additional object or library files. Other IDEs should be similar.