compiling multiple cpp files

Question

I am writing c++ in notepad++ using nppexec plugin and compiling with minGW.

I have a folder structure of:

projckt/
- main.cpp
- head/
-- vtk.h
- src/
-- vtk/
--- vtkFile1.cpp
--- vtkFile2.cpp

How do I compile and link? For my "hello world" scripts I used:

npp_save
cd "$(CURRENT_DIRECTORY)"
g++ $(FILE_NAME) -std=c++11 -o $(NAME_PART)
NPP_RUN $(NAME_PART)

This works fine, I want a solution where I don't have to add a new .cpp file to the command when I create one. I have tried:

npp_save
cd "$(CURRENT_DIRECTORY)"
g++ *.cpp -std=c++11 -o $(NAME_PART)
NPP_RUN $(NAME_PART)

It seems that the .cpp files in the sub directories is not included. Is there a way similar to copying subtree folders in unix cp -r.