You end up using P/Invoke any time you need to control hardware. In the last few months I needed to use P/Invoke to control cameras, motors, and compute FFTs wi

You end up using P/Invoke any time you need to control hardware. In the last few months I needed to use P/Invoke to control cameras, motors, and compute FFTs with the GPU. You need to use them if you need to control raw GDI objects like bitmaps.