GRAPHICS DEVICE INTERFACE

Ø It is the part of the windows that converts the windows graphics function calls to actual commands send to the hardware.

Ø GDI is a program file called GDI.EXE or GDI32.DLL and stored in windows System Directory.

Ø Windows environment loads GDI.EXE into memory when it is needed for graphical output.

Ø Provides all the basic drawing functionality for windows.

Ø Provides a layer of abstraction that insulates applications from the trouble of drawing directly to hardware by calling appropriate device driver in response to windows graphics function call.

Ø The GDI functions are directly build right into MFC device context classes as device context member functions. (classes likeCClientDC, CPaintDC, CWindowDC(), CMetaDC all derived from CDC)