INFO: GDI Simulation Routines and Device Drivers for Windows

SUMMARY

The following information concerns GDI's simulation routines for device drivers:

GDI discards its simulation routines when more intelligent drivers provide the required information. GDI is demand-loadable and discardable. When a smart driver registers its capabilities with GDI, GDI dumps the simulation routines that it uses for less intelligent display drivers. For example, when writing a driver that can handle all the OUTPUT functions, GDI will avoid loading all the simulation routines.

In addition, GDI's simulation routines are optimized. However, it is usually the case that device drivers can complete output functions a lot faster because no GDI object or memory must be allocated during the operations, and device drivers can deal directly with the hardware device.