Mirror

[This is preliminary documentation and subject to change.]

SUMMARY

This sample demonstrates how to use a driver to perform video mirroring. When video mirroring is active, each time the system draws to the primary video device at a location inside the mirrored area, a copy of the draw operation is executed on the mirrored video device in real time. With this mirroring scheme, you can simultaneously draw the same output to several video devices. Since the driver allocates memory dynamically for targets, the number of displays that your system can support depends on how much free memory you have at mirror-time.

This sample is designed to provide information on a standard, generic method of mirroring. This eliminates the need for special case-by-case solutions which were used before this support was added to the system. The sample runs only on the Microsoft® Windows® 2000 platform. It features commented source code that documents in detail how the code works, to make it easy to modify and extend. Please note that this is the first version of the video mirror sample. Additional functionality may be added to the sample in future releases.

The sample is comprised of three pieces:

• The display driver, in \Ntddk\Src\Video\Displays\Mirror\Dll.
• The video miniport driver, in \Ntddk\Src\Video\Miniport\Mirror. The miniport driver included here is a skeleton. It simply returns success status for all miniport calls made by the system as there is no real hardware controlled by the mirror sample.
• An application that is a sample user-mode service, in \Ntddk\Src\Video\Displays\Mirror\App.

BUILDING THE SAMPLE

Install the driver by using the included .ini file, then run the sample application. The application will attach the driver to the desktop, and mirroring will be active. At present, the sample application is a command-line Win32 program.