Tech Support > Microsoft Windows > Drivers > Mirror driver -> virtual display driver
Mirror driver -> virtual display driver
Posted by Geza Soos on November 28th, 2004


Hi!

I tested the sample Mirror Driver comes from MS DDK, and it worked
perfectly, but it is not exacly what i would like.

The goal is to create a 'virtual display dirver' where i can extend my
desktop, and it appears on Display Properties -> Settings tab as
secodnary monitor.

Can anybody tell me what i need to modify in the Mirror Driver sample
to appears as a stand-alone display driver?

Thank you

Posted by Lev Kazarkin on December 7th, 2004


Hello, Geza!

GS> Can anybody tell me what i need to modify in the Mirror Driver
GS> sample to appears as a stand-alone display driver?

I see no problem converting mirror driver to virtual video device.
You have to
--Remove all evidence of its mirror heritage:
-- "MirrorDriver" registry value from Inf (and from registry),
-- GCAPS_LAYERED flag from DEVINFO::flGraphicsCaps;
-- Add the functionality required for a usual video driver to the
miniport, including support for video mode information;
-- Add DrvGetModes to display module.

It is also a good idea to add a basic support for DirectDraw.

Of course, to be functional, your driver have to implement some sort
of rendering for required DDIs. And a reliable mechanism
of communication to the program that mediates the screen image
to its real consumers.
For example, you may share the screen surface memory with
a client application/service and provide some messaging
to tell the application that there is a change on the screen.

--------------------
Lev Kazarkin
Mirror drivers. Consulting and custom development.
http://www.demoforge.com
E-mail: mirrdrv@demoforge.com