Displaying another application on top of a directdraw full screen application

Question

I am using a Full Screen application that is using DirectDraw functions for display and it is working fine. Now I want to show another application with its own window but the other application is hidden behind the full screen Direct Draw application when launched. I can access the other application only when I close the directdraw full screen application.

Is it possible to switch to another application from a direct draw full screen application while running? Is there any way we can display the other application’s window on top of the full screen DirectDraw function and then resume back once the other window is closed?

Thanks and regards

Answer 1

I looked into this some time ago and found that the way its done is to hook the DirectDraw APIs and insert your own rendering in there. Basically, after the other app is done drawing the scene and is about to present the backbuffer, your code jumps in and does its own thing. I never got it working myself, but that seems to be the approach. I don't think there's any 'easy' way to do it though.

One other option would be to see if the other app can run in fullscreen windowed mode. Basically, no borders, filling the whole screen, but not technically fullscreen/exclusive mode. If it supports that, then you can make a topmost window which will display over top of it.