What I actually ended up doing was make the window 1x1 pixel, undecorated, and position at -50,-50. I tried make it show up under a 2d gui (wxWidgets) splash screen, but even setting setZOrder(WindowProperties.ZBottom) still makes it flash in front of the splash screen for a second. The real reason I’m so paranoid is because I have this persistant splash screen (so that the windows desktop is never visible) displayed by a non-panda launcher application that runs panda games and I want as smooth a transition as possible between that screen and the same image display in panda that panda then fades out into the actual game and fades back at the end.
What I really need then (what I’m guessing you were hinting at) is something like the setParentWindow function that I hear is coming the next version so that I can display panda in the same window the launcher uses.
Although, ideally I wouldn’t have a launcher program running subprocesses of panda, I’d have a panda launcher that loads classes that represent games and a way to completely clear and reset the scene graph and other panda managers and things between games. I’ll probably be making a forum post about that at a later date since this isn’t the first project I’ve wanted something like separate panda contexts for (although it is the first time I’ve actually tried to do it and failed).