I've ran in to an odd issue with my Unity3D game completely pausing in certain scenarios, even with the Run In Background player setting on.
For reference I'm on Windows 7 Ultimate using Unity 4.3.3
In The Editor: If I tab out of the editor while the game is running everything keeps working fine.
*In Windowed Mode:* If I'm running the standalone in windowed mode and tab out, everything keeps working fine.
However, if I grab the top bar on the window to move the window around, the game pauses until I release the window. Nothing updates, nothing runs while it's paused.
In Fullscreen Mode: If I'm running the standalone in fullscreen mode and alt+tab out the game pauses. Not resuming until I tab back in to the game.
This is causing issues with the multiplayer aspects of my game, because the client stops sending messages to the server whenever they alt+tab out or move the window.
I know the graphics device is getting lost when I tab out, because I get this error in my log:
HandleD3DDeviceLost HandleD3DDeviceLost: still lost Skipped rendering frame because GfxDevice is in invalid state (device lost)
But that should only cause the game to stop rendering, which is fine. I just need the update loop to continue.