Sometimes it's all about reserving the palette for the start button/system tray. NT was always like that and even WinQuake had NT4 palette issues in the day (and many other Win9x games then didn't support NT for various reasons which may/may not be related to that issue). It's one of the oldest problems that got babby vogons formed

Wasn't that palette problem fixed in one of the Windows 10 updates?

I modified WinQuake and Quake 2 source one day to use 32-bit instead of 8-bit DirectDraw mode and do palette lookup in software. That fixed the problem on Windows 7 (and was a proof that DirectDraw itself is not to blame).
But now on Windows 10 it seems that my patch isn't needed anymore, the original 8-bit color modes work just fine.

The palette problem was already eradicated starting with Windows 8. Stopping explorer.exe is a popular trick on Windows 7 from my understanding, someone also made a program that suspends Explorer, achieving the same effect (don't know why it also mentions Windows 8 and Windows 10, didn't see the problem on these systems). Quite radical workarounds IMO. There's article on PCGamingWiki about this particular problem.

There's also a registry tweak applying some special DirectDraw compatibility flag that might be useful on older OSes, but its effectiveness is limited; alt-tabbing out of the game will undo its effect and the same will happen if the game switches to different video mode at some point. There appears to be at least one more not understood factor affecting it. That's the observed behavior Windows Vista/7 under usual circumstances. On Vista however, you can just leave one Explorer window opened to prevent colors from getting messed up.

Not sure about XP, I remember seeing that problem in the past in Interstate '76 menus when starting it in Glide mode (menus still use DirectDraw), tested Sanitarium demo recently and it looks fine there.

Thanks for everyone's responses! I really appreciate the detailed explanations and links. Interesting to see how explorer.exe can mess up palette allocation/cycling.

That said, in my case, I still find it odd as the particular version of Sanitarium which the Twitch Desktop App provides is the Steam version, which was created by DotEmu (and is likely based on their mobile port of the game). In that case, the game uses SDL2 for rendering, so in theory, SDL2 is handling the game's palettes internally, rather than relying on Windows.

Reading your other thread, you're dealing with an unrelated problem. Might not even be Explorer itself, but some extension plugged into it. Sounds like an isolated, specific case, so this might be a shot in the dark, but ShellExView can show all such extensions. If there's anything non-Microsoft on the list, you may try disabling it and restarting Explorer to see if that helps running the game without having to terminate explorer.exe.

"Sanitarium which the Twitch Desktop App provides "

the twitch desktop app provides games ?

UCyborg wrote:

There's article on PCGamingWiki about this particular problem.

That article (like others) suggests it is a problem specific to "deprecated" DirectDraw, and combined with the fact that many workarounds are DDraw-specific has led people to believe it is a problem with DirectDraw.
This is not the case. It's a problem with paletted 8-bit color modes in general, even if the program does not use DDraw.

32-bit color modes work fine in DirectDraw even on affected systems.

I've seen DirectDraw-to-Direct3D wrappers to fix the problem. Technically, it would be sufficient to make a DirectDraw-to-DirectDraw wrapper that would emulate 8 bpp palette in 32-bit RGB color mode - which I think would be an easier task than those over-engineered wrappers (unless one wants additional graphics effects, shaders etc, or there are other factors).

True. And there aren't "real" 16-bit and 8-bit modes on Windows 8 and up anymore, it's all handled internally in 32-bit mode.

@Azarien
1. DirectDraw is the *ONLY* way to get *EXCLUSIVE* access to the system palette.
DDraw's exclusive access is not exclusive anymore. Hence it is a DDraw bug.

2. DDraw-to-Direct3D wrappers allows for the ~300,000 palette lookups per frame to be GPU accelerated.
This is a performance issue, even in 2018.

This issue reminds me a bit of my DDraw issues with Virtual PC on Win 7..