The difference between SS and SC prefixed mix files.

[Blade]

I've been looking at the code of RA with a lot of assistance from CCHyper and I believe I understand the difference of how these files are loaded and why it appears that the SS prefixed files prevent the loading of files within them (assuming the system is the same in C&C). For many of the image file types (font, shp and such), the mix file must be cached entirely to memory as the loading system just asks for a pointer offset into the cached mix file rather than trying to actually read it from disk and the loading system does not fall back to allocating memory itself for uncached files. If the mix file that contains the file is not a cached file, then no pointer is returned and the game continues on as though the file wasn't present, but the locating system will think it found the file and look no further. The difference then is that SS files are loaded but not cached and SC files are loaded and cached. SS files should work fine for file types that are not retrieved as pointer but instead are opened as files. Which files are those you ask? Err, I'll get back to you on that one

[Nyerguds]

CCHyper told me that the fact the ss*.mix files prevent file loading in C&C1 is most likely a bug, actually. I honestly don't know if any files at all are loaded "as files" from the mix... I never looked into what kinds of different file retrieval functions there are.

 

Though I've (ab)used that system in the 1.06c patch as updates system to make the hospital unsellable, by preventing the game from loading its build-up animation

[Blade]

From the looks of RA, only scores and movies1/2 and the enclosing container mix files (redalert.mix and main.mix) aren't loaded as cached so I'll go out on a limb and say only themes and movies in theory work from ss*.mix files.

[Nyerguds]

Hmm. That could be right. They get refreshed somehow in the CD loading/checking system.

[Iran]

Yeah that's true, only movies and videos aren't cached.