Random update(s)

Well, I'd feel really bad if I didn't update this blog with something! =) So I thought I'd at least do a few quick things for Cxbx. Since it's on my resume, keeping it updated would help.

Even though the above screens aren't all to impressive, those two games have been driving me crazy as of late and getting it to do something is better than what it was doing before. Which leads me to another thing I wanted to bring up. Patrickvl and defiance have been talking about fixing how we emulate Critical Sections in Cxbx. So far, it appears to be a rather big problem for this emulator. Patrickvl did manage to fix a few things with Enter/LeaveCriticalSection() (hence the reason Dxbx does a better job of emulating Rayman Arena right now) and if I can get in touch with him and discuss how he fixed it, then we will see a lot more games working on Cxbx. Since I'm a noob to how critical sections work (I've never used that feature before), I'll have to further educate myself on the subject just in case I have to figure this out on my own. After taking a look myself, the big thing is that it just appears that the main problem is that the structures differ from the Xbox to the PC version. This is bad, but either way, it should be emulated correctly. For now, I guess I could just keep track of each critical section created (just like how Cxbx keeps track of every IDirectSoundBuffer* pointer created) and just save the valid params for each critical section. If this works, then it should solve problems with various games such as Blood Wake, Rayman Arena, Taz: Wanted and Zapper and possibly more. I'm assuming this will work, until I try it tonight, we'll see.

As of late, I've noticed that we've had some rather "problematic" kernel functions preventing numerous games from working correctly. One of the most notorious of those functions is NtQueryFileAttributes. Instead of dealing with that pain-in-the-ass-to-emulate function, instead I created a signature and emulated it on a higher level using the native GetFileAttributesA() function. I did this when working games such as Dues Ex and Hunter the Reckoning and it worked like a charm.

"Why haven't you updated the SVN yet if you've done all this and more?" Good question. That's because I have a bit of bad news. First of all, I was tracking down some bad DirectSound signatures for XDK 3911 when working on Blood Wake. I commented those out and was planning on fixing them later (not really a problem to fix actually), but upon doing that, I broke Halo. I assume most of you don't care about that, but it does get worse. My latest build broke Turok! Why? I don't know yet. All I know is that there's NULL surface causing the crash. I can add sanity checks to get around that, but not sure if it's a major problem. My debugging skills really suck, and so far I've been relying on other team members to help me debug stuff. That needs to change, and fast!

One more thing, I know that you guys want to play games like Conker, Midtown Madness 3, Unreal Championship II, and other games using the D3D8LTCG library. Well, I have some more bad news for you. When I was working on adding further support for this library, I did get some of the XDK samples built under the LTCG release to work, however, the code inside these functions are dynamic, NOT static like with normal D3D8 library builds. What does this mean? It means that even though one signature might work for one app/game, it's not guaranteed to work for the next as the code and signature would change per game. Furthermore, there is no standard way to dissassemble the library in IDA or use our automated tools to locate the functions. So with that being said, Cxbx CANNOT emulate these games using the method it uses now. The only way to do so is to actually create an HLE datasheet that manually specifies the location of each function similar to how Xeon works. This is really a lot of work to do since most games require many functions to be HLEd and finding them all manually can take months (unless we had a dedicated team to search them out). Now I see what Nisse was talking about =/

So, that's all I wanted to share tonight. In the mean time, I can still add a few updates here and there. Just know that I'm not completely off of this project for any reason! =)

Shogun.