Game Design, Programming and running a one-man games business…

Category: programming

Maxxing out the PC

When you are running a new PC game, what percentage of your PC is actually working to produce the experience?

Obviously it depends massively on the game, the specs of your PC, your monitor resolution and other factors, but even in extreme cases I suspect it is pitifully small.

The most obvious under utilisation is the CPU. Most games still run in 1 thread, maybe 2 or 3 if there is some sound streaming, possibly more if they are ambitiously attempting multithreaded streaming in of textured data, and maybe a few more for online play. I don’t think that there are many games that will happily place 8 different threads on the 8 cores of my machine (quad core, but hyperthreaded, so showing up as 8). I can max out the CPU by rendering in a 3d package, or by compiling in visual studio, but I’ve yet to see a game manage it. I can understand why, mutlithreaded code is a bitch.

(One problem is, we don’t have exclusive access to all those cores anyway. Right now, this laptop has 53 processes running 715 threads. There are 17,000 handles open (mostly files, one assumes). All I’m doing is typing in firefox)

The second missed opportunity is hard disk access. Go to windows task manager, performance, then check out the resource monitor. Check out all that disk access. Who is doing that? and what for? You can bet that even during a gaming session, a dozen other apps and ‘services’ will be spamming your disk drive.

Of course the same goes for memory, and access to peripherals, the network yada yada.

It makes you wonder just how jaw droppingly awesome a PC game could be if it didn’t have all that nonsense going on all the time. Imagine a special ‘gamer’ mode of windows 8/9 that effectively locked out all those other services, clawed back all the RAM and the cpu cycles, and let your game have console style complete control.

A pipe dream, of course, because of backwards compatibility and a million other reasons, but I do find myself wondering what percentage of my PC is actually needed to play Battlefield:Bad Company 2.  Is it 5%? 7%? certainly not much more?

Ho! Ho! Doh!

There was a bug in Gratuitous Space Battles: Galactic Conquest until today. It was a bit obscure, and very baffling. Basically, in seemingly random circumstances, regardless of file version, people would develop a bug where the campaign backdrop was just plain white. I could not reproduce this. Re-installing seemed to fix it, for *some* people.

Anyway, someone noticed when I asked about it, that a line in campaign.txt storing the background texture name was missing. They had the latest version, and I KNEW that line was in there. It made no sense. Then they noticed that they could paste that line in, when the game was running, and voila, it worked. How weird.

So I looked at my code, and sure enough found some code which overwrites campaign.txt. Old, boring, unused, debug code for doing the campaign editing from about three months ago. This was before that file had this line in it, so because that code had never been updated, it meant that whenever it ran, and  saved out campaign.txt, it overwrote it with a new copy that had no data for the background texture (it used to be hard coded).

What a dork.

But even worse, I had left in this debug code mapped to the ‘H’ key (S was in use), and never remembered to remove it. So if anyone ever pressed ‘H’ during the campaign, it ran.

What a huge dork.

Anyway, it’s gone now. The bad news is, I am obviously a clueless muppet who could not code his way out of a paper bag. The good news is, I fixed this on Christmas Eve. Hurrah! It’s in patch 1.54, you will get it today / tomorrow.

Happy Christmas / Holidays / Festivus / Ascension of Kahless day to everbody!

Quick bug / code update

version 1.51 is live. This does the following:

version 1.51
1) [campaign] Fixed exploit where you get 1 crew when you scrap a fighter.
2) Added new order 'Last Stand' which overrides the auto-behavior of ships retreating if all of their weapons are destroyed.
3) [campaign] Some difficulty balance changes.

it MAY be causing a bit of a crash. I just spotted it, when looking into something else (typical). I’m working on a  quick 1.52 now. It should only happen if you capture enemy fighters, i think, and it s a popup message you can click ignore to, anyway. Ironically, it’s a pop-up message helping me find a rare bug, that I still can’t find :(

Anyway… I have fixed a bug where fleets dissapear on retreating if you viewed the post-battle stats. that will be in 1.52 as well. Plus, I’m working RIGHT NOW on a fix for a retreat related crash bug. I think it’s caused by retreating with a fleet where there is a friendly planet to retreat to, but your ships cannot move there due to anomalies. It should be fixed in 1.52 as well.

The sheer tonnage of code in GSB is staggering.

I hope I get this bug squashed before the apprentice is on :D BAGGS THE BRAND!

Programming tips (and some general tips)

I’ve been in debugging hell for a few days. I’ve had a few nightmare bugs, and learned a few things, as well as having my indie ass saved by some lucky stuff. here is the summary:

I had a bug that was a critical, game-ruining crash thing. When I debugged it, I found the exact line of code that was causing it. I had removed a certain if() statement. I remember doing it about two weeks ago. Can I remember why? Can I hell. IF I had proper comments in the code where I changed stuff, I would have worked out what was going on. IF I had forced myself to check in more regularly and ALWAYS type detailed comments into the check-in softwares submission dialog, I would have worked out what was going on.

Luckily, it wasn’t a disaster, because a long time ago, I clearly made a decision to include my ‘design log’ in the checked-in source-controlled files. This is a long rambling document where I always type everything I’m doing, and have my list of motivating ‘**DONE**’ statements for each day. Naturally, when I made that code change roughly two weks ago, I had written about the problem that needed me to do so. Normally, finding this comment would be a pain, because there are no date stamps on the log, and I wasn’t sure what I was looking for. Hurrah! the design log also has a changelist, and I found the bit I wanted just by seeing the changes made to it in the same check-in as the code change itself.

Lesson: Keep a log of your work, and source-control it. Adding better comments to code doesn’t hurt either.

I had a virus attack on my PC. I think it was some sneaky sleeper-thing that only triggered on a reboot, and I don’t reboot often, so I’m not sure where I got it. It could well be a warez site, which I still check now and then to get some pirated links removed. This virus was pretty nasty. Not only did it breeze past malwarebytes and spybot without triggering either of them (let alone windows defender and the firewall, and the browser settings), but it didn’t announce itself at all. What it did, was trawl through every file on every drive, and with html files, it appended some javascript to the bottom of each file which dropped an exe on peoples machines who ran it. Scary as hell.

I only noticed it because I was editing my website local copies, and spotted in windows explorer that the filesizes of some basic html files were too big. Thank kahless I spotted this before uploading them. The difficult part was then removing them. I noticed that even after running multiple virus scans, and my PC looking clean, if I created a new html file and left it for five minutes, the javascript would be added. There was no dodgy process running, it must have been a rootkit or service.

Anyway… Microsoft Security Essentials is apparently ‘teh awesome’ because it not only killed the virus, it restored every one of my files to their original state without problems. And it’s free. How awesome is that?

One thing I did do, as a precaution after all this (apart from keep MSE installed and running several deep scans overnight with 3 different scanners) is to create a truecrypt container and stick a copy of my website inside it. There is no chance of some virus cracking that open and ruining those files (although in theory it could delete the container). I also keep backups of vital stuff on a thumb drive, just in case. Scary stuff though. Especially because I’m not exactly some dork who accepts .exe files on IRC or opens random email attachments. This stuff is getting harder and harder to avoid.

Where does the memory go?

I haven’t been working on memory optimisations in GSB for a few days, in fact I’ve done nothing but work on features and bug fixes and other stuff for the campaign game. The game is getting better, and looks nicer now, but there is tons to do, a whole host of niggling little things, and some vital balancing and optimising still to do.

But as I work, I keep thinking back to my attempts to optimise the memory footprint of GSB. I wrote an overriden new and delete, to track all my memory (I never use malloc or free). I have spreadsheets showing all the allocations. However, it seems that the memory I allocate is just a trivial percentage of the RAM the game seems to use if you look at it with windows task manager or the windows performance monitor. Of course, there are about 36 different measurements of memory, such as ‘private bytes’ and ‘peak working set’, And nowhere is there a definitive answer on which one to use. However, even using the lowest one, there is still at least 50% of memory unaccounted for. At one point, I checked my stats were not reporting MB as KB, it was that bad.

Sadly, it’s hard to optimise when you can’t see the wastage. I suspect a big chunk of it is particles, but the maths don’t support that. It could be directx making system memory copies of video texture buffers and sound files, but would that be inside the GSB.exe memory footprint? Who knows!

In other news

1) The ecofan really works. In fact it is awesome.

2) Chopping wood from 3 year seasoned timber is trivial next to 10 month felled holly, which is like cutting neutronium with a spork.

3) The UK has a major apple glut. We have some apple trees in the garden and so many apples we literallty can’t walk in the garden for the fallen ones. I actually knocked on neighbours doors to hand them carrier bags full of apples today, just to get rid of a few hundred. It’s insane. We are eating as many as we can, and making apple cakes galore.