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Quake2 Engine In Java
An anonymous reader writes "Ok, so the game is old and there was a really poor web version some years back, but some guys at Bytonic Software in Germany have done a full source port of the Quake2 engine from C to Java. It's cross platform, performs just about as fast as C and has room for further improvements according to the developer. Also, there was another game engine that ran Q3 maps that was shown recently at JavaOne. Are first generation Java games that far behind?"
Maybe this will lay waste to claims that java is slow, bloated, and sucks.
I've only recently started doing heaving Java programming, and I have to say that the language is a dream to code with (provided you use a decent IDE). There're so many classes in place already, there's nothing you can't do. I'll take it over C++ any day, and MS's MFC is horrible on comparison.
My only problem with it is the deployment; screwing with class paths and what not.
People need to realize that most of the overhead they experience with their "hello world" experience has to do with loading the classes in the beginning. Once that is done, Java performs nicely.
Sure, straight C is faster, but Java isn't the turtle everyone makes it out to be.
First released notice in May.
:-)
This is a good demo of the power of Java, it handles the game, then passes this smoothly to the native opengl rendering. Jogl is great, I hope I can find time to work with it some more.
Those crazy Germans do deserve some awesome credit for this! (having lived in Germany I can say I love Germans, and they are crazy!
Sourceforge page
#hostfile 0.0.0.0 primidi.com 0.0.0.0 www.primidi.com 0.0.0.0 radio.weblogs.com
Now you can have the eye candy of Quake 2 with the speed of Doom 3!
I don't care if it's running in Java C D E or bloody Z, as long as the game runs well and looks playable (AKA not shooting green blocks to make red blocks appear with a black block and various brownish walls. ).
No gamers is going to go "Doom 3 running on Java!? I'm so not buying that!" or "Doom 3 is running only on C++ I'm not playing that!". No one but the coders themselvs and the modders will truely care what it's written in as long as it runs okay and looks good.
So gonna get modded Troll..
I like muppets.
but what about when Quake2 came out? The code runs at about 60% performance on today's machines. So when Quake2 was released, Quake2 Java would have broken my machine, as it barely ran the orignal Quake2 version. Java can offer portability over platforms but games often push hardware to its limits and so may raise the bar on minimum system specs.
The important thing to know is that the majority of your performance gains are obtained by scheduling the hardware intelligently, keeping the CPU and GPU well balanced, i.e. busy at all times. And of course, that your tight loops are really optimized, that you do not fragment memory, etc. That, for the most part, has nothing to do with the language your using, but simply with your programming skills.
By the way, what hardware have they tested on to claim that performance is similar? If it's modern hardware, then of course it will run at 60+ fps no matter what.
What's more, I would guess the bulk of the work on the CPU for quake2 consisted in traversing the BSP tree, building the scene (with transforms still being performed on the CPU at that time) and collision detection. The rest is taken care by the graphics hardware so that's totally independant of the language you've used.
There is one thing that bothers me with Java though. You never know when the garbage collection will be performed. Sure, recent virtual machines make it possible to perform garbage collection in smaller but more frequent iterations so you don't halt the system for a few seconds like early virtual machines would do. But still, if you're in a tight loop with your data and instruction cache perfectly populated, and all of a sudden the garbage collection kicks in, then your cache is toast and data will have to be refetched to it when execution resumes. That would result in a horrible performance loss provided you are already really close to the machine's limit. Also, what I'm saying is only pertinent on a console with no (or almost no) OS, because on any PC operating system, your process can be interrupted at any time by the various system tasks that are running, so the garbage collection interrupting your tight loop would only be one of many possible interruptions.
I don't believe java can be as fast as native code, although probably extremely close. And sure, a good java compiler will generate faster code then a crappy C++ compiler.
Another thing I don't like about java is that you have no control over memory (not that i know of, maybe some recent VM extensions allow you to have some control over that?). I really like to be able to give different sets of alloc/dealloc routines to the different subsystems in a game. A subsystem that is known to perform very small allocations/deallocations very often could be passed alloc/free routines that are customized to its use so that memory fragmentation is kept to a minimum. If such a component was allowed to get memory from the same pool then your other subsystems, it would wreck havoc on your memory.
Anyway, it's not such a good idea to compare java and C++ (or whatever other languages) on a system where resources are abundant (PCs).
By the way, Jak & Daxter for the ps2 is written in a lisp derived language (GOAL), yet that game outperforms and looks better then almost everything else on the ps2. Yet lisp is not perceived as a high performance language. But the people at Naughty Dog have developed their very own compiler that is extremely specific to their needs (see their gamasutra post-mortem, very cool read) So, it goes to show that the notion of performance shouldn't be tied with a language, but rather with that language's runtime & compilers.
Ok enough ranting!
Now I haven't used java since 2000, but have they fixed the seemingly random garbage collection? I remember seeing a raytraced wolfy3d java demo years back, and garbage collection would make it go to a stand still at random intervals.
when Push Comes to Shove
No, that is Logo.
Lasers Controlled Games!
A brief snippit from the developer site:
By "ported to Managed C++" you really mean "compiled to IL to run on the CLR". There's a big difference. This code is not managed, its just unsafe code running in a VM (there was more information on this on Channel 9 last week). The radar program they created was written in managed code.
The summary says "Runs almost as fast as the original code!"
The article says "Runs somewhere between 60 and 85% of the speed of the original", and this is on modern hardware.
Let's see how it performs on hardware that was actually used to play Quake 2 before we start lying about how fast java is compared to the native code. When the hardware in question is capable of pulling 300 frames per second, it's pretty damn likely it's not even being used to its full potential. Even the K6-2 machine was getting near 60fps. The only people who got 60fps in Quake 2 when it came out were the people with monster machines.
Sorta. There are numerous games out already that are based on Java. Pretty much all of Popcap uses Java. Java is also used as a scripting language for several games (sorry, no links), as an alternative to Python, Lisp, C++, Lua or any other interpretive language (or home-brewed language).
However, it will be a very long time (if ever) before developers switch over to Java as their language of choice. Why? Because it is only the last generation or two of games that have started to use C++.
Game developers are constantly trying to push the edges of what can be done within current hardware limitations. The problem with languages that do a lot for us is that... They do a lot for us. Which is nice a lot of times. But always seems to happen at the most inconvenient time (like when we're doing matrix operations, or animating units).
I currently have no clever signature witicism to add here.
I happen to know of at least one AAA game which used Java - it used it as a scripting engine.
Nihilistic's Vampire: the Masquerade - Redemption, back in 2000. As I recall, in the Gamasutra postmortem, they commented on how well it worked out for them.
Sadly, I don't know what JVM they were using - but they did say in the postmortem that they didn't write it themselves.
those are the native implementations of jogl and joal (java opengl and java openal). you have to have native c interfaces with the system libraries to achieve these sorts of things.
- tristan
Tr3B (Robert Beckebans IIRC) has written a Q2 clone
in Python some time ago, and currently hacks on
qrazor-fx aka http://xreal.sf.net/ which is a Q2
with graphics quality in the range of Q3 or even
Doom 3.
My Karma isn't excellent, damn it! (And
And I'm a grown up, so I can *decide* if I want to use pointers, gotos, or multiple inhieritance. If you don't like these features in C++ THEN DONT USE THEM.
We may be all grown-ups, but its a sad fact of IT development that we all make mistakes, and pointers aren't an optional extra in C++, they are fundamental to the way data is stored. The use of C/C++ has been a disaster in many areas of IT, leading to buffer overruns, buggy software and virus susceptibility. (I remember spending days trying to trace a buffer overrun in a C++ program on DOS).
Unless you are writing OS kernels, device drivers or hardware controllers its hard to see why anyone would feel the need to use raw memory pointers in an application.
The first commercial Java game was Tom Clancy's Politika, published in 1997. This was followed by Tom Clancy's Ruthless.com in 1998, and Shadow Watch in 1999. I'm not exactly sure what the comment above means, but personally I consider those games first generation. They were burnt onto CD and sold in stores like many a C or C++ title.
Whereas some C/C++ games have used Java as a scripting language, the approach of these games was to use Java for the core game loop and game logic, and to write new native libraries for the performance heavy stuff like graphics and sound. For Politika, we wrote our own movie and sound code (for both PC and Mac) because Java didn't have very good support at that point. We almost got some faster and leaner 2D graphics support in there too, but ran out of time. This approach was written up for a paper (Writing Java Games: How We Did It), which was presented at CGDC 1998.
In Ruthless.com, the native libraries were improved and the 2D graphics support was added. Basically a wrapper was created around DirectX using JNI. In addition, the whole game was compiled to native code instead of using the Java VM. This whole system hit its peak with Shadow Watch, which is an awesome little turn-based strategy game; think Rainbow Six Tactics.
So this has been possible for many years -- it's just that nobody's carried it on. The big accomplishment here is that they may be using only Sun libraries, which only means that Sun has finally gotten their act together and put out well-optimized code.