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Guests: Athomas Goldberg, Jeff Kesselman, Daniel Petersen, and Ken Russell MDR-EdO: Welcome to today's Java Live chat on open source APIs for Java Technology Games. These APIs include Java Binding for OpenGL (JOGL), Java Bindings for OpenAL (JOAL), and JInput. Our guests today are three key members of Sun's Game Technologies group (the group responsible for these APIs): Athomas Goldberg, Jeff Kesselman (Jeff is not here yet), and Daniel Petersen. Also joining us is Ken Russell, who is a coauthor of the JOGL API. Our guests are ready to answer your questions about the APIs, and about Sun's support for Java technology games in general. So let's first level set. Athomas, Jeff, Daniel, and Ken, can you give us a brief overview of these APIs? Athomas Goldberg: OpenAL is a 3D audio API that's rapidly becoming a standard for games and is supported in hardware on audio cards by Creative and others. JOAL gives Java technology developers access to hardware-accelerated 3D audio by providing wrappers to these native APIs. Ken Russell: JOGL is a Java binding for the OpenGL 3D graphics API. It integrates with the AWT and Swing widget sets and provides high-performance, portable access to the latest 3D graphics features supplied by OpenGL and the vendors' graphics hardware. Athomas Goldberg: JInput gives developers the ability to do discovery and polled input of a variety of game controllers Guest: When is JD3D coming? :) Daniel Petersen: With our new friendship with Microsoft who knows? Martin: Does the OpenAL API fit into the JMF or is it an independent API? Athomas Goldberg: It is an independent API, but we are looking at how to integrate JOAL with JMF and Javasound so that developers can use them together in their games. ***: How close is JOAL to being ready for production use? Athomas Goldberg: The APIs are not likely to change. JOAL has been tested and appears to be working fine on most platforms, but still needs further testing. There is a known issue with the nVidia OpenAL drivers, for which we have a work around, and are working on resolving. Dave: Who are these APIs mostly aimed at? Companies, individuals, open source groups? Daniel Petersen: These APIs are open source APIs so they are meant for everyone. Dave: Which graphics card vendors have you been working with to implement JOGL? Ken Russell: The original code was developed independently of any particular graphics card manufacturer, but we've been in talks with at least ATI and NVidia.
pmattos: Are any of these APIs taking advantage of the Ken Russell: JOGL was designed for New I/O. We have several demos on the JOGL-Demos web page that show that you can get the speed of optimized C++ code while still keeping the safety and portability of Java. ***: Will JOAL and JOGL be integrated into Java 3D? It's a lot of effort writing your own scenegraph :( Athomas Goldberg: The next version of Java 3D will most likely be aimed at incorporating certain heavily-requested features. Later, the Java 3D team will be looking at making larger changes to the architecture, at which point JOAL and JOGL will probably come into the discussions, but nothing has been decided at this point as far as I know. Spiff: It would be nice to eventually see something like JOGL in J2SE. Is that seen as a possibility perhaps for 1.6 or is it very unlikely that we'll ever see JOGL in J2SE? Daniel Petersen: JSR-239 has been formed to create Java bindings to OpenGL ES. OpenGL ES is quickly becoming the industry standard 3D graphics API on all mobile devices. We hope to have JSR-239 complete by early next year. ***: Do you have any completed games that are already using the APIs? Poster children? Athomas Goldberg: There are a few games in development. Wurm Online is one worth looking at. ***: But none that are actually completed yet? Are there any plans for Sun to write some example games (not just small demos like the cogs demo)? Athomas Goldberg: The APIs have only been available since last June, so I anticipate it will be some time before we begin to see completed games. That said, we are working with some developers who've done demos for us in the past to create some more substantial demos. Spiff: Does Sun plan to devote resources on continued development of JOGL, or is it now up to the rest of the community? Daniel Petersen: Sun is definitely devoting resources to JOGL. I am the Spec Lead for JSR-231 - Java Bindings for OpenGL. This JSR will be based upon the JOGL bindings on java.net. Martin: How does the JOGL API compare with other existing APIs such as OpenGl for Java and the Java 3D API, performance-wise? Ken Russell: JOGL is comparable in speed to OpenGL for Java but is more up-to-date. In terms of exposing the latest hardware features, it is ahead of Java 3D. Depending on your application, you may get better performance with raw JOGL, or you may be able to get better scalability with Java 3D (which has many multiprocessor features built in). Magnetotron: Realistically, what is the 3D performance like accessing it from Java? For example, could you use these APIs to make a competing 3D engine that performs as well as a current popular game engine? Ken Russell: We've given JavaOne talks during the past two years showing comparable speed between Java and optimized C++. I would strongly recommend you look at the slides for these talks and look at the JOGL demos. Chris Morley: RE: A. Goldberg said "the APIs are not likely to change" ... when you say that, do you mean for the foreseeable how many years of graphics and audio hardware? Athomas Goldberg: What I meant was that there is not any additional work needed to support the current OpenAL APIs. In the event that the underlying OpenAL APIs continue to evolve, we will update the JOAL APIs accordingly. Guest: A question for all the APIs: what platforms are they known to work with? Daniel Petersen: All APIs are available for Windows, Linux and Mac. danmich: Ken, You mentioned integration with Swing and AWT. Are there any performance issues with Swing due to double buffering and/or lightweight component architecture? Ken Russell: There is a performance hit when using the lightweight OpenGL widget (GLJPanel), but it isn't necessary to use this component unless you have overlapping widgets in your UI. GLCanvas integrates fine with many Swing UIs. 34134132: With JOGL, can I get accelerated 3D performance in a window as well as full screen? Ken Russell: Yes. aronelston: Where would we find the JOGL demos? Daniel Petersen: https://JOGL-demos.dev.java.net/ cyber101: Will it be compatible with OS X? Ken Russell: Which API specifically? JOGL definitely works on OS X; I believe that JOAL and JInput are also completely ported. Dave: Which of the APIs we are covering here does Wurm Online take advantage of? Athomas Goldberg: Wurm Online uses JOGL, and they are in the process of incorporating JOAL as well. I don't know if they are using JInput at the moment, or have plans to. Perhaps Jeff can illuminate? Spiff: Any plans for supporting shading languages other than Cg? Ken Russell: We intend to support the ARB-approved languages (i.e., GLSLANG) as soon as there is widespread driver support. coe: I could definitely see JOAL helping Java 3D sound, which is currently very poor. Athomas Goldberg: Given the support for hardware-accelerated 3D audio that JOAL gives you, I anticipate it will be seriously considered in future versions of Java 3D. ***: Are you writing tutorials for any of the APIs? Every time I sit down with JOGL I have to use the post that Gregory Pierce did in the Java gaming forums (I bookmarked it after about the third time!) but I can never seem to find decent JOGL tutorials. People sometimes say "it's just OpenGL" but that's not true, it's subtly different in lots of little ways (or it seems to be!) Ken Russell: A lot of tutorials have been ported by the community, in particular the NeHe tutorials. We'd like to assemble these demos into the JOGL-demos workspace so they're in one place -- time constraints have been the only thing preventing this so far. Martin: Will the JOGL API be capable of interacting with the likes of Sun's Project Looking Glass? For example, sound from further away windows could sound further away? Daniel Petersen: Project Looking Glass will have its own API to support 3D rendering and sound. A user would be free to build an application run by Looking Glass using JOGL. jeffa: Any support planned for Tapwave? I see they are sponsors on the contest (I sent this question once already, but it never showed up... not sure if I'm actually getting through)... Athomas Goldberg: Not at the moment, though I think that's a great idea. ***: Does JInput work with gamepads? I mean, actually tested and working on each of the three platforms? (I don't have one so I couldn't test myself! But we're doing a game where gamepads would be a BIG advantage, and it would be really cool to be able to say "supports gamepads" in our instructions) Jeff Kesselman: JInput has been tested with some gamepads on all 3 platforms and seems to work. Rumble is a new feature and I'm not sure if its been tested on all 3 platforms. ***: Cool about the gamepad. Is there anyone we should talk to at Sun if someone has problems with a gamepad? Jeff Kesselman: Well, these are community developed plug-ins so the community supports them If you run into a problem then you want to ping the community. danmich: Is any of this technology used in Project Looking Glass? Daniel Petersen: Project Looking Glass is currently using Java 3D. jeffa: How far along is each project in terms of usability by developers? Athomas Goldberg: All 3 of these technologies are being used by developers. We are currently cleaning up the APIs and documentation with the intention of releasing a stable 1.0 release in the near future. Spiff: Given the new Relationship, is JOGL on Xbox2 a likely possibility? Athomas Goldberg: We'll see if the folks in Redmond start answering our phone calls :) Martin: Spiff - the Xbox is basically an x86. If you can run the JRE, surely it must be possible to use most of the APIs? Athomas Goldberg: That stands to reason, though in the case of JOGL and JOAL, we are wrapping native libraries, so the native libs would need to run on the Xbox first. Spiff: Likewise, is there some possibility of seeing JOGL on PS3? Athomas Goldberg: Not much I can say here except that we are in the midst of several "executive level" discussions with Sony on a wide range of issues which most certainly include this. falken: How similar will OpenGL-ES be to JOGL? For those that are eagerly awaiting JSR-239, would it be worth learning JOGL in preparation? Ken Russell: Yes, all of the core concepts in OpenGL will certainly apply in OpenGL ES, so learning OpenGL is the right first step. danmich: Nice demos :-) Work even on JDK 1.5 beta. Athomas Goldberg: Thanks :-) ***: Apologies if it's somewhere obvious and I've missed it, but is there a list online of what gamepads HAVE been tested? And, more generally, is there a listed of "known to work" hardware for each of the APIs? Compatibility testing seems to be one of the biggest expenses with development at the moment, so it would be great to have a list of "should work" hardware so that we could say "if your hardware isn't on the list, we shouldn't get too worried if you seem to have weird bugs". Jeff Kesselman: Nope. You can post the question in the JInput topic, though, and the guys who are doing the plug-in development can answer. Jeff Kesselman: JInput relies on the underlying APIs-- DirectInput under Win32, HID Manager under OSX, etc. The platform-specific code is totally contained within plug-ins. Thus you can extend the system by adding arbitrary plug-ins to your distribution. In general though, JInput should support any input device the underlying APIs support. ***: Speaking of contests, how about a special contest with three categories: "Best use of JOGL", "Best use of JOAL", "Best use of JInput" or something like that? Athomas Goldberg: Hmmm... Have to think about that after the current <shameless-plug>Java Technologies Game Development Contest </shameless-plug>. aronelston: Project Looking Glass is very interesting. At what point will developers be able to start working on projects for Looking Glass? Also, will any Java 3D applications built now have full functionality on PLG or limited functionality without access to the OS APIs? Daniel Petersen: While some members of the GTG work with the engineers on Project Looking Glass, we are really not up to speed with their release plans. gameboy: Will I lose any performance in my C++ OpenGL-based games if I convert to JOGL? Ken Russell: It depends on the algorithms and data structures you use. We've demonstrated several medium-to-large Java games and 3D applications at the past few JavaOne conferences that were comparable in speed to the analogous C++ code where it was available. Check out the slides from the past couple of conferences, the JOGL-Demos web page, the JOGL forums on javagaming.org, and the JCanyon demo on java.sun.com. jeffa: Are these APIs fair game for the contest? The rules were kind of fuzzy. They say Java ONLY, but these APIs are calling native code, right? So does that disqualify them? Daniel Petersen: Yes, these APIs can be used in the game contest. What we tried to say in the rules is that any API on java.net and java.sun.com could be used. While the APIs call native code, your game would only call Java methods within these APIs. 34134132: Would JOGL be a good choice for fast 2D graphics in a window? Ken Russell: I think so. You can make textures containing your sprites and move them around by drawing simple polygons. gameboy: What impact do you see the recent Sun-Microsoft agreement having on the future of Java-based game technology? Athomas Goldberg: That remains to be seen. It all depends on what happens when I send in the application for the Xbox middleware developers program... :-) Jeff Kesselman: The agreement does prolong the life of MSVM in the Win32 environment, which is good for web developers. In the long run, it opens the door to the possibility of Microsoft shipping a more advanced (e.g. Sun) VM, though there is nothing solid in place there yet. cyber101: *watching Project Looking Glass video* Wow. I'm impressed! Jeff Kesselman: I'll tell Hideya next time I see him :) Dave: Where are the slides from Java One available from? Ken Russell: http://java.sun.com/javaone/ . Look for TS-2125 in JavaOne 2003 and TS-3167 (I believe) in JavaOne 2002. You need a JavaOne Online login to see the slides. cyber101: What kind of video card would be required to run Project Looking Glass? Daniel Petersen: People have been running the current Project Looking Glass demo on GeForce2 cards. Zorn: As far as I've seen from a user perspective, Java tends to have a bad reputation in gaming. What's being done to increase not just the technical aspects, but also its popularity as a language for programming good games? Jeff Kesselman: That reputation is actually changing pretty rapidly among those in-the-know. A number of major games have shipped that are part- or all-Java that have done very well (e.g. Law and Order, IL2 Sturmovik) We have been showing myth-busting demos at CGDC for about 4 years now. In the long run though, nothing succeeds like success. As more Java technology-based games make big money, more people will feel comfortable using it. ***: Could you comment on the JGF page, and your own plans to make an exciting showcase web site for Java games? That site is trying to generate positive reputation and show off the great games people have "in development". I think it will move to it's own domain soon, but was initially just a list of games that people had posted on javagaming.org. Jeff Kesselman: I haven't seen that particular page, but any and all pages dedicated to showcasing Java Games is Great! We are actively working to highlight games on java.com as well, and you'll see more of that over the coming months. Martin: Wouldn't a commercial release from Sun demonstrate that Sun is willing to use the technology and thus improve its popularity? Athomas Goldberg: Our intentions in making the technologies open source is to give the community as much control over their evolution as possible. That said, we do understand the importance of "supported" technologies to commercial development and are currently working on how best to manage this. Jeff Kesselman: Thats the great thing about community support. If there's something that really needs doing, generally someone finds time to do it :) I should mention that while the Win32 plug-in for JInput came from Sun, both the Linux and OSX were done completely by volunteers. And volunteers have improved our original Win32 plug-in! danmich: Swing in JDK 1.5 uses an experimental Java 2D pipeline with OpenGL. Does it use its own bindings, or there is some common work with JOGL? I must say that in Linux and NVIdia 3, I'm not very impressed with application performance using OpenGL pipeline (2-3 times slower then standard pipeline). Ken Russell: The Java 2D OpenGL-based pipeline uses its own native code to access OpenGL. We've seen dramatic speedups with the OpenGL Java 2D pipeline in many situations; you should send feedback to that team if you're seeing performance issues. Martin: Are there any plans at Sun for commercial release of games on the Java platform? Athomas Goldberg: We have no plans to go into the game publishing business ourselves, but are working closely with a number of commercial developers who are using various Sun technologies in the production of their games. jeffa: Any demos or sample code for JInput? The API looks pretty simple to use and the Javadocs are pretty solid (I'm just now starting to dig into the APIs), but some sample code never hurts... :-) Jeff Kesselman: Yes. There are two demo applications that are part of the JInput source tree. Both are simple, but they show how to use it. (We also use them to test new plug-ins.) JInput Docs are JavaDocs right now and are a bit sketchy. I'm working on more complete docs, but unfortunately its a spare-cycles project. The JInput forums are active and very helpful when you run into questions that aren't well documented yet. Dave: I noticed the K700 phone released by Sony Ericsson the other day - it was listed as supporting Java 3D. Would this actually be OpenGL ES? Daniel Petersen: I am not aware of this phone; however I wonder if they really meant JSR-184 and not Java 3D. JSR-184 is a scene graph API very similar to Java 3D but pared down for mobile devices. Much like Java 3D is built on top of OpenGL, JSR-184 could be built on top of OGL ES. ***: A lot of people are confused about the MSVM situation (including me). Can you explain (or have a URL) *exactly* what MS is allowed and not allowed to do with their VM now? Do they have to put in the things they took out (like RMI - I had colleagues whose games were broken because MSIE didn't have RMI). Ken Russell: As a member of the HotSpot JVM team, I think I can comment on this. There were some legal issues of whether they were "allowed" to continue shipping the MSVM, etc. that I don't know the details of; however, going forward, the MSVM is not going to be supported (or, eventually, even shipped) by Microsoft. We recommend you test your old applets with the new Java Plug-In, which can completely replace the MSVM, and provides higher performance and all of the latest features of the J2SE platform. Many OEMs are shipping Java bundled on their systems -- more than 50% of the new PCs shipped per year. PyroX: Will these games all be interoperable? Meaning all systems that can run Java? Daniel Petersen: Not sure what "these games" are, but in order for a game that uses, say the JOGL API to work, you would need to have the JOGL package on the system - either by a download and install or through Web Start. aronelston: According to the Project Looking Glass FAQ, a SDK for PLG will be released mid-2004. Just answering my own question. :) Daniel Petersen: Even we learn something new here!-) Thanks. Zorn: I heard you were all talking about Wurm Online, which is an awesome display of the power of the language. Jeff Kesselman: Yep. Wurm is a dynamite product. Their are some other really good ones out there too (I really like Kingdoms of War for instance.) They (Wurm) actually lent us their client tech and we used it as the basis of a demo of some new server tech we showed at CGDC and will be showing at JavaOne. falken: Are there plans to add more APIs to the existing 3? (A physics API would be nice). Daniel Petersen: Check out: https://odejava.dev.java.net/. ***: re: JVM's, we would REALLY appreciate some statistics - no matter how vague - on what the current "penetration" of the new JVMs is. The 50% install is great, and has been going for about a year (yes?) but we have no idea what the installed base figures are. When talking to publishers (and especially big ones like EA) it makes a HUGE difference if we have some figures on this Ken Russell: Take a look around the java.sun.com and java.com web sites. I think there is a fair amount of marketing material that may provide these numbers, or at least our best estimates. The download numbers for the JRE have skyrocketed over the past couple of years and I would have to assume that our installed base has grown substantially. kevglass: In what time frame do you see the "core" APIs moving into the core Java? Jeff Kesselman: At the moment, as they are open development and not built to any JCP standard, they really can't. That doesn't mean though that the GTG won't try to get them deployed WITH J2SE wherever we can. In the long run though, to make them part of a standard platform we will have to go through the standards process (the JCP) Spiff: Since there is a member of the HotSpot team present, are there any plans to expose SIMD instructions to Java? Things like dot products are common in games and might be helped by this. Ken Russell: There are no current plans to expose APIs, though we definitely would like the HotSpot compilers to automatically recognize certain kinds of loops and compile them using vectorizing instructions. We currently use scalar SSE/SSE2 instructions in the server compiler on PIII/P4 CPUs; we will expand this to the client compiler in a future release as well as working on both compilers' optimizations. jeffa: What kind of marketing muscle is Sun planning on putting behind their games effort? A Java games site for users based around Web Start would be cool. The key for micro-developers would be someone handling the billing, etc. I'm thinking specifically of something like RealArcade. Athomas Goldberg: At the moment we are working on several avenues to enable game developers to showcase their work. We are putting together a "Beta" games page for Java.com that will spotlight games in progress, and are constantly looking for new games to spotlight on the site. Having the games Web Start-accessible from the site is a great idea. We don't currently have plans to sell games through the site, but I'll bring this up with the Java.com folks and see what they think. ***: re: commercial release...writing games is very expensive! :) Athomas Goldberg: Very true, though as the Law & Order guys discovered, the productivity gains that come from using Java can greatly reduce the time and cost of creating a commercial game. ***: to: Athomas re: sun making profit from games, I've offered before to show the GTG real examples of this in other parts of the games industry, and show them how to get it up and running (the challenge is not technical, it's about positioning, marketing, etc) Athomas Goldberg: I completely agree. There are no technical issues as far as I understand it. It goes deeper into Sun's global relationship to owning, selling and delivering content which extends well beyond games. We can continue to make the case for doing it, but until Sun is prepared to do it across the board (and across industries) it's not likely to happen. Personally, I hope it does happen in some form, but a lot may have to happen first
cyber101: Are there any performance changes between running a game with Java Web Start or running it as an
Ken Russell: I'm not sure what you mean by running it as an cyber101: Well for example, you can run Wurm Online by running it on the web site itself, but Kingdoms of War requires you to download and install the setup. Ken Russell: It looks to me like Kingdoms of War could just as easily provide a Java Web Start launch link. You might want to contact them and ask them about this. gameboy: I've been reading about the game server prototype that Sun demo'd at the Game Developers Conference a few weeks ago. an I get detailed information about it? Also, when will the "real thing" become available? Jeff Kesselman: Ah. Thats my baby so I'll field that. I'm afraid on info the best answer I can give you right now is "Real Soon Now." We have a white paper, it's currently being reviewed by the lawyers. As soon as it's available I'll make sure to post a link on the games community forum. I've actually already posted a fair bit of off the cuff info answering questions there. In terms of "the real thing", currently it's a Technology. How fast it moves from that to a state where it's available to outsiders is really a factor of how much interest we get from outside. We *did* see a lot of interest at CGDC so I'm hoping that moves it along :)
Spiff: 1.4.2
Ken Russell: In the next release of Java, we are going to work on more ergonomic compilation strategies which should eliminate the need to specify kevglass: re: 1.4.2 deployment, does this mean we might have a chance of seeing Cas' modular JVM? Jeff Kesselman: Well first of all we call it a "striped" VM because modular implies things that Cas doesn't mean and aren't technically possible. I don't think you will ever see a bare VM. HOWEVER, the J2ME platform does define smaller VM and library combinations. We tried one with JSR-134 to define a minimal VM and library combo for games. That might happen again. Martin: How well do the APIs discussed work with the Full-Screen Exclusive Mode API? Jeff Kesselman: JInput and JOAL should be fine. Full screen Exclusive is generally used in an "active paint" loop. Both JOAL and JInput are designed for use in such environments. (Thats one of the primary reasons for JInput. Besides discovery, it lets you poll input rather then having asynchronous events.) ***: Do you guys work on the core APIs full-time? Or is it just a hobby? Or...is it like you're allowed X hours per week (e.g. your bosses say "you can spend 3 days a week on JOGL")? Athomas Goldberg: We don't currently have an allotted time set aside for work on these technologies and have had to split our time with other responsibilities. That said, we have recently made some changes in the organization that should ensure that these APIs get the attention they deserve. kevglass: How do you, the game industry, get over the current hurdles put in front of use of Java for games development? (i.e. No trusted trained engineers, misconceptions with Java, lack of infrastructures or tool support)? I realize you guys are working towards this, are there any arguments/techniques you've been using that might help the community to convince the "unconverted"? Ken Russell: The best arguments I can offer are multiple demonstrations showing that there are no major performance discrepancies any more between C/C++ and Java. The Java tools are already excellent and there are some novel tools like back-in-time debuggers that have come out recently that are not feasible to do with C/C++. My advice is to just build great games with Java; that will show the world how it can be done. Martin: RE: Full-Screen Exclusive Mode API - Is there much of a performance benefit to using the FSEM API? Jeff Kesselman: On Windows and Linux it's definitely the fastest way to go for standard (non-JOGL) 2D. On Win32 it means flipped pages. While X can't flip video memory, there are other tricks that help. There is a performance issue on Mac today. Apple knows about it and considers it a bug. Chris Morley: RE: no major performance discrepancies...are there minor ones across the board or just a couple of straggling situations with certain data structures (et al) that are egregious and must be avoided? Ken Russell: Last answer -- but we're generally within 90-100% of C++ speed as shown by previous demonstrations we've done. Generally, the performance of your application nowadays is going to be mostly dependent on your data structures and algorithms rather than whether you've used C/C++ or Java. MDR-EdO: Well we've quickly come to the end of our session. I'd like to thank everyone who logged in today--I thought we had a nice range of questions. And of course, I'd like to thank our guests Athomas, Jeff, Daniel and Ken for their answers. Dave: Thanks a lot guys! 34134132: Yes, thanks for taking the time to do this! Ken Russell: Thanks to everyone for joining us and for a lot of interesting questions. Please look at the gaming forums on javagaming.org, which we frequent. Also look for gaming-related sessions at the upcoming JavaOne 2004 conference. jeffa: Thanks! kevglass: Yep, thanks a lot, could do with this more often :) Jeff Kesselman: Thanks for coming folks. For JInput (or other game related) questions I'd highly recommend stopping by the Java Game Developer community forums. In particular, the discussion forums are very active and very helpful. Martin: Thanks - Very insightful swpalmer: Thanks, I missed most of the chat because of a meeting, but even the last 10 minutes were good. Athomas Goldberg: Thanks Everybody. These were some great questions. Also, there will be a BOF at SIGGRAPH on the Java Game APIs, so if any of you are planning to attend, please keep at eye out for it. Daniel Petersen: Thanks for the questions!
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