Myths 1

The Myths (and Truths) of Java The Myths (and Truths) of Java Games ProgrammingGames Programming

Andrew DavisonAndrew Davison

Dept. of Computer EngineeringDept. of Computer EngineeringPrince of Songkla UniversityPrince of Songkla University

Hat Yai, Songkhla 90112Hat Yai, Songkhla 90112ThailandThailand

ad@fivedots.coe.psu.ac.th

Myths 2

In a NutshellIn a Nutshell

Java for games programming: are you Java for games programming: are you joking? joking?

No, Java is a great games programming No, Java is a great games programming language.language.

Myths 3

The Familiar AdvantagesThe Familiar Advantages

The object-oriented paradigm.The object-oriented paradigm. Cross-platform support.Cross-platform support. Code reuse.Code reuse. Ease of development.Ease of development. Tool availability.Tool availability. Reliability and stability.Reliability and stability.

continued

Myths 4

Good documentation.Good documentation. Support from Sun Microsystems.Support from Sun Microsystems. Low development costs.Low development costs. The ability to use legacy code (e.g. C, C++)The ability to use legacy code (e.g. C, C++) Increased programmer productivity.Increased programmer productivity.

It's It's funfun, especially for games programming., especially for games programming.

Myths 5

Java BashingJava Bashing

1.1. Java is too slow for games programming.Java is too slow for games programming.

2.2. Java has memory leaks.Java has memory leaks.

3.3. Java is too high-level.Java is too high-level.

4.4. Java application installation is a nightmare.Java application installation is a nightmare.

5.5. Java isn't supported on games consoles.Java isn't supported on games consoles.

6.6. No one uses Java to write 'real' games.No one uses Java to write 'real' games.

7.7. Sun Microsystems isn't interested in supporting Java Sun Microsystems isn't interested in supporting Java gaming.gaming.

Almost all of these are substantially wrong. Almost all of these are substantially wrong.

Myths 6

Wake up, it's 2006Wake up, it's 2006

These objections had more These objections had more validity in the late 1990svalidity in the late 1990s– the language and its libraries the language and its libraries

were less sophisticated and were less sophisticated and slowerslower

– lots of hype led to lots of disappointmentlots of hype led to lots of disappointment

Myths 7

1. Java Is Too Slow For 1. Java Is Too Slow For Games ProgrammingGames Programming

Or "Java is slow compared to C and Or "Java is slow compared to C and C++, the dominant languages for C++, the dominant languages for games programming at the moment." games programming at the moment."

JDK 1.0 (1996): 20 to 40 times slower than JDK 1.0 (1996): 20 to 40 times slower than C++C++

J2SE 5: only 1.1 times slowerJ2SE 5: only 1.1 times slower Java SE 6 is about 20% faster than J2SE 5 Java SE 6 is about 20% faster than J2SE 5

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Myths 8

Speed depends on the application Speed depends on the application and coding styleand coding style– Java programmers must be good programmersJava programmers must be good programmers

Jack Shirazi's Java Performance Tuning siteJack Shirazi's Java Performance Tuning site– http://www.javaperformancetuning.com/http://www.javaperformancetuning.com/

Myths 9

The Hotspot CompilerThe Hotspot Compiler

Introduced in J2SE 1.3.Introduced in J2SE 1.3. The run-time system identifies areas of code that The run-time system identifies areas of code that

are utilized many times, and aggressively are utilized many times, and aggressively compiles them. compiles them.

Program execution is often slow at the beginning Program execution is often slow at the beginning until the code has been analyzed and compiled until the code has been analyzed and compiled – splash screens API in Java SE 6splash screens API in Java SE 6

Myths 10

Slow-Moan 1: Swing is SlowSlow-Moan 1: Swing is Slow

Swing GUI components don't use Swing GUI components don't use the OS muchthe OS much– portability, controllabliltyportability, controllablilty– extra layer of processing above OSextra layer of processing above OS

Some games applications use the older, Some games applications use the older, lower-level AWT GUI libraries.lower-level AWT GUI libraries.

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Myths 11

J2SE 5/6 Swing uses OpenGL/DirectX more J2SE 5/6 Swing uses OpenGL/DirectX more directlydirectly

Most games don't require complex GUIsMost games don't require complex GUIs– full-screen game play with mouse and keyboard full-screen game play with mouse and keyboard

controls is the normcontrols is the norm

– mouse and keyboard processing is dealt with by the mouse and keyboard processing is dealt with by the AWTAWT

– full-screen modefull-screen mode

Myths 12

Slow-Moan 2: my Program is Slow Slow-Moan 2: my Program is Slow (because of Java)(because of Java)

Where to lay the blame?Where to lay the blame?– graphics rendering: OpenGL or DirectXgraphics rendering: OpenGL or DirectX– network games: the networknetwork games: the network

Myths 13

2. Java Has Memory Leaks2. Java Has Memory Leaks

Uhh?Uhh?– Java doesn't offer pointer arithmeticJava doesn't offer pointer arithmetic– out-of-bounds array accesses are caughtout-of-bounds array accesses are caught

Myths 14

Possible Meaning 1Possible Meaning 1

Defunct objects are not Defunct objects are not being garbage collected.being garbage collected.

Due to bad programming styleDue to bad programming style– the garbage collector can only do its job when the garbage collector can only do its job when

an object is completely dereferencedan object is completely dereferenced

Myths 15

Possible Meaning 2Possible Meaning 2

Garbage collector is executing at Garbage collector is executing at poorly timed intervals.poorly timed intervals.

The JVM comes with several different The JVM comes with several different garbage collectorsgarbage collectors– can be selected/fine-tuned from the command can be selected/fine-tuned from the command

lineline

Myths 16

Profiling ToolsProfiling Tools

Java SE 6Java SE 6: : jps, jstat, jhat, and jstackjps, jstat, jhat, and jstack

Many third-party toolsMany third-party tools– e.g. JProfiler e.g. JProfiler

Myths 17

3. Java Is Too High-level3. Java Is Too High-level

Abstraction versus speed and controlAbstraction versus speed and control– C++ is too high-levelC++ is too high-level– C is too high-levelC is too high-level– assembler is too high-levelassembler is too high-level– ICs are too high-levelICs are too high-level

– an abacus is sufficientan abacus is sufficientfor all our computingfor all our computingneedsneeds

Myths 18

Historical ObservationHistorical Observation

The gaming community used to think that C The gaming community used to think that C and C++ were too high-level. Until:and C++ were too high-level. Until:– Doom and Dungeon Master, mid 1980sDoom and Dungeon Master, mid 1980s– cross-platform development toolscross-platform development tools

e.g. RenderWare, e.g. RenderWare, GamebryoGamebryo

Myths 19

HighHigh--level Moan 1level Moan 1

Java’s use of classes, objects, Java’s use of classes, objects, and inheritance add too much and inheritance add too much overhead without enough coding benefit.overhead without enough coding benefit.

Class libraries are Class libraries are essentialessential::– high-speed I/O, advanced 2D and 3D graphics, high-speed I/O, advanced 2D and 3D graphics,

networking, etc.networking, etc. Object-oriented design (UML)Object-oriented design (UML)

Myths 20

HighHigh--level Moan 2level Moan 2 Low-level, fast operations -- such as direct Low-level, fast operations -- such as direct

Video RAM I/O -- are impossible.Video RAM I/O -- are impossible.

Full-screen modeFull-screen mode– page flippingpage flipping– control over the screen's resolution and image depthcontrol over the screen's resolution and image depth

Graphics rendering using OpenGL and DirectX.Graphics rendering using OpenGL and DirectX.

Myths 21

HighHigh--level Moan 3level Moan 3

Java can't use game peripheralsJava can't use game peripherals– e.g. joysticks and game padse.g. joysticks and game pads

Yes it can:Yes it can:– JNI, the Java Native InterfaceJNI, the Java Native Interface– JInput, the game devices API JInput, the game devices API

https://jinput.dev.java.net/https://jinput.dev.java.net/

Myths 22

4. Installation Is A Nightmare4. Installation Is A Nightmare

1.1. Java has to be on the machine before the Java has to be on the machine before the application will run.application will run.

2.2. Code bloatCode bloat– even small programs require a 16 MB JREeven small programs require a 16 MB JRE

3.3. Frequently changing JVMs.Frequently changing JVMs.

4.4. Non-standard components are often Non-standard components are often required (e.g. Java 3D).required (e.g. Java 3D).

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Myths 23

5.5. It's not possible to compile the application for a It's not possible to compile the application for a specific platform. specific platform.

6.6. The .jar extension is hijacked by other softwareThe .jar extension is hijacked by other software

7.7. The JRE is slower to start up compared to a The JRE is slower to start up compared to a native compiled application.native compiled application.

Solved with good installation softwareSolved with good installation software– except for 2 and 7except for 2 and 7

Myths 24

Many Installation OptionsMany Installation Options

Applets Applets Java SE 6 plugJava SE 6 plug--inin

– for Internet Explorerfor Internet Explorer Java Web Start Java Web Start ((JWSJWS))

– improved significantly since J2SE 1.4improved significantly since J2SE 1.4.. ThirdThird--party installersparty installers

– ee..gg. . install4jinstall4j

Myths 25

Code BloatCode Bloat

Increasingly irrelevantIncreasingly irrelevant– many games weighing in at over 100 MBmany games weighing in at over 100 MB– many graphics and sound card drivers are larger many graphics and sound card drivers are larger

than 15 MBthan 15 MB

Network speeds are a problem, especially Network speeds are a problem, especially overseasoverseas– broadband usage is growing rapidlybroadband usage is growing rapidly

Myths 26

OthersOthers

Sun Microsystems estimates that around 70% Sun Microsystems estimates that around 70% of all new PC's come with a JRE of all new PC's come with a JRE pre-installed.pre-installed.

Slow start-up time, butSlow start-up time, but– better in Java SE 6better in Java SE 6– fairly negligible compared to the total running timefairly negligible compared to the total running time– Java SE 6's splash screen APIJava SE 6's splash screen API

Myths 27

5. Java Isn't Supported On Games 5. Java Isn't Supported On Games ConsolesConsoles

This criticism has some justification. This criticism has some justification.

Two important games platforms: Two important games platforms: – the PS2 and Windowsthe PS2 and Windows– Java isn't available on the PS2Java isn't available on the PS2

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Myths 28

Actually it is possible to run Java on the PS2 Actually it is possible to run Java on the PS2 using Sony's version of Linux, but:using Sony's version of Linux, but:– the OS requires the PS2 to have a hard diskthe OS requires the PS2 to have a hard disk– only limited access to hardwareonly limited access to hardware

Two trends that may help Java: Two trends that may help Java: – consoles are mutating into home media devicesconsoles are mutating into home media devices– the rise of online gamingthe rise of online gaming

Myths 29

Java on the PS3?Java on the PS3?

Basic/premium PS3 versions will have Basic/premium PS3 versions will have – 512 MB of RAM, a large hard drive,512 MB of RAM, a large hard drive,

Linux support, OpenGL Linux support, OpenGL

Casual games programming on the PS3Casual games programming on the PS3– development kits in Spring 2007development kits in Spring 2007– support for an object-oriented languagesupport for an object-oriented language

probably C++/Cprobably C++/C

– virtual machine utilizes JIT technologyvirtual machine utilizes JIT technology

Probably Not

Myths 30

BluBlu--ray Drivesray Drives

Support a version of Java called BD-J for:Support a version of Java called BD-J for:– interactive menus, GUIs interactive menus, GUIs – networking applicationsnetworking applications

Myths 31

Other MarketsOther Markets The PC market is far from minisculeThe PC market is far from miniscule

– US$ 953 million by the end of 2008US$ 953 million by the end of 2008

– over a billion in 2009 over a billion in 2009

Games on PCsGames on PCs– superior, modern hardwaresuperior, modern hardware

video cards, RAM, internet connectionsvideo cards, RAM, internet connections

– more exciting game playmore exciting game play

– many more PC games, particularly in the area of many more PC games, particularly in the area of multiplayer online gamesmultiplayer online games

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Myths 32

Mobile gamingMobile gaming– sales rising to US$ 2.5 billion in 2007sales rising to US$ 2.5 billion in 2007– thought to be around 250 million Java-enabled thought to be around 250 million Java-enabled

phonesphones– Java MEJava ME

Myths 33

6. No One Uses Java To Write Real 6. No One Uses Java To Write Real GamesGames

The number of commercial Java games is The number of commercial Java games is small, but growingsmall, but growing– won awards and bestsellerswon awards and bestsellers – e.g. Tribal Trouble, Puzzle Pirates, Call of e.g. Tribal Trouble, Puzzle Pirates, Call of

Juarez, Chrome, Titan Attacks, Star Wars Juarez, Chrome, Titan Attacks, Star Wars Galaxies, Runescape, Alien Flux, Kingdom of Galaxies, Runescape, Alien Flux, Kingdom of Wars, Law and Order II, Ultratron, Roboforge, Wars, Law and Order II, Ultratron, Roboforge, IL-2 Sturmovik, Galactic Village, Wurm IL-2 Sturmovik, Galactic Village, Wurm Online, ...Online, ...

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Myths 38

Java is used widely in the casual gaming marketJava is used widely in the casual gaming market– game play is more innovative game play is more innovative – implementation timelines are shorterimplementation timelines are shorter– budgets smallerbudgets smaller– less man-power neededless man-power needed

By 2008, the casual games market will surpass By 2008, the casual games market will surpass US$2 billion in the US.US$2 billion in the US.

Casual Gaming MarketCasual Gaming Market

Myths 39

Many Java Gaming SitesMany Java Gaming Sites

Sun Microsystems showcaseSun Microsystems showcase– http://www.java.com/en/games/http://www.java.com/en/games/

Community pagesCommunity pages– http://community.java.net/games/http://community.java.net/games/

Open-source gaming toolsOpen-source gaming tools– https://games.dev.java.net/https://games.dev.java.net/

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Myths 40

The Java Games factoryThe Java Games factory– http://javagamesfactory.org/http://javagamesfactory.org/

Works-in-progressWorks-in-progress– https://games-forge.dev.java.net/https://games-forge.dev.java.net/

JavaGaming forumsJavaGaming forums– http://www.javagaming.org/http://www.javagaming.org/

Myths 41

JavaGaming.orgJavaGaming.org

Best source of Best source of technical advicetechnical advice– over 9000 highly opinionated registered users over 9000 highly opinionated registered users

Discussion topicsDiscussion topics– Java 3D, Java 2D, Java Sound, J2ME, networking, Java 3D, Java 2D, Java Sound, J2ME, networking,

online games development, performance tuning, online games development, performance tuning, JOGL, JOAL, JInput, and more JOGL, JOAL, JInput, and more

Myths 42

OpenOpen--source Gaming Toolssource Gaming Tools

JOGL, a Java binding for OpenGLJOGL, a Java binding for OpenGL JOAL, a binding for OpenAL (a 3D audio JOAL, a binding for OpenAL (a 3D audio

library)library) JInput, a game devices API JInput, a game devices API games-middleware and games-forge games-middleware and games-forge

sections sections

https://games.dev.java.net/https://games.dev.java.net/

Myths 43

BooksBooks

continued

Myths 44

http://fivedots.coe.psu.ac.th/~ad/jg

due out in May 2007

Myths 45

7. Sun Isn't Interested7. Sun Isn't Interested

J2SE 1.3 J2SE 1.3 – improved graphics and audio capabilitiesimproved graphics and audio capabilities

Version 1.4 Version 1.4 – full-screen mode and page flipping in hardwarefull-screen mode and page flipping in hardware– faster I/O, memory mappingfaster I/O, memory mapping– support for non-block socketssupport for non-block sockets

useful in client/server multiplayer gamesuseful in client/server multiplayer games

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Myths 46

Version 5.0Version 5.0– nanosecond timernanosecond timer

Java extension libraries, e.g.Java extension libraries, e.g.– Java 3DJava 3D– JMF (the Java Media FrameworkJMF (the Java Media Framework))– the Java Communications APIthe Java Communications API– JAXP JAXP ((Java’s peerJava’s peer--toto--peer APIpeer API))

continued

Myths 47

Java SE 6Java SE 6– improved graphics rendering speedsimproved graphics rendering speeds– splash screen API, scripting, desktop APIsplash screen API, scripting, desktop API

Sun-sponsored websitesSun-sponsored websites– httphttp://://wwwwww..javagamingjavagaming..orgorg– httphttp://://wwwwww..javajava..netnet– httphttp://://communitycommunity..javajava..netnet//gamesgames//

Myths 48

Sun's Project DarkStarSun's Project DarkStar

Tools for supporting massive multiTools for supporting massive multi--player player online games.online games.– server sideserver side: : Sun Game Server Sun Game Server ((SGSSGS))– client APIs for Cclient APIs for C++++, ,

Java SE, and Java MEJava SE, and Java ME

http://games-darkstar.dev.java.net

Myths 49

8. In a Nutshell8. In a Nutshell

Java for games programming: are you Java for games programming: are you joking? joking?

No, Java is a No, Java is a greatgreat games programming games programming language.language.