Taking Tiger Woods Java Golf OnlineTaking Tiger Woods Java Golf Online

Phil Sorger

Robert Burnett

GAMEDevelopers Conference 2000

What We’ll CoverWhat We’ll Cover

EA San DiegoJava Perceptions and RealitiesCyberViewerPGA TOUR Golf OnlinePorting C++ to Java

It takes an InternetIt takes an Internet… the new platform!… the new platform!

It takes an InternetIt takes an Internet… the new platform!… the new platform!

• Old Audience – GamersQuake, Wing Commander, Command & Conquer, Ultima, Madden Football, MS Flight Simulator

• New Audience – EveryoneBass Fishing, Barbie, Bargain Product, Millionaire

• The BrowserExplorer 3, 4, 5Netscape 3, 4, 5AOL 4, 5

• The LanguageJava – SunJava - Microsoft

It takes an InternetIt takes an Internet… the new platform!… the new platform!

• The client machinewide variety of architectures

- Macintosh- PC- Unix ...

200 to 1000 megahertzvideo accelerationconnection speed

- AOL users - 28.8 (56k connected at 14.4)- Cable, DSL - heavy users, influencers

• Our Audience "Golf Fans“Men and WomenMultiplayer, chat orientedlots of disposable income, well educated

Java as a PlatformJava as a Platform

PerceptionsSurprises ProblemsRealitiesPortingRecommendations & Alternatives

Java PerceptionsJava Perceptions

Multi-platform – PC, Mac, Unix … Portable Easy to Code and Port from C++ Secure Supported Efficient

Java SurprisesJava Surprises

Builds even a big project *very* fast Easy to publish patches Generates reasonably small code Hard to crash a machine, leak memory or

scribble on the screen Hugely scaleable Language very flexible

Java ProblemsJava Problems

Slow execution speedNo hardware access (acceleration)

– 2D/3D video, audio, inputLimited Multimedia APIsBuilt-in support stops at 1.1.xMemory Management and Garbage

Collection

Java – Perceptions vs. RealityJava – Perceptions vs. Reality

Multi-platform not even Multi-Browser Portable VJ++ vs VisualCafe vs Sun Easy to port from C++ No enum

no primitive pointersno implicit constructionno right click

Secure Code validation causes slow startup

Supported Microsoft vs Sun Efficient The Internet Sucks

The ChallengeThe Challenge

Objective: allow users to follow (view) golfers in official EA Golf tournaments.

Maximize audience Browser based

Simplify development 100% Pure Java

The Solution - CyberViewerThe Solution - CyberViewer

Showcase EA SPORTSTiger Woods 99PGA TOUR Golf

Anyone with the retail game can compete

Multi-roundprofessional format

Cash prizes“$65,000 purse”

Archive winning performances

CyberViewer ComponentsCyberViewer Components

ShotHunter and ShotServer ServersJava Shotlist Replay Engine Website (previous screen)

ShotHunter and ShotServerShotHunter and ShotServer

Responsible for creating shot assetsHunter waits for new shotsServer replays shot and posts:

– Tee and Snap background jpegs– ReplayBuffer– Z Buffer– Shotlists

Java Engine ComponentsJava Engine Components

DASH Library/API– Display Animation Sprite Handler

Ported EA Code– Golf specific classes and routines

Main Game Control– User Interface

DASH and DARTDASH and DART

DART Animation Editor– DASH Animation Render Tool

Double-buffered Display– built-in Restore(), Blit() and Flip()

Generic Handlers– File I/O, Audio, Security, Version

Management, Animation, Debugging, Network I/O, 3D Cameras, etc.

Ported EA CodePorted EA Code

GolferGolfBall and GOLF_BALL_STATETGame, TPlayer, and ShotOverhead, Scoreboard, LiemeterReplay and ReplayBufferZBuffer, Camera and TGolfView

Sneak Preview Sneak Preview PGA TOUR OnlinePGA TOUR Online

Fully interactive Multi-player Golfers Courses Physics Web / Chat

Porting C++ to JavaPorting C++ to Java

I. Array of Objects or References?

II. Stack Object or just a Reference?

… watch out for “=“

III. The stdio and WINAPI Class

IV. Callbacks

V. Globals

Array of Objects or References?Array of Objects or References?

class BrainCell extends Point { }

class Brain {

public static final int kBrainCells = 100;

private BrainCell[] brainCells;

public Brain(){

brainCells = new BrainCell[kBrainCells];

brainCells[0].x = 0; // !NULL POINTER EXCEPTION!

brainCells[0] = new BrainCell();

brainCells[0].x = 0; // now it’s ok!

boolean[] bInUse = new boolean[kBrainCells];

bInUse[0] = true; // OK, primitive type!

}

Stack Object or just a Reference?Stack Object or just a Reference?

Point WorldToScreen(Vector3 ballV)

{

Point screenPt; //! Just makes a pointer (ref)

Vector3 v; //! same thing, just a pointer!

v.x = ballV.x; //!NULL POINTER!

v = new Vector3();

v.x = ballV.x // now it’s ok!

v = ballV; // not a Copy constructor!

// what happened to old v.x???

}

The stdio classThe stdio class

public static char[] strcpy(char[] dest, char[] src){

System.arraycopy(src, 0, dest, 0, src.length);

return dest;

}

public static String strcpy(char[] dest, String src){

src.getChars(0, src.length(), dest, 0);

return src;

}

public static String strcpy(String dest, char[] src){

dest = new String(src);

return dest;

}

//etc, etc, etc…

The WINAPI classThe WINAPI class

public static long time() {

return new Date().getTime();

}

public static MSG PeekMessage(int wRemoveMsg) {

if(messageQ.size()==0) return null;

MSG lpMsg = (MSG)messageQ.firstElement();

if(wRemoveMsg==PM_REMOVE)

messageQ.removeElement(lpMsg);

return lpMsg;

}

// etc, etc, etc...

CallbacksCallbacks

interface AcceptorCallback {

public void OnAccept(Socket s);

}

class CSock extends Socket implements AcceptorCallback{

void OnAccept (Socket s) { }

}

CSock cs = new CSock();

ServerSocket ss = new ServerSocket();

Socket acceptSocket = ss.accept();

((AcceptorCallback)cs).OnAccept(acceptSocket);

GlobalsGlobals

class Game

{

public static int gNumPlayers; // global

public static final int MAX_PLAYERS=4; // const

public static void PrintNumPlayers() { // method

System.out.println(“players=“ + gNumPlayers);

}

}

if(Game.gNumPlayers <= Game.MAX_PLAYERS)

Game.PrintNumPlayers();

// ALL GLOBALS BELONG IN THEIR OBJECT’S CLASS!!

RecommendationsRecommendations

Design the experience appropriately Limit real-time requirements Maintain focus on main applet Port standard C++ routines

– strcpy, memcpy, WININET, Peek/PostMessage, rand, fopen

Consider “dirty” Java– Blend pure and DirectX

Alternatives & ConsiderationsAlternatives & Considerations

ActiveX Execution Speed

Netscape Plug-In Support

Flash vs. Ease of development

C++ Application Size Requirements

Java Script “Time to Play”

HTML / ASP Asset conversion

Design IssuesDesign Issues

Pacing of the experience- Keep the user occupied

readingplayingwatchingchatting

- Keep the user informed load timeswalk away time (advertising)

Design IssuesDesign Issues Single or Multiplayer

Manage wait - Turn based multi-player can get very slow

Group players based on …experienceinterestperformanceregion

Audience

Simplicity of operation

Information on JavaInformation on Java

Presentation materials available at www.easandiego.com

CyberViewer at tiger99.easports.net/viewer

Java information from Sun java.sun.com

Sun - JavaOne Moscone Center, SF. June 6-9, 2000.

Java programming tech shops developer.com

QuestionsQuestions