Google I/O 2009 - Writing Real-Time Games for Android

[jellyfaceification]

So all of these oop principles gonna slow you down... great

[penna420]

wtf happened to the sound? yesterday it was fine =/

[zzgarbu]

nice sound ;)

[thomasmaagaard]

jkvjku,b, what are you saying, i know it is something awsome, i just don't understand it

[unruheGER]

watched this awesome talk at least ten times in the last couple of months. game programming is pain!

[bboysil]

Check out one of my first 3D application I wrote on my channel or use this: /watch?v=DLplItqq9YA

Tell me what you think. Thanks :)

[burraak1]

Who wants to be a gay for host?

[Speedomon]

00:00:46 you know that you audience consists of a bunch of nerds if they laugh about THAT joke (if it was even meant to be a joke).

wait a second, I probably would too...

[ncr100]

* Use a game-object graph to group all your players, explosions, everything. Objects can hold other objects. The game-loop essentially walks the object graph and calls .execute() on each object, time permitting. If not enough time in the current frame, then some object-groups are skipped. See his "ReplicaIsland" opensource game for example.

[ncr100]

@ncr100 * Each object can do a list of functions, optionally: render, intersect, collect input, etc.

* Use 3 threads: 1. main thread for miscellaneous bootstrapping, mostly idle. 2. game logic thread for updating positions, intersections, etc. 3. rendering thread for blitting.

* Use DDMS to discover unexpected memory allocations by the Java runtime - in places where you think there are no allocations, sometimes there are. Force trigger GC during idle times...etc.

[ncr100]

@ncr100 * Add a profiler to collect stats from the start of your project. Dump values to the log every 3 seconds. Not to screen since that can interfere with framerate.

* Use [] array not the Collections (ArrayList, etc) as they alloc. Don't use enum. Don't use Array.sort() Consider using an alternate framework that doesn't use allocations, or does use a pool .. to replace Collections.

[ncr100]

@ncr100 * Don't call functions if possible. Use static functions. Don't call through interfaces (30% slower). Virtual functions ok, but not interface, nor jni. So no .get nor .set if possible. Make fields public. Avoid calling lots and lots of native functions - calling is slow even though the native functions themselves are quick.

* Use final keyword. Use android Log.d instead of System.out.println.

[ncr100]

@ncr100 * Use TraceView - the android sdk's profiling tool.

* Use SpriteMethodTest sample app to try out the canvas verus opengl speed. opengl draw_texture 2d can be 3x faster than using canvas. most devices today support opengl 1.1+. VBO can be useful too since you can use UV's to build your scene and use fewer draw jni calls. ATITC texture compression can help improve performance on devices that support it.

[ncr100]

Respond to this video... * Touch events come in floods - try sleeping for 16ms in the onTouch callback to slow that down

* Take time to polish your game - appeal to picky users with higher quality stuff.

[MediaFilter]

He looks a bit like the young Jimmy Page :)

[A1260T]

pruett is a true public speaker for all coders, awesomeness, better shirt than that 2010 one, lol - gaz.

[Appfyr]

It would be really really cool if we could download the presentation to remember, show others, read again once!

[abid1770]

Appiction isn't your ordinary mobile application development company. We’re an App Development Studio with ownership in 50+ applications. We turn a large number of potential clients away because we don't build low-cost and non-performing apps. We build quality. If success is important to you, and you want your idea to flourish, we're your app development partner.

[shavinda34]

Do you have iPhone app idea? You can make your own iPhone app with a software called AppWizard in less than 30 minutes

[sweet1553]

Do you have iPhone app idea? You can make your own iPhone app with a software called AppWizard in less than 30 minutes.

[Frony120]

very good iPhone.

[tuhin5858]

"Do you have iPhone app idea? You can make your own iPhone app with a software called AppWizard in less than 30 minutes"

[czsohel]

"Do you have iPhone app idea? I heard you can make your own iPhone app with a software called AppWizard in less than 30 minutes"

[Liiinusen]

DAMN that game sucked so hard.

[calvino123456]

this guy talks EXACTLY like Tony Stark... Robert Downey Jr.'s illegitimate son much?

[v4mpir33d]

There's lie, big lie and statistic 0:04:22. Google trying to create a boom for cell phone gaming? Good luck, Google agent!.. U imposter of a greasy haired nerd! :)

[RoyBarina]

subtitles are out of sync.. and disappear too fast

[grimlock047]

"writing java code that is fast"

Java code? o.0

[hej100]

@grimlock047

programming language

like c, c++...

[Flightmare]

@grimlock047 Yes, the android platform is able to run Java code natively so you do not have the virtual machine overhead.

[veQue2]

What does he mean when he says don't use functions? 34:35 how in the world can I make a game without calling functions?

[zyrgzyrg]

@veQue2 Hey Just remove you function call from you function call So you can inline while you inline!

(Oh yes, Uncle Bob would be mad. I mean realy MAD)

[euroq]

@veQue2 It's half a joke, but half serious: The less function calls you make, the more optimized it is. In other words, don't put all of your logic into dozens of Java methods; try to put all of your logic into as few methods as possible. This only applies for code that needs to be optimized; i.e. a game loop which is called 60 times a second.

[euroq]

@veQue2 It's half a joke, but half serious: The less function calls you make, the more optimized it is. In other words, don't put all of your logic into dozens of Java methods; try to put all of your logic into as few methods as possible. This only applies for code that needs to be optimized; i.e. a game loop which is called 60 times a second.

[arup02]

best video on youtube.

[Yekolf]

thanks exactly what i was looking for

[sskenth]

I really would enjoy watching this, but the sound seems to be corrupt! Please re-upload or fix, as everything said is invaluable.

[zyrgzyrg]

Nice

[fitz297]

Great talk, thanks!~

[MendaSpain]

I can't here well the sound. It seems it's broken.

[ShiftyMcCan]

Good presentation, but I have sinking feeling that he may be a vampire...

[Virginityrocks]

Wow. This guy is my hero. He's wearing a dork sweater, has pale skin and greasy hair. You know this guy is legit.

[restf0rm]

@Virginityrocks Dork? :p you must be American >.<

[priestwhitebrows]

@Virginityrocks

Don't forget...he also speaks Japanese. *facepalm* *shakes head*

[TheHumansoverMoney]

@priestwhitebrows

he does ?, he might wanna check my anime video,and tell me if the subs are terrible..

i have no clue..

[Dracula0000]

Really cool presentation, helps put things into perspective for those of us considering developing on Android. I enjoyed the jokes :)

[grenadei]

The dude is scary. Ultimate 'pick me' mentality with a head on his shoulders.

[ytvoice1]

Generally all Google speakers are sympatic. Because they have so high knowledge.

BTW, it helps seeing it a second time. The subs are out of sync thgough, theyre not helping if english is not the native language.

[TotalGameMaster]

Hey google Make youtube videos longer we know u have bandwidth problems but look there are thousands of youtube partners u guys make billions every day i mean WTF let us have at least 1 hour long videos

[DoozyJr]

@avingard hahahaha, your comment to him made me laugh

[jasongosen]

Good talk, I think he just convinced me not to make games in Java. :P

[kassem435]

@avingard um explain what you mean?

[TehNetherlands]

Awesome. Very useful insights and tips. Thanks!

[kassem435]

it's annoying to listen at hes to nervous

[ytvoice1]

@kassem435 It sounds like a good speech, but damn he is speaking very (too) fast.

I understand, if he is not used to speaking, after a while it becomes hard, because there is no reaction from the crowd for some time. It can mean they are interested and listening, but he needs a reaction from them. Maybe to relax himself he shut put in a joke of some kind, so he can hear people laugh.

Anyways, he is young, I think he will learn. Everyone are nerveous the first times..

[TotalGameMaster]

@ytvoice1 i do agree if i was in his position i would have let some jokes out just to get a reaction

[kirika727]

@kassem435

but, he sounds sympathic

[overtext]

interesting...i wish i knew what he was talking about :-/

[0rmick]

@overtext Take any basic CS course and trust me, you will.

[overtext]

@0rmick thanks I'll look into it

[jasooon85]

thanks for sharing

[NeverForgetWizet]

Freaking movies on Youtube...

[looris]

is there a transcript somewhere?

[Flashtoorev]

The subs suck. I like all GoogleDevs vids. This is really helpful.

[hardToSignUpHere]

is it only for me or the sounds is quite low quality and quiet?

[uluvatc]

@hardToSignUpHere Fine for me!

[zxjayzhou]

very good!

[surfdudezuri]

he says "um" a lot...

[iamhonestjohn]

Screw Google.

[pliablemammal]

lol they own your comment.

[iamhonestjohn]

@pliablemammal lol true! They can gladly have it. Plenty more where than came from. In ten years time, if Bing doesn't beat em, comments like that will probably get people killed by a Google laser built into their laptop.

[RedClownKnight]

Maybe it's Java.

Wonder when someone is going to release a C/C++ tools

[CrackNImO]

@carmscarms so?

[RedClownKnight]

This was very helpful for me

since I'm also working on android games.

and like what he said.

I also never wrote an java app before

[maxood007]

@RedClownKnight What are you really working on. We have been working on android since 4 months. Made a plenty of database apps. Now we have begun working on games.

Have you looked into game engines like Rokon?

[squabsquab]

i ran his frame rate tester on my droid, and canvas had better frame rate than the 3 opengl options

[Jaycephus01]

Yeah, I'm trying to find out what's up with that, too. Some posts online say that OGL configs in the droid need tweaking. On the other hand, the program behaved the same in the emulator.

[frenchmen77]

I would be interested in seeing his source code...

[maxood007]

@frenchmen77 me too

[ssankoo]

Its a really cool presentation, but he could talk a little slower at some points.. Nevertheless cool!

[papucimurdari]

I'm definitely getting an Androit :)

[tedkarenm2]

This was great help. Thanks.

[SirEricCartman]

What do you mean "were?" Humans are continually evolving.

[MrCricketFlash]

This guy talks fast and acts slow.

I think he uses the cocaine

[neonstrike]

this video is waaaaaaaay to quiet.

[dansal88]

Antes estos videos tenían subtítulos cierto?...

[SirEricCartman]

I tried to add comment but mistakenly reported this as obscene -- it's not, sorry.

I didn't see the URI at the end of this video, and would like to look at it...

My feedback: This video excellent. Very informative. The only thing that could make it better is if the speaker had another half an hour or so to answer all the questions from the audience.

I'm keen to learn OpenGL in Java for Android now, and my next phone will have Android so that I can experiment.

[orlandomei]

This video is going to save me a lot of pain for my next development. Gracias Chris, VBO's seemed like the thing that will work for me.

[polishboy42]

who actually watched the whole thing

[reeceTHEmelter123]

meeeeeeeeeeeeeeeeeeeeeeeeeeeee­e not

[SirEricCartman]

I watched the whole thing, although I paused it part way through to go have dinner. It was a very informative presentation.

[gorgeconowitz]

ling ass vid

[poodlelord]

ive had the problem with frame rate in flash befor.

so its not just an android problem

[kubevubin]

I'm getting an HTC Droid Eris. I kinda wonder how game input will work, since it has no hardware keyboard. It only has the touch screen, two regular buttons (Send and End), a trackball and some touch buttons. Wouldn't using the screen for input during a game bog it down as was mentioned toward the end of the presentation, or are there ways to simplify the events that'd take place as you touched the screen?

[SirEricCartman]

Maybe the touch-screen just acts like a mouse? That's how it works on other computers.

[alejorasanz]

gay... ke desocupado elke vea esta mierda!!

[virtuous8]

im a man, but i find this guy is considerably hot... I am not gay or anything. but.. he is hot.

[jimmyjay122]

Sorry dude, but you are definitely gay

[brechtjah]

No, you're gay alright.

[iPCAdministrator]

So true about making games, determining which players play what and how to compose the AI, great presentation, coding games on android is hard though I attempted coding, HARD

[VanDude245]

1 hour and 1 min, wow

[UKLooney]

Thanks, save around 20% cpu time in my game thread by applying some of the techniques you mention...

[haguylerman]

Unclear speech to fast slow down don't get stressed

[Holokauston]

The reason it's stressed is that he has to cover lots of information in one hour

[Sidsix5555]

"Muscle bound space marines who have amnesia"!!! LMAO!

[MSJDesign]

what about PC games? Console is old.

[SirEricCartman]

Console is "old?" Is "old" a bad thing, or a good thing? I like console games, especially those that use ASCII art, and I also value both new and old, so I'm confused by your comment.

Could you elaborate on what you're really asking? Thanks.

[Playver1337]

hahaha...eh...eh...eh....eh...­eh...

[FranLsk]

"yeah, casual-gaming is a good idea. We should stop caring about hardcore gamers and make some colorful and full-of-kid-stuff games!!!"

¬¬

[SirEricCartman]

Actually, I agree with the idea of bringing back the older style of games. All these big 3D games that are available today are mostly the same, with the same game mechanics, albeit with different textures, characters, weapons, etc.

The games from the 1980s provided true variation that truly tickled our brains, which nearly all modern games fail to do. I would love to see more 1980s spirit in gaming come back, and I hope Android will be the platform to "trigger" this.

[neonstrike]

...stfu.

[SirEricCartman]

That's not even a word.  You want to try again?

[neonstrike]

S.T.F.U.!

[SirEricCartman]

Oh, I see, that was an acronym! I think I can figure this one out 50%...

If the first two letters stand for Scott Tinnerman, the last two stand for...

Hmm, I dunno. What would they could be for? Hmm.

Would you like some home made soup?

[neonstrike]

tEnOrman. Now S.T.F.U.

[SirEricCartman]

Hey, you will respect my authoritah! I will tell you what to do, not the other way around!

[neonstrike]

No. S.T.F.U.

[SirEricCartman]

You keep writing the STFU acronym, but I only have a guess for what 50% of it means. You are a terrible communicator.

[neonstrike]

No I mean it. S.T.F.U.

[hitchen1]

S.T.F.U, Noone wants to see you typing 'STFU' repeatedly. Fagtard.

[neonstrike]

S.T.F.U. 

Tardfag.

[HonestGamer1]

Great presentation. Helped me a lot.

[soundmachine6]

He is probebly the ultimate nerd XD But it was a cool speech, nice to see how he pot some jokes in an otherwise kinda boring talk

[Timcookie321]

is this the creator of google

[SirEricCartman]

No.

[delphiking]

Great talk, learned some interessting stuff :) *starting eclipse*

[TheTRoxby123]

omg its an hour long

[Unrealshade]

great talk! enjoyed all of 60 minutes! though i don't know much about programming

[crazychris66]

45 days ago, and still no source code online... :-(

c'm on -- release it guys!

[gunston]

Hi - nice talk, lots of detail but... did the code get posted anywhere. Many thanks.

[jimmacfx]

Audio is really odd. It sounds all garbled (androidy ;) but when I plug in headphones it's all fine. Pulse audio to blame again? Linux audio stack in general? ;)

[Ace2016]

This happens to me too when the speakers aren't plugged in properly, i use vista

[DarkBytePH]

Most of the I/O videos are very low at volume, so i have to download them and play with an external player which can do amplification. Although it's very good that all the session go online on YouTube.

I wish i can have a HTC Magic too so i can start developing for a real hardware. :|

[rikhemsley]

Very weird audio

[microsnot1900]

Heheh... Placed an order for a HTC Magic yesterday. Oh happy day! :o) I hope I get it by friday. It seems to be one heck of a phone.