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JUNE 2007

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REGULARS

EdsNote.........................................................................................P03

News...............................................................................................P04

FEATURE

TheMakingof.S.C.A.G...................................................................P05

OPINION

TheSandtrap...................................................................................P09

CanGameDevelopersLearnfromGenetics?................................P10

DESIGN

BlenderIntermediateTutorial:CreatingExplosions.........................P12

TakingtheBluePillfor:GameMaker...............................................P15

ABeginnersGuidetoMakingGames:Part1..................................P16

PROJECTS

RoachToaster2:BigCity................................................................P21

TECH

GameCodingwithTrigonometry:Part1.........................................P22

HISTORY

TheHistoryofI-ImaginePart5:TheFirst9Months.......................P24

TAIL PIECE

JohannesburgdevLAN....................................................................P27

CONTENTS WHATS INSIDE

05

15

24

27

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EDS NOTE THE BIG CHIEF

AninterestinglittlethingiepoppedupontheGame.Devforumstheotherday.Amidstallthehype,hubbuband

competitionentriesforComp15(hey,R10000,remember?)thathavebeenclutteringthecommunityasof

late,oneofourmembersburstinonthelatestDev.Magthreadanddrewourattentiontothefactthathesaw

someGame.Devadsonthetelly.Prettyawesome,Imustsay!Werestokedthatthegrouphascomesofar

inthisrelativelyshortspaceoftime,andkudosmustbegiventothecommunitysfounderandleader,DannyIve-worked-

my-ass-offDay,knowntomostasdislekcia.

ThiskindagotmethinkingthatmaybethismagdoesntadvertiseitslinktotheGame.Devgroupenough.Itsalwaysbeen

greatthatthemembershaveworkedautonomouslyonthispublicationformorethanayearnow,andweveneverbeen

restrictedbythehigh-upsregardingcontentdecisionsandhowmuchextraicecreamwegetonFridays(itsaperkforloyal

staffmembers,Ilienot).But,asflatteringasitistohavesomepeopleforgetthatDev.MagisjustacoginthebigGame.

Devmachine,maybeitstimetopayhomagedirectlytoouralmamateroverthesenextfewissues.Thankyou,Mommy.

Youvegivenbirthtoabeautifulbabyzine.

Onasimilarnote,someofourwritershavebroughtuptheconcernthatperhapswerelosingtouchwithouroriginalethos.

Nomatterwhatelseweputinourpages,thiszinewasultimatelycreatedtoserveasaguidethosewhoweretakingtheir

firsttentativestepsonthatscarygamedevelopmentroadsobygolly,weregonnastickwiththatgoal! Tothisend,weve

donethreethingsforyou,ourreaders:

1.WeveintroducedaBluePillarticleseriesintheDesignsection.Everymonth,wellbetakingalookatonegame

developmentproduct.Welltellpeoplewhatitis,howitworks,whereallthebesttutorialscanbefoundandwhyitsa

goodideatogetstartedwithit.

2.WeveestablishedourownseriesofGameMakertutorialstohelpanybodywhostillisntconvincedbywhattheyhear

abouttheproductseaseofuse.Itsablast,seriously!

3.Werenowtakingcaretorefertobackissuesforthebeginningsofarticleseriesoronce-offtutorials,sothatanybody

confusedbythestufftheyreadinherecaneasilyflipbacktoapreviouseditionandbeenlightened.

Weredoingourbesttomakethisworkoutaswellaspossible,sobesuretosendusyourfeedbackandtelluswhatyou

thinkofthechanges!

Editor

Rodain Nandrew Joubert

EDITOR

Rodain Nandrew Joubert

DEPUTY EDITOR

Claudio Chippit de Sa

SUB EDITOR

Tarryn Azimuth van der Byl

DESIGNERS

Brandon Cyberninja Rajkumar

Geoff GeometriX Burrows

MARKETING

Bernard Mushi Mushi Boshoff

Andre Fengol Odendaal

WRITERS

Simon Tr00jg de la Rouviere

Ricky Insomniac Abell

William Cairnswm Cairns

Danny Dislekcia Day

Andre Fengol Odendaal

Heinrich Himmler RallMatt Flint Benic

Luke Coolhand Lamothe

Stefan ?rman van der Vyver

Gareth Gazza_N Wilcock

WEBSITE DESIGNER

Robbie Squid Fraser

WEBSITE

www.devmag.org.za

EMAIL

[email protected]

This magazine is a project of the

South African Game.Dev commu-

nity. Visit us at:

www.gamedotdev.co.za .

All images used in the mag are

copyright and belong to their re-spective owners. If you try and

claim otherwise, you dont get to

play .S.C.A.G....

... ever!

WHOOPS!

Well,arentwejustsillysillies?Lastedition,we

failedtomentionthatthisDBmodel(and,well,all

oftheotherDBmodelsyousee)aredonecourtesy

ofoneGeoffGeometriXBurrows.Hedidapretty

swelljobonem,too.Thanks,Geoff!

DEV.MAG ISSUE 143

This months opinion columnists:

Rodain Nandrew JoubertSimon Tr00jg de la Rouviere

This months PGD contributors:

Michiel NecroDOME Gijbels

Frank Mad Woody van Gent

www.pascalgamedevelopment.com

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Reminder for Comp 15

http://www.gamedotdev.co.za/

Thatsright,acheekylittlereminderthatthecompetitionisstillonandstillacceptingnew

entrants!Gamemakersextraordinairehaveonemonthlefttogetcrackingontheirown

masterpieces based around an educational theme and get their piece of

R10000! CheckouttheGame.Devwebsiteandforums formoredetailsonentering.

Game Addiction Discussed

http://www.gamedev.net/community/forums/topic.asp?topic_id=453210

TheAmericanMedicalAssociationrecentlyheldadiscus-

sionabouttheseverityofgameaddictionandwhetheror

notitcanbeconsideredaformalpsychologicaldisorder.

Thefinaldecisionwasagainstlabellingitassuch,butonly

becauseitwasfeltthatmoreresearchneededtobedone

inthearea.Gamedev.nethasalinktothedocumentout-

liningtheissue,anditlookslikethemedicalworldisgoing

tobepayingmuchcloserattentiontogamingfromnowon.

NEWS HEADLINES

Doritos game design

http://www.unlockxbox.com/

Thelatestgame-makinginitiativeonthe

Xboxisbeingspearheadedby...tortilla

chips?Well,thatseemstobethecase,

anditsaninterestingchallenge,tosay

theleast.Thepremiseissimple:submit

adesignideaforaDoritos-basedgame

which has the chance of being devel-

opedintoaXboxLiveArcadegame.If

you happen to have a US citizenship

lyingaround,takeastabatityourself,

orwatchfromtheshadowstoseewhat

happens with whats proclaimed to

be the first user-generated Xbox 360

game.

Nintendo says yes to indie developers

http://gizmodo.com/gadgets/wiiiiiiiii!/nintendo-opens-wii-to-indy-developers-272717.php

Traditionally,Nintendohaskeptitsdoorsclosedtothirdpartyand

indiedevelopers.However,arecentannouncementbythecom-

panyhas turned that ideaonitsheadandbroughthopetoWii

enthusiastsandaviddevelopers.WiiWare,agamedistribution

servicecomparabletotheoneofferedbyXboxLive,issettoal-

lowsmallercompaniesachancetogettheirgamestothepublic

withauser-friendlysalessystem.Althoughitseemsunlikelythat

thiswillopenupWiidevelopmenttothemanonthestreet,were

holdingthumbsforit.

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programThe_Making_of_.S.C.A.G.;

implementation

constructorCreate();

begin

Thisarticlewilldescribein-depthhowwemade

thegame.S.C.A.G..Whenwestartedwiththe

engineayearandahalfago,theoriginalideawastomakeafirstpersonshooter.Whenwe

finallyhadauserfriendlyeditor,thePGDcom-

petition(BigBoss)crossedourpathandwede-

cidedtocreateagamethatlookedliketheold

arcadegameRaptor:CalloftheShadows.

end;

procedureInit();

begin

Thefirstthingwedidwastocreateanewproj-

ect,andincludeourNecro3Dgameengineinit.

Thiswasagoodtestforustoseeifweactually

THE MAKING OF SCAGby NecroSOFT

FEATURE SHOOT. FLY. SHOOT SOME MORE.

Wejustcantseemtogetenoughofthose

Pascal guys right now. This month, we

sport a postmortemofone ofthe games

built by the Pascal Game Development

teamknown asNecroSOFT. Theycallit

.S.C.A.G.. Its slick, its fancyanditwon

2nd place in the 2006 PGD Big Boss

competition, so we thought it would be

worthwhileto nagthem fora juicyarticle.

Ofcourse,theseguysdontthinklikemost

people,sowhatweendedupwithwasa

cryptic list of Pascal code instead of the

usualEnglish. Fortunately for you, dearreader,wemadeafaireffortattranslation...

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couldmakeagamewiththeengine.Wewere

alsoabletoseeiftheeditorwasasuserfriendly

aswewantedit tobe.When our enginewas

successfully implemented, itwastime to load

alow-polyshipandafewcubestogetproperhandlingfortheplayersship.Inthisphasewe

alsogotthegreatideatodosomethingmore

then a 2DRaptor game ina 3Dengine.We

decidedtomakeagamethathadaside-view,

andatop-downview.Withthisinourminds,we

startedcreatinglevelsandenemies.

end;

functionLevel_Design()

begin

Forthecompetitionwehadtomakethreelev-

els.Wellwemadefour just for fun!Afterthe

competitionweexpandedittofourteen,divided

intofourdifferentzonesplusonebonuslevel.

Thefirstlevelwasacity.Becausewehadno

terrainengineyet,weusedplanestomakethe

cityroad.Inafewplacesinthelevelweadded

somebigsmokeparticlesforsomereallynice

effects.Thiswill givethe player theidea that

itsverywindyinthetownandthatthecityis

deserted.Itseasytocreate,andgivesagreat

environmenttothegame.

Thetop-down,andside-viewcannotbechosen

bytheplayer,butaremarkedinthemap.This

isbecausewehadtoaligntheenemiesontwo

differentaxesforthetwoviewmodes.Allthe

enemieswereplacedwithoureditor.Wecan

tellyouthis-itwasonehellofajobtogetit

done.Itdidnttakeverylongbeforewecreated

acopyandpastefunctionforthisintheeditor.


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Whentheterrainenginewasdone,itwasreally

easytoimportheight-mapsandspeedupthe

leveldesign.A very importantthing to create

therightenvironmentislight.Insteadofusing

onegloballight,weusedalotofsmalllights.Themostimportantthingisthatallthoselights

weplaced had different colors. For example,

inthelavalevelsweusedalotofyellowand

redlightstomaketheuglygreylevelsmoreat-

tractive.Wehadasmallproblemwiththislevel

becausewehadalotofaliasinggoingonatthe

edgesofthelavaandtheterrain.Tosaveyou

guysalotoftimewhenyouhavethisproblem,

its caused bythe Z buffer and theminimum

cameradistance.

Anotherfunthingaboutthelavalevelthatwe

createdafterthecompetitionwastherocksthat

arefallingdown.Thisistheonlyplacewhere

weusedtheNewton Physics Engine thatwe

implementedintoourengine.

Inmostof thelevelsweusedmulti-texturing.

Thismeansyoucanplacetwoormoredifferent

texturesoneachotherwithablendingeffecton

it.Inoureditorwemadeafeatureinthetexture

browsertoeasilydothis.Justcreateanempty

texturewith a sizeand load the texturesyou

wanttouse.Youcanseethiseffectintheice

level,aswellasthemirroringonthebuildings

ofthecitylevel.

end;

functionWeapons();

begin

The most fun part of creating a game is of

course adding awesomeweapons.The inter-

estingthingofourgameisthatsomeweapons

havetwodifferentbehaviors.Forexamplethe

rockets will fall down a little bit in side-view,

andthenintop-downview,theywillgotooutto

thesidesabitonthescreen.Wealsomadea

weaponcalledtheDrunkenpod.Itfiresabunch

ofsmall rockets thatwillfly allover theplace

--becausetheyredrunk,ofcourse.Eachrocket


leavesasmalltrailwhichcreatesareallycool

effect.We made thisby simply stickingsome

particlestogether.

end;

functionShip_Modeling();

begin

First, I haveto saythat wearenotgreat de-

signers.Ourinspirationcamespecificallyfrom

Raptor.Wealsolookedforsomeshipsonthe

internetforideasandworked themoutin 3D

max,butwithourowntwist,ofcourse.Theidea

oftheSharkfighter(yellow,redenemy)wascre-

atedfromanoldGameBoyClassicgame(dont

rememberthe name).Butduringthe creation

wechangeditsomuchitwasacompletelynew

fighter.Afterwecreatedthemodelswehadto

doourfavoritejob-texturing.Wellwemadeit,

andlooksgood,butitsnotthemostfunpartto

doandverytimeconsuming.

end;

functionSoundtrack;

begin

We made four different soundtracks for

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.S.C.A.G..Thefirstideawastoletafriendof

oursmakeitwiththehelpofhisband.Unfor-

tunatelyhedidnthavethetimetodoit,sowe

decidedtomakeitourselves.Weusedavery

oldprogramfrom1996calledNewBeat.Itoffers

alotofdifferentsamplesdividedintosamples

from 2, 4 and 8 seconds. With thisyou can

makegreatsongsifyouuseitright.Itcreated

justwhatwewanted,aretrostylesoundtrack.

Onlykeep inmind thatthesamplesshouldnt

conflictwitheachother.

Toplaythesoundtrackandsoundeffects,we

hadfirstusedtheOmegaDirectXSDKforDel-

phi,butsincethereleaseofVistawenoticedit

wasntVistacompatible.Sowethendecidedto

useanotherSDKandasresult,wecannowsay

that.S.C.A.G.isVistacompatible.Itnowalso

supports the Doppler effect, but is not used.

Yet...:)

end;

functionMenu();

begin

Forthemenuwecreatedanewmenuengine

that supports drag-able panels and custom

fonts.Fontsin.S.C.A.G.arecreatedatruntime

tosavediskspace.Themenuitselfwascreated

usingbuttons.Eventhebigcaptionlogoontop

ofthemenuwascreatedusingabuttonwithno

clickeventandtwoofthesameimagessoyou

wontnoticeitwhenyouhoveryourmouseover

it.Thescrollingtextinthecreditswindowwas

madewitharendertargetthatwasplacedon

abutton,whichinturnwasplacedonthemain

creditspanel.Itgivesanicelooktoseecredits

scrollinginsideawindow.

end;

functionThe_New_Way();

begin

OurNecro3Dgameengineisgreat,butthereis

alwaysroomforimprovement.Thatswhyafter

twogamesintheNecro3Dgameengine,weare

nowbusywiththeNecro3Dgameenginever-

sion2.Themainimprovementofthisnewen-gineisthatitwillbefullydynamic.Wearegoing

touseseparatemodulesthatareloadedinthe

enginelikeapluginsystem.Examplesofsome

ofthemodulesare;theRendermodule,Sound

module,Physicsmodule,andsoon.Withthis

structurewecaneasily change, forexample,

therenderingwithDirectX10orOpenGL,with-

outrewritingthewholegameengine.Thisalso

meansthatwecaneasilyupgradeagamewith

anewphysicsengine.Itsalittlemorecomplex

tomake,butwhenitsdonewellhaveagreatly

improved,fullydynamicengine.

The workofthisnewengine progresseswell

andwearealreadyabletoload3Dworldsand

compile shaders --something the old engine

couldntdo.Alsotheeditorisgoingtobevery

different.Insteadofthefourviewsections--top,

left,frontand3D--wearenowgoingtouseone


single3Dview.Weareveryexcitedaboutour

newengineandhopetobeabletoshowyou

thefirstgamesmadewithitsoon.

end;

procedureCleanup();

begin

With.S.C.A.G.,wemadeagreatgameandfin-

ishedsecondinthePascalGameDevelopment

AnnualCompetition.Wecansaythatwehada

lotoffunmaking.S.C.A.G.andareplanningto

tryandsellthiswonderfulgame.Keepinmind

thatthisisnottheend,butonlythebeginning.Wewillcontinuemaking gamesandwith the

newengine,wehopetobeabletocreatemore

qualitygamesthenever.Andwhoknows,may-

beyoullseea.S.C.A.G.2?;)

Print(Endofline.);

end;

//Giveusavisitat

//http://necrodome.homeftp.net/

end.

DEV.MAG ISSUE 148

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THE SANDTRAP

Yeah,okay,soweallstandinaweofcreativityandfreedominvideogames,

right? I mean, games are evolving

from the droll, go-here-do-this linear hum-

drumof yesteryearinto theflexible,free-form

sandboxesthatweremetwithtoday.Theyre

morelikethetoysthattheyshouldbe,right?

Riiiiiiight.

Popular opinion seemsto bethatgames like

TheSims,BlackandWhiteand,toalesserex-

tent,Fable are usheringin the golden age of

gaminganeraofvirtualworldswhichhaveac-

tivitiesandobjectivesthatgobeyondthebasic

goalsofthegameitself.Inmoreextremecases,

user-definedgoalsserveastheonlyobjectives

inthegame.So,woohoo!Youhaveultimate

poweroveryourdestiny!Aintthatjustdandy?

Well, while this sounds great and all, I think

Imgoingtostepforwardhereandrisksound-

inglikethatproverbialoldmanontheporch.I

dontthinkthatthisnewwaveofgamesareall

theyrecutouttobe.Theymayappealmore

toanewmassmarket,butasfarasImcon-

cerned,games aredefinedby rulesand goals

setbythedevelopermuchinthesameway

thatmovieplotsarewrittenbythoseblokesin

Hollywoodandnotthepeoplesittinginthecine-

ma.Heck,evenajokehasadefinedpunchline.

Imagine how dreadfully boring it would be if

yourfriendwalkedovertoyouandsaid,Knock

knock,yougettheideanow.Finishityourself.

IveplayedTheSimsmyself.Gotratherboredafterawhile,soIwentontobuyanexpansion

packortwo(especiallysinceoneofthemhad

thoseadorablelittlepetsinit).Thosedidntlast

muchlonger.IeventuallycluedupastowhyI

wasntenjoyingthegametherewasnodefined

challengesforme.IfIgotrich,Igotrich.IfIbe-

camefitterorgotnewemployment,goodonme.

Theresimplydidnotseemtobeenoughofthe

gamesaying,Heygreat!Youdidasweetjob!

Heck,IalsoplayedFablewentandboughta

housein-game,evengotmarried.Theresultwas

thatInowhadawifewithalittleheartaboveher

headwheneverIdecidedtostepbackintothat

oneparticularpartofthegame.Andforwhat

OPINION WHAT YOURE THINKING

purpose?Shedidnthelpmekillmonsters,she

didntunlockanybonuses,shehardlyevenap-

pearedunlessIwentoutofmywaytofindher.

Itallseemedmerelyforthekudosofhavinga

wife.Aremoderngamersreallydrawntothat?

Dontget mewrong. I thinksandboxgames

areimportant,and mostgamescontainsome

concepts of user-defined goals. Still, I think

itsimportantforustopayheedtotheadvan-

tages presented by a well-scripted and well-

ordered games that provide rewards which

are ... well, truly rewarding. Just a thought.

NANDREW

DEV.MAG ISSUE 149

The Dev.Mag staff does not expressly support or agree with the views of guest columnists in this section.

In fact, the Dev.Mag staff does not expressly support or agree with the views of Dev.Mag staff writers in this section.

Its a crazy world, isnt it?

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Can Game

Developers learn

from Genetics?

Inmyquestto discoverwhycertainoriginalgamesgetthe limelightwhileotheroriginal

gamesgetlost inthe recessesofthe web, I

stumbledupontheanswer.

It happenedwhile I was watchingmy favourite

show,Heroes. If you dont know, Heroes is all

about seemingly normal people trying to cope

withtheirspecialpowersin their everyday lives.

Thenarrator of theshowspeaksabout thecon-

ceptof evolutiona lot.So being thepersonthat

Iam,IwikiedHeroesandEvolution.Idiscovered

aninterestingandtruephenomenoninevolution.

When there is a huge number of a species

(like humans), any new mutation will be liter-

allydrownedoutbysheernumberofpeoplewho

simply donot have that mutation. The chances

that this new mutation will be carried to new

generations are incredibly remote. A new mu-

tation will have a higher chance to get carried

on tonew generations insmall closedsocieties.

Iimmediatelydrewacomparisontogames-whatare

thechancesthatanoriginalgamegetsnoticedand

acceptedassomethinggreat?Verysmall,simply

becauseitisdifferenttoeverythingelseoutthere.

Icanhearyouasking,Butifagameisoriginal,

doesnt it then stand out among the masses?

Yesit does,butagainwedrawa comparison to

genetics.Ifsomeonewithanewmutationoccurs,

wewould be instinctively wary.An extreme ex-

ample is thecase that someonemutates a third

arm.Lookat allthepossibilitiesandadvantages

of a third arm! But lets be serious here - who

wouldgooutwithsomeonewhohasathirdarm?

SoIcomebacktomyoriginalquestion.Whydo

some original games fare better than others?

Ill explain it by another example. If Super-

man (who has awesome powers) gets tired

of Lois Lane, he will have plenty of girls will-

ing to have his babies. It is instinctively viable.

Now how do we distinguish between third-arm

games and Superman games? Is your original

game third-arm or Superman? If its a Super-

mangame,you wouldntbe reading this - youd

be takingaSundaydrive inyourFerrari. I dont

knowthe answer,but I have the solutionto get

OPINION WHAT YOURE THINKING

yourthird-armgameorSupermangamenoticed.

Thegreatdifferencebetweengeneticsandgame

developingisthatwecanchoosethesenewmuta-

tionsinourgames.Ifmoreandmorepeoplemutate

thirdarms,thephenomenonwillbecomeaccepted

insocietyandbecarriedovertofuturegenerations.

So,whatisthesolutionhere?Ifyouhaveanorigi-

nalgamethatdoesnotseemtogetnoticed,you

shouldkeep floggingit everywhereandproduce

sequels with the same gameplay. If more and

morepeopleseeyouroriginalgameanditsvari-

ants,itWILLbecomerecognisedandtalkedabout.

TakeTeam17sWormsasabrilliantexample.All

they have done is developWormsafterWorms.

Who remembers the first worms when it came

out?Back then, no-one reallyknew about it,but

nowitsgrossinghugesaleswithitslatestincarna-

tiononX-boxLiveArcade.Theyjustkeptgoing.

Itsassimpleasthat.Justkeepgoing.

TROOJG

DEV.MAG ISSUE 1410

The Dev.Mag staff does not expressly support or agree with the views of guest columnists in this section.

In fact, the Dev.Mag staff does not expressly support or agree with the views of Dev.Mag staff writers in this section.

Its a crazy world, isnt it?

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MAKE A GAMEAND GETYOUR

PIECE OF

R10 000Here at Game.Dev, we believe that games are more than just entertainment or a silly fad

games can (and will) change the world and make a difference. Mindset Learn are keen on doingjust that, making a difference. So theyre challenging us and you to produce the next gen-

eration of entertaining and meaningful games. That challenge takes the form of:

R5000 for first place,R2500 for second place,R1500 for third place and

R1000 for the best new entrant.

So all you have to do now to get a shot at that prize money is put together a game thats fun

and focuses on a concept you enjoyed or found challenging at school. You dont need to pro-

duce a fully fledged educational experience, in fact were looking for quite the opposite: fun

games that are enjoyable because theyre well-designed and entertaining, you just happen to

be playing within rules or a setting that match something youve learned. Think guerrilla learn-

ing and youre on the right track!

The competition begins on 1 June 2007, and the deadline for entries is 31 July 2007. Thats two

months that you have to make the ultimate game and win some big money!

For more details, head on over to the Game.Dev website at http://www.gamedotdev.co.za

8/14/2019 Dev.Mag - 14

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12

BLENDER INTERMEDIATE TUTORIAL:

Creating explosions with Blender 3D

DESIGN ENTER THE 3D WORLD

swithprevioustutorials,Ineedtostress

the factthat thebasicBlender interface

has already been discussed within

previous releases of Dev.Mag. I wil l not

thereforeexplaineverysinglestepoftheway.

Thereareplentyofinterface-relatedresources

on-line.

Blender3D hasan integrated particlesystemthat can render production quality special

effects. One possible use for this particle

system is to render a particle system that

simulates an explosion through animated

colourandtransparencyparameters.

Therenderedsequencecanthenbecompiled/

compositedasamovieclip,animatedGIF,orin

anywaythatyourspecificsoftwarepackagewill

handle images with sequential numbers.

Hence,ananimatedexplosion.

Thefieldofspecialeffectsisbiggerthanashort

tutorial,soexpecttofind:

Thebasicsforsettingupaparticlesystem

Basicanimationofcolourparameters

Basicintroductiontotransparencyfor

Blenderparticles

Particle systems can produce spectacular

effects,dependingonthetimeyouarewillingto

spendtweakingit.

So,firstthingsfirst.Wehavetoplanthisthing,

sinceithastofitintoagamesomehow.

Isuggestdoinganexplosion:

That will be an explosion for a scrolling

top-downshootinggame

That starts and completes the animation

withintwoseconds(Iwillworkwith25frames

persecond)

Two seconds of animation amounts to 50

frames at 25fps, and I will plan the colour

changesofmyparticlestofitintothattimeframe.

Iwillsetmycolouranimationtogofrominitial

BLACKsmoke, tobright hot RED, toflaming

ORANGE,andendingoffwithGREYsmoke.Timing will be set as indicated in the image

below.

Wewillcreate:

Anobjectthatwillshootoutparticles

Createatexturefortheparticles(mainlya

smoky,see-throughtypeofeffect)

Keyframethecolourchanges

Positionacameratodocumentthe

explosion

Render50frames

Particleswillbegenerated(inthiscase)froma

meshobject.Wewillshapetheobjectsothat

theparticlesdonotsimplyflyoutinastraight

line.Speedoftheparticlesisdeterminedbythe

menusettings.

Of course we also have to tell the particles

when toappear,how long theywill last,and

howlongtheywillbeemittedfor.

Forexample,wemightsaythattheparticleswill

bethrownoutoftheobject(emitter)withinthe

first ten frames, which will create the actual

explosion,afterwhichsomeflamesandsmokewillbillowoutwardsfortheremaining40frames.

StartupBlender,ifyou'reupforthechallenge!

DEV.MAG ISSUE 14

(IfyourenewtoBlender,checkoutDev.MagIssue5forthebeginningofourBlendertutorialseries!)(IfyourenewtoBlender,checkoutDev.MagIssue5forthebeginningofourBlendertutorialseries!)(IfyourenewtoBlender,checkoutDev.MagIssue5forthebeginningofourBlendertutorialseries!)(IfyourenewtoBlender,checkoutDev.MagIssue5forthebeginningofourBlendertutorialseries!)

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13


Createamesh'plane'.

Subdividethemeshplane(WKEY)

Selectthefourcornersandscaletheminwards

Go to Edge mode (Ctrl-TABKey) and select

(RMB) the outer edges. I also switched to

wireframeview(ZKEY)foreasierviewing.

Extrudetheedges(EKEY),butpressLMB(left

mousebutton)immediately.Afterpressingthe

LMB,pressSKEY.Thiswillputyouintoscaling

mode.Scaletheedgesoutwards.

Now you haveto change yourviewto aside

view,whichwillallowustoaddtheshapethat

willmaketheparticlesflyoutinawiderarea.

Movetheselectedaxisaccordingtothisimage:

Select the center vertex of the initial mesh

object, and move the vertex so that you an

imageresemblingthis:

TABKEYleaveseditmode.Thisobjectwillbe

theemitterfortheparticles.

It'stimetoaddtheparticlesystem.Ensurethat

ou have enough screen space around the

emitter,sothatyoumayseetheeffectofanyof

thechangesyoumaymake.

ClickontheObjectbutton.

ThenlocatethePhysicsbuttonandactivateit.

Next,createaNEWparticlesystem.

A new menu becomes available. Note that

thereisatabforParticles,aswellasatabfor

ParticleMotion.

Under ParticlesParticlesParticlesParticles, you will find settings that

define the creation and lifespan of particles,

while the Particle MotionParticle MotionParticle MotionParticle Motion tab controls

movementoftheparticles.

Mysuggestionwouldbetosettheparameters

asfollows,afterwhichyoucanstarttweaking:

YouwillnoticethatIonlychangedaboutsixor

sevenparameters.Ifyouwanttheparticlesto

flymorerandomly,tryaddingsomeRandom

undertheVelocityheading.Thesevaluescan

also beadjusted negatively tochange tothe

oppositedirection.

Playyouranimation(mouseoverviewportand

ALT+AKEY),orusethearrowkeystolookat

theanimationoftheparticles.

Nowforthetextureoftheparticles.Thispartisquitechallengingifyouarenewtothis,soallow

sometimetofigurethisout.

TexturingTexturingTexturingTexturing

WewillusethesolidcolorRGBareaforprimary

coloradjustment,and load a texture thatwill

affect the smoky, transparent look ofthe fire

andsmoke.

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14


ClickontheMaterialbutton.

Assignanewmaterialtoyourobject.ClickonAddNew.

Firstly,wewillsetthematerialtocreateaHalo

material. This is used along with particle

systems and can create starry, or smoky

effects.Clickonthehalobutton.Anewsetof

buttons will appear. Set those according to

thesesettings:

Next, we wil l add a texture, and use the

mappingoptionstogetthattexturetoinfluence

thealphachanneloftheparticles.Clickonthe

Texturebutton(that'sthe leopardskinone).Addanewtexture,makeitaCloudstype,and

thensetthesettingsasshownbelow.

Thesizeofourparticles,alongwiththesizeof

thescene,willinfluencewhattheparticleslook

like.Tweaktheparticlesizesettings,aswellas

the noise sett ings (after we've done the

mapping),togetthedesiredeffect.

Transparency(alphachannel)willbebasedon

100%transparent forblack, andfully opaqueforwhite,withshadesofgrayofferingvarious

levelsoftransparency.

ClickbacktotheMaterialsbutton.Youshould

seethemappingoptionstowardstheright-hand

sideofyourscreenifyouhaveadefaultscreen

layout.ActivatetheMapTotab,andactivate

theAlphabutton.ThistellsBlendertousethe

coloursfromthetexturetocalculateanalpha

channel. Don't worry about the pink color

swatch.Weareoverridingthatwiththetexture.

One thing remains to animate the color

parametersontheparticles.Don'tgetconfused

here:

Weaddedatexturetocontroltransparency,not

changetheactualcolouroftheparticles!

(You can see that the Col button is not

activatedintheMapTotab)

We will keyframe the RGB colors using the

IKEY.

EnsurethatyouareonFRAME1.

Again.

Ensure that you are on FRAME 1. You are

goingtostruggleifyouleaveoutthisstep!

Setthecolortoblack,hoverthemouseoverthe

blackswatch, and press the IKEY. Amenu

popsup.ChooseRGB.

Nowadvanceyourframestoframe4.Change

thecolourswatchtoabrightred,andinserta

RGBkeyframe.

Advancetoframe12.Keyframethatsamered

coloragain.

Moveontoframe25,keyframeabrightorange

RGBvalue.

Atframe40,keyframealightgreyRGBvalue.

Last, but not least, use the samemethod to

keyframetwovaluesoftheA(shortfor'Alpha'):

Valueof'1'atframe44;

Valueof'0'atframe70.

You can now set upyourcamera and lights,

and start rendering your sequence. My

suggestionwouldbetorenderPNGfileswith

thealphachannelswitchedon.Youcan then

composite your explosion on top of other

images.?RMAN?RMAN?RMAN?RMAN

DEV.MAG ISSUE 14

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15

GAME MAKER

DESIGN TOOLS OF THE TRADE

fyouaskatriple-Agamedeveloper

what isrequired tocreatea quality

game, hell almost certainly include

atalentedprogrammingteaminhislistof

prerequisites, leaving many a budding

game developer to wallow in sorrow.

Thankfully, a Dutch computer scientist

named Mark Overmars decided that

complexprogrammingneedntbeahurdle

forproducingqualitygames.Hecreated

Game Maker, a true boon to the game

developmentcommunity.

Anyone who ever had even the most

fleeting thoughts about a potentially

interestinggameideawill findhimselfathome with Game Makers simple, yet

powerful, tools. These very tools also

happentobefree.Well,mostofthemat

least.Theprogramcomesoftwoversions:

Theunregistered(Lite)version,whichis

freeof charge,andthe registered (Pro)

version.ThePro version, atthemeager

price of 15 (roughly R150), includes

supportforadvanceddrawingeffectsand

functions,aneffectssystem,andsupport

for.dllimports,amongotherthings.

Game Makers strength lies in its

innovative drag-drop interface, which

allows multiple game creation

opportunitieswithlittleornoprogramming

required. As such, the world of game

developmentisnowopentothosewithout

intimateknowledgeofcomputersystems

andprogramminglanguages.

But before any of you hardcore game

programmers write off this measly

program,knowthat,forthoseinclinedto

delve deeper, Game Maker includes arobust scripting language that will allow

eventhemostcomplexinteractionstobe

created.Thescriptinglanguage,knownas

Game Maker Language or GML,

increases the appeal of Game Maker

beyond the non-programmer crowd.

Togetherwiththescriptinglanguage,high

qualitygamescanbecreated.Remember

TheCleaner,agamewereviewedawhile

back?Youguessedit!Thatwasmadein

GM. As was Ninja loves Pirate. (http://

www.ninjalovespirate.com/)

Game Maker also boasts a huge

community base, providing assistance

and tutorials for anyone eager to learn.

The official Game Maker Community is

likelythelargestofthese,butmanymore

are abound. A previous Dev.Mag issue

(Issue9)includesamoreexhaustivelist.

Sowallownomore.GograbGameMaker

andstartmakinggames.Andonceyoure

done, well be more than eager to seewhatyouvemade.

CHIPPITCHIPPITCHIPPITCHIPPIT

I

DEV.MAG ISSUE 14

GetGameMaker:

www.yoyogames.com/gamemaker

Tutorialsandexamples:

www.gamedotdev.co.za

www.yoyogames.com/make/tutorials

64digits.com/games/index.php?example=1

GameMakerCommunity:

gmc.yoyogames.com

TAKING THE BLUE PILL FOR ...

8/14/2019 Dev.Mag - 14

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Todaysarticlewillcontainthefollowingsections:

1.AbriefGameMakertutorialshowingthebasicsofgettinganobject

tomove,bothwiththekeyboardandwiththemouse.

2.Thisisfollowedbyadiscussion,indetail,ofthevariousGameMak-

eractionsavailabletoyou.

3.GameMakerLanguage(GML)isapowerfulwayforthedeveloper

togetclosertotheaction,andcontainsnumerousfunctionsformov-

ingobjects.

Game Maker Tutorial

Thistutorialisgoingtocreatearoom

thatcontainstwo balls. Thefirstball

willbecontrolledbythearrowkeyson

thekeyboardandthesecondballby

clickingthemouse.

Thistutorialisnotagameassuch,butisdesignedinsteadtoshowvari-

ousmethodsofmakingobjectsmove.Afewsmallchangescouldmakethisintoafungame.Somepossibilitiesmightincludespreadingvarious

objectsaroundthescreenandscoringastheygeteatenbytheballs,

creatingatwoplayerPacMangamewheretheballsmustrushthrough

amaze,ofevenachasinggamewhereoneplayermusttryandcatch

theother.

Step 1 Create sprites

InGameMaker,addanewsprite.Selectanimageforit,suchasoneof

theballsinthedefaultgraphics.Thespritescreenshouldlooklikethe

imageoverthepage:

WelcometothefirstintheBeginnersGuidetoMakingGames.

Eachmonthasingleimportantconceptrequiredformaking

gameswillbediscussedindetail.Thismonthwerestarting

withmovingobjects,andnextmonthwelllookatcollisions.Thesehave

beenchosenasthefirsttwoconceptsbecauseagoodunderstandingof

themwillallowyoutostartbuildingyourownuniquegames.

ThemaingoaloftheBeginnersGuideseriesistotryandensureade-

tailedunderstandingofthevariousconceptssothattheycanbeapplied

toothernewandexcitinggames.Whilemosttraditionaltutorialswillshow

whatcodeisneeded,theseguideswillensurethatyouwalkawayactu-

allyunderstandingeachoftheseconcepts.

Thisarticleisaimedatsomeonewhohasjuststartedlearningtomake

games.Whileitisassumedthatthereaderofthearticlehascomplet-

edthefirstofficialGameMakertutorialandisable,therefore,tocreate

spritesandobjects,itisquitepossibletofollowthearticlewithouthaving

doneso.Thearticleis structurednotonlytointroduceanewprogram-

mertotheconcept,butshouldbeofsomevaluetotheintermediatelevelprogrammeraswell.

Moving an object GM tutorial

Thevastmajorityofgamesrequiremovementwithinthegame.Some

gamessuchaswordpuzzlesgetawaywithoutusingmovingobjectsbut

thesearetheexceptionratherthantherule.Tokeepthingssimple,well

onlylookatmovinganobjectin2Dspace,whilealaterarticlemaylook

ataddingthethirddimension.

DESIGN HELPING YOU ALONG

A BEGINNERS GUIDE TO

MAKING GAMES

DEV.MAG ISSUE 1416

1PART

HINT: When using Game Maker

always set the Advanced option

on. This makes it easier to see and

access all the functions.

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TomovetheobjectonthescreenwenowneedtoclickanddragtheStartmovinginadirectionactionintotheactionslist.Thisisthefirst

actionontheMoveactionscreen.FormoredetailsonhowtheStart

movinginadirectionactionworks,consultthenextsection.

WheneveranactionisaddedtotheActionslist,adialogueboxwillbe

displayedwhereyoucansettheparametersfortheaction.Inthiscase

weclickthearrowpointingleftandsetthespeedto5.(Notethatthis

speedisgoodfortestingthings,butcansometimesbetoofastforactual

in-gameevents).

Step 3 Adding our object to the room

RoomsarewhereeverythinghappensinaGameMakergame.Without

aroom,objectscantdoanything.Roomscanalsobesetuptocontain

prettybackgroundsandcantransitioninfancyways.

Create a new room inGameMaker. On the left tab ensure that the

oBallKeyboardobjectisselectedtobeaddedtotheroom.Ifitisnt,click

ontheselectionboxunderObjecttoaddwithleftmouseandselectit

fromthelist.Clickwiththeleftmousebuttonanywhereintheroom.

Step 4 It works

RunyourgamebypressingthegreenRun

Gamebutton.ThebeautyofGameMakeris

howyourgamerunseverytimewithoutfail.

PresstheLeftarrowkeyandyourballwillgoflyingofftotheleft.Unfor-

tunatelythereisnowayofchangingitsdirectionorstoppingitatthemo-

ment.Tobeablechangethedirectionoftheballrepeatwhatwasdone

abovebutfortheotherthreedirectionsoftheKeyPressevent.

Whilenotimportantforthistutorial,itisoftenagoodideatosettheorigin

ofaspritetothecentreofthespritetoassistwithcollisiondetection.To

dosopresstheCentrebuttonontheSpritescreen.

Transparentspritesusuallylookalotbetterthanasolidspriteunlessfor

somereasonthespriteisasingleblockofcolour.Thecolourusedto

makethespritetransparentisthecolourinthetoprighthandcornerof

thesprite.

Step 2 Making an object

GameMakerusesaspritetostorethegraphicsforthegame,andthe

objectsinthegamearerepresentedbyaGameMakerObject.Createa

newobjectusingthepreviouslycreatedsprite.

Name this object oBallKey-

boardtoshowthatthisballwill

becontrolledbythekeyboard.

To move an object in Game

Maker we need to create

eventsandallocateactionsto

theevents.For thekeyboard

weneedtocreatefourevents

(one for each arrow key di-

rection)and allocatea Start

moving in a direction action

toeach.

OntheobjectscreenselecttheAddEventbutton,andinthefollowing

dialogueboxselectKeyPressandthenchoosetheLeftoptionfromthe

menu.Thiscreatesaneventthatwilloccurwhenevertheplayerofthe

gamepressestheleftarrowkey.


DEV.MAG ISSUE 1417

HINT: Always rename the items you create in

Game Maker. It is always easier to remember

that something called sBall is a sprite contain-

ing the image of a ball than to try and remem-

ber that sprite125 is a 16 frame animated

image of a vampire firing a bazooka!

HINT: A good habit to get

into is saving your game

every time before you run it!

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theydo,andwhatalternateoptionsareavailableforeachthingyouwanttodo.

OfteninGameMakertherearealternateoptionstoachievethesame

thing.Howeverbyunderstandingwhatthevariousoptionsdo,theycan

bebetterusedtoachievetheeffectsthatyourgamerequires.

Movement inactions consists of two ele-

ments, direction and speed. Speed indi-

cateshowfartheobjectwillmoveineach

step, so the higher the speed value, the

fastertheobjectwillmove.Directionshows,

indegrees,thedirectiontheobjectshould

bemovingstartingatzerobeingrightand

movinganti-clockwise.Adirectionof90in-

dicatesadirectiondirectlyup,whileavalue

of180wouldmeandirectlyleft.

Anicetrick tounderstandinGameMakeris the use oftheRelative

checkbox.Whentherelativecheckboxischeckedthevaluesentered

intotheparametersboxesareaddedtothecurrentvalues.Soforex-

ampleifanobjectismovingataspeedof5,andarelativevalueof1is

selectedtheobjectwillstartmovingat6thereafter.

Start moving in a direction

The most basic of the movement

actionsallowsyoutochoosethedi-

rectionyouwanttheobjecttomove

withoutneedingtounderstandwhat

degrees and direction mean. This

action is best used when you are

designinga gamethatusesclearly

definedhorizontalandverticallines,

forexampleamazegame.

Set direction and speed of movement

This option allows you tomove an

object in any direction and at any

speed.Touseitproperlyyouneedto

understandhow thevariousdegree

pointswork.Beingabletosetanydi-

rectionformovementgivesthedevel-

operaverylargerangeofmovement

options.Being able tomovein any

direction is typicallyusedin games

Step 5 Mouse movementMovingobjectsusingthekeyboardisjustonemethodofmovingtheob-

jectonthescreen.Anotherfrequentlyusedmethodofcontrollingobject

movementistousethemouse.Makinganobjectmovetowardthemouse

isinfactveryeasy.

Followthepreviousinstructionstocreateanewsprite(usingadifferent

ballpicture),andanewobjectcalledoBallMouse.

Createaneweventforthenextobject,selecttheMouse,GlobalMouse

EventthentheGlobalLeftPressed.MouseeventsinGameMakercan

applytotheobjectindividuallyoronagloballevel.MouseEventssuchas

Mouse,LeftButtonwillonlyapplyiftheplayerleftclicksontheactual

object.TheGlobalMouseEventswilltriggerfortheobjectirrespective

ofwheretheplayerclicksonthegamescreen.

WhenusingtheGameMakeractions,itispossibletousetheinternal

GameMakerfunctionsasparameters.Inthiscasewewanttomakethe

objectmoveinadirectiontowardthemouse.FortunatelythereisaGame

MakeractioncalledMoveinthedirectionofapoint.Usingtheinternal

GameMakermouseinformation,wecanjustsetthexandycoordinates

tomouse_x andmouse_ywhichrepresent thecurrent positionof themouse.

Addthenewobjectintotheroom.Runthegameagainandclickrandomly

onthescreenandwatchhowyournewballfollowstheclicksaroundthe

screen.

Moving objects with actions

GameMakeriscoolbecauseitseasy,andActionsaresomeofthemost

importantthingsthatmakeGameMakersuchaseasytooltouse.Toget

themostoutoftheGameMakeractions,youneedtounderstandwhat


DEV.MAG ISSUE 1418

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theYtomouse_y.

b.Setthedirectiontopoint_direction(x,y,mouse_x,mouse_y)and

thespeed

Therearealmostalwaysvariousdifferentwaystomakeanobjectmove

thewayyouwantitto.

Moving objects with GML

GameMakeractionsareshortcutstoGameMakerLanguageconstructs.

Whilethatsoundscomplicated,itbasicallymeansthatactionsare the

easierwayofdoingthingsthatcanbedoneinGameMakerLanguage.

Beforewestartdiscussingthevariousoptionsformakingobjectsmove,

hereisaquickbreakdownofhowmovementinGameMakerworks.

Allmovementisbasedonadirectionandaspeed.Eachstep(frame)

makestheobjectmoveanumberofpixelsonthescreenasspecifiedby

thespeedinaspecificdirection.Anotherwayoflookingatthisisthatthe

objectsmoveasetspeedinaverticalandhorizontaldistance.Allthese

valuesarepropertiesoftheobjectandcanbemanipulateddirectly.

PropertyDescriptionhspeed Horizontalcomponentofthespeed.

vspeed Verticalcomponentofthespeed.

directionCurrentdirection(0-360,counter-clockwise,0=totheright).

speed Currentspeed(pixelsperstep).

Nowitsimportanttounderstandthatthesepropertiesadjustbasedon

thevaluesetintheotherproperties.Sosettingthedirectionandspeedof

anobjectalsochangesthehspeedandvspeedoftheobject.

Calling a script

Tocallascriptforanobject,addaneventtotheobjectandaddtheEx-

ecuteapieceofcodeactiontotheactionlist.Inthepopuptexteditor,

addthecommandsyouwanttobeexecuted.

ScriptscancontainanyoftheGameMakerLanguagefunctionsaswell

asvariouscontrolstructuressuchasforloopsandifstatements.GML

allowsstatementstobegroupedtogetherthroughtheuseofbracesto

identifystartandendsections{}.

Rememberalsothatitispossibletoaccesspropertiesofotherobjects.

Soitsquitepossible,forexample.todothingslikemovingtowardother

objectsorusingthepositionofotherobjectstodefinethemovementsof

theobject.

thatuseanopengameenvironment,whereanobjectneedstomovein

anydirectionbetweenpoints,suchasenemyfighterplanesinashooter

game.

Move in a direction to a point

Rather than forcing the game de-

velopertoworkoutthedirectionan

objectwouldneedtomoveintoget

to a point, Game Maker has sup-

plied an action to just define the

point to which an object needs to

move. Internally, this action uses

theobjectscurrentposition andthe

destinationpointtocalculatethedi-

rectiontheobjectneedstomovein.

Moving directlyto a pointis very useful in gameswhere one object

movestowardanothertoattackit,suchasenemybulletsbeingshotat

theplayer.

Set the horizontal speed, set the vertical speed

Theseverysimpleoptionsallowyou

tomoveanobjectinahorizontalorverticalmanneratasetspeed.Note,

however, that these options do not

cancel the other directional speed

that has beenset. Thismeansthat

ifanobjectismovingupthescreen

andaHorizontalSpeedissettheob-

jectwill beginmoving inadiagonal

direction and not just horizontally.

Theseactionsareusefulingamesthatneedsomesortofaccelerationor

decelerationinadirectionoptionratherthanspecificspeedsettings.

Some examples

Here are some examples of doing the same thing inmany different

ways.

1.MovinganObjectLeft

a.Use Start moving in a direction, choose Left and define a

speed

b.UseSetdirectionandspeedofmovement,withadirectionof

180andaspeed.

c.UseMoveinadirectiontoapoint,setthenewpointsXvalue

tox-100andsettherequiredspeed.

2.Movetowardthemouse

a.UseMoveinadirectiontoapoint,settheXtomouse_xand


DEV.MAG ISSUE 1419

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Special moves

GMLcontainssomespecialmovementfunctions.Thevariousjumpfunc-

tionsarebeingexcludedastheywillbecoveredinafuturearticle.This

articlelooksonlyatthefunctionsthataffectthemovementoftheobject.

move_towards_point(x,y,speed)

DoesthesameastheMoveinthedirectionofapointaction.Soina

globalmouseleftpressedeventapieceofscript

move_towards_point(mouse_x,mouse_y,5);

willmovetheobjecttowardsthepositionofthemouse.

The power of scripts

Whileitiscertainlypossibletocreateafunplayablegamewithoutusing

scripts,thepersonusingscriptswillprobablybeabletocreateamore

immersivegameastheywillbeabletoincludeproperAIandmorebe-

lievablebehaviours.TakingthetimetolearntouseGMLwilldefinitely

improveyourgames.

CAIRNSWM

Moving the object

InGMLmovinganobjectinaspecificdirectionisaseasyassettingthe

directionandspeedpropertiesoftheobject.SobycreatingaKeyPress,

Lefteventandexecutingthefollowingcode:

TheobjectwillmovetowardtheleftjustasiftheStartmovinginaDirec-

tionactionwasusedtomoveleftataspeedof5.

Theothermovementactionscansimilarlybedefinedincode.Toswap

thehorizontalorverticalmovementthefollowingstatementcanbeused:

vspeed = -vspeed;

Andtomaketheobjectmoveinexactlytheoppositedirectiontowhichitiscurrentlymoving,try:

Direction = 360 direction;


DEV.MAG ISSUE 1420

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So.RoachToaster2has,asofJune

2007,beenayearintodevelopment

frominitialdesigntobeta.Iamvery

very proud of what I have been able to ac-

complish.Therehavebeenlotsofthingsthat

nabbed myattention fromRoachToaster2 -

school,games,gamedevcompetitionsandjust

lifeingeneral.

AsIamsittinghere,RoachToaster2isready

forpublictesting.Thistestingphaseisbasically

fortestingthefullgameplay.Doesitwork?Is

it fun?The nextphasewill bethemeticulous

balancing/polishingphase.Iwanttohaveafull-

blownfirstbetathrownouteverywhere.Ieven

wanttoflauntittopossiblepublishers.Thebig

thing, however, is that I am stuck without a

properinternetconnection!

Yes,thebanethatisSouthAfricastelecommu-

nicationsdidnotplanwellenough.Theregion

Iliveincurrentlyhasashortageoftelephone

points.Theyareintheprocessofupgradingit.

ThewayIcurrentlyconnecttotheInternetisnot

socosteffective.ItisaboutR2permegabyte!

Withoutmyproperinternetconnection,Iwont

be able to post, read feedback, and uploadupdates without chalking up a considerable

amountintelephonebills.So,duringthishia-

tus, I amdoingfivethingsconcerningRoach

Toasterasawhole.

1)Imgettingtheart/spritesforRoachToaster2

done.Ivealreadygotanawesomemainmenu

pagefromalocalartist.

2)IvealwayswantedtoremakeRoachToaster

1.Thisisbecausepeoplemightwanttoplay

RoachToaster1asanextendeddemoforRT2,

and because ofRoachToaster1s poor pro-

ductionquality,Iamworkingonaremake.This

remakewillbemadeinXNAforacompetition.

DuetoXNAsbadsharingcapabilities,Imight

justportthegraphicstotheGameMakerfilein

theend.

3)Ialreadyhavethegameplayandstoryde-

velopmentinminduptoRoachToaster4,and

Ineedthistimetodevelopacharacterthatwill

appear in the upcoming games. This might

seemodd,butwhenRoachToaster2getsre-

leased youwill knowexactlywhatI meanby

this.

4)Ifyoudontknow,theofficialRoachToaster

website is up! http://www.roachtoaster.com.I

plantorevampthesiteabit,i.e.addpictures/

screenshotseverywhere,andjustprettyitup.

ROACH TOASTER 2: PICKING OUT THE BUGS

PART 5

PROJECTS LEARNING HOW ITS DONE

5)Ialsoplantosortouttheonlinepaymentop-

tions.Ihavenocluehowthisworks,andIhave

signed up for several e-commerce providers

justtogetabetterideaaboutitall.

Myoriginalintentionwastoreleasethebetain

December2006Oh,howwrongIwas!Asyou

cansee,IhavenoideawhenRoachToaster

2willbereadyforrelease.Withthewayithas

developedthus far,Id say(with nocertainty)

it will be finished round aboutOctober 2007

(yes,rathersettoofarintothefuture,thantoo

soon).

For more info onRoach Toaster 2:Big City,

head on to http://www.shotbeakgames.za.net

orthenewsitehttp://www.roachtoaster.com

TROOJG

DEV.MAG ISSUE 1421

( Wondering what were talking about over here? check out Dev.Mag Issue 10 for the beginning of this Project series! )

8/14/2019 Dev.Mag - 14

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(a triangle that contains a single 90 degree

corner). Heres one I found lying around:

Firstly,itsimportantthatwenamethesidesof

thetrianglesothatwecanidentifythemwhen

webuildourequationslater.Intrig,wename

sidesbasedontheirrelationshipstothecorners

ofthetriangle.Takethistriangleasanexample:

Inthis triangle,wevedefinedoneof thenon-

right-angles with the variable theta (). For

now, this issimply a variableto identify the

Trigonometry. The mere mention of it

strikesterror into the minds ofbewil-

deredhighschoolstudents.Confusing

ratios,bizarrediagrams,tryingtofindthesineof

thecosineofthetangentoftheta-manypeople

struggletowraptheirmindsarounditandeventu-

allygiveupindesperationtodosomethingeas-

ier,suchasendingwarorachievingcoldfusion.

Well,despitewhatyour high school teachers

may have said, trigonometry can actually be

useful! Yes, in the vast sea of unintelligible

termsisavaluableandpowerfulmathematical

toolthatcanaidyouimmenselyinthehumble

task of game design. The aim of this series

istoexplaintoyoujusthowsimpletrigonom-

etryreallyis,andhowyoucanuseittosolve

some very common programming problems.

Hopefully itwill make the job of coding your

nextblockbustergamejustthatlittlebiteasier.

First Principles - The Triangle

Before we start writing any trig in our code,

its necessary to understand all the nasty

mathematical stuff behind it (just joking, its

notthatbad!).First,weshould takea lookat

how trigonometry works at the most basic

level. Todo that,well need a triangle. Morespecifically, well needa right-angled triangle

corner dont worry about about how the

numbers fit in just yet! Now that weve de-

fined , we can use it to identify our sides.

Nowwevedesignatedoursides.Intrig,sides

arealwaysdesignatedrelativetotheanglethat

wereworkingwith,inthiscase.oistheside

oppositetothespecifiedangle.a istheangle

adjacent(nextto)thespecifiedangle.h isthe

hypotenuse,whichisalwaysthesideoppositeto

the90degreeangle.Clear?Well,ifnot,letsgo

throughthesameexercisewiththeotherangle

inthetriangle.LetsdesignatethatoneAlpha

(),andtakealookathowthisaffectsoursides.

GAME CODING WITH TRIGONOMETRY

PART 1

TECH WHEN MATH GETS USEFUL

DEV.MAG ISSUE 1422

Figure 1: A boring right-angled triangle

Figure 2: Boring right-angled triangle with

angle theta

Figure 3: RA triangle with angles and sides

defined

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This isall good and fine, but the real magic

comesinwhenweslotnumbersintothosevari-

ables.Timeforsomegoodold-fashionedmaths!

Basic Calculations

Lets take the trianglethatwevebeenwork-

ing on and plug some numbers into it:

Now we have numbers to work with! How-

ever, youll notice that side o and a havent

been givennumbers.We have noideawhat

the lengths of those sides are. That means,

of course, that well have to calculate them!

Calculating anything using trigonometry re-

quiresthreesteps:

1.Determinewhatnumbersyouhave,andwhat

numbersyouwant.

2.Determinewhichratiotouse,andbuildyour

equation.

3.Substitutetheknownvaluesintotheequation

andsolvefortheunknown.

Thatmayseemlikequiteabrainful,butonceyou

seeit inactionyoull appreciateits simplicity!

First, we take a look at what we have:

we have values for (45) and h (6). We

want to calculate o and a. Next, we deter-

Notethatthistriangleisstillthesametriangle.

Wevejustrenamedthesidesaccordingtowhich

cornerwereviewingthemrelativeto,inexactly

thesamewaythatwedidwithangle.Youll

notethathisstillassignedtothesameside.As

Imentioned,thisisbecausethehypotenuseis

alwaysthesideoppositetothe90degreean-

gle,andsowontchangeifweswitchcorners.

Ifthisstillseemsalittleconfusing,dontworry

nextwellbeseeinghowallofthistiestogether!

Trigonometric Ratios

Trigonometry is not a new thing. We owe a

lot of our geometrical knowledge to ancient

Greek mathematicians, such as Pythagoras,

whodedicatedalotoftimetofiguringoutthe

relationships between the sides and angles

of shapes. One of the many things that the

Greeks managed to determine was that the

lengths of the sides of right-angled triangles

weresubjecttocertainratios,extrapolatedrela-

tive totriangles corners intheway thatwas

discussed inthe previoussection.From this,

theyderived commonmathematical functions

touse these ratios for their calculations. For

easeofuse,theygavenamestothesixfunc-

tionsthat theydiscovered.Weknowthemas

sine (sin), cosine (cos), tangent (tan), cotan-

gent(cot),secant(sec),andcosecant(cosec).

Theratiosthatthenamesdescribeareasfollows.

Notethattheaftertherationamesdenotes

whichanglewearetakingthesesidesrelativeto.

mine which ratios we need to use. Gener-ally, we decide that based on the formula

Letscalculateofirst.Wellusehasourknown

value.Asaresult,theabovewilllooklikethis:

Looking familiar? Look back to the table

where I outlinedthe ratios. If you read care-

fully, youll see that the ratio corresponding

too/hissin.Ourequationnowlookslikethis:

Andwhenweplugournumbersinandsolveforo:

Note: You can easily use the Windows cal-

culator in Scientific mode to work with trig

ratios. Simply ensure that the calculator is

set todegrees, thenpunchintheangle (45

inthiscase)and click the sin button toget

theresultabove(0.707).Iveroundedthean-

swer off to three decimals for convenience.

And there you have it! Weve calculated

o to be 4.424 units long! Now try calculat-

ing a (hint: youll be using cos as your ra-

tio - check the list again to see why). You

should get an answer of about 4.243.

What? Out of space already?

Thats all for this month, but despair not!

Next month, well be looking at how to cal-

culate unknown angles, and youll also

get a taste of how you can start using trig

methods in your games. Until then, prac-

tice calculating unknown sides using differ-

entratiosandvalues.Illseeyounextmonth!

GAZZA_N

TECH ELECTRONIC PLAYGROUND

DEV.MAG ISSUE 1423

Figure 4: Right triangle with angle alpha,

and sides

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Impretty sure thatnot many ofyou have

had the pleasure of experiencing the 18

hour non-stop flight between New York

and Johannesburg. For those of you who

havent, re-read the previous sentence and

replacepleasurewithmisfortune,andadd

from hell directly after flight if you would

likehaveanideaastowhatitreallyfeelslike.

Actually, I couldfill anentire separatearticle

justdescribinghowthose18hours feelmore

like3years,andhowInolongerfearwhat

may awaitme inthe afterlife. But I digress...

Looking back on what is nearly eight years

now,thefirstfewmonthsthatI-Imaginespent

ondevelopingwhatwouldeventuallyturninto

Chase:HollywoodStuntDriverwerefilledwith

onegrowingpainafteranother.Therelatively

easypartofthejobhadbeendone,sincewe

had decideduponaconcept togo aboutde-

velopingourfirstgamearound.Nowwewere

atthestagewherewehadtodiginandactu-

ally produce the goods, whichwas not going

tobeaneasytaskgiventhatwehadsucha

small team consisting of only four program-

mers, two artists and a single designer.

Theprogrammingtasksendedupbeingbroken

downquiteeasilywithDavesmaintaskbeingtohandlealloftherigidbodyphysics(forve-

hiclesaswellasdynamicobjects),Mattsmain

taskbeingtocreateplug-intoolsfor3DSMAX

aswellasthevehicleAI,andDansmaintask

beingtherenderingengineaswellasassuming

themantleofLeadProgrammer.Seeingashow

Iwastheleastexperiencedprogrammerinthe

team,Iwasprettymuchlefttohelpoutwher-

everIwasneeded,aswellastotackleallofthe

littlefillertaskssuchastheGUI(whichisntre-

allyafillertaskatall...)andvarioussmalltools.

The art tasks were pretty much divvied up

evenlybetweenHoangandFelixwith bothof

them being equally responsible for level and

objectbuilding,althoughHoangtookonallof

theconceptualartworkcreationaswell.Lastly,

althoughthegamewas very much a design-

by-committee production, it was left up to

Kennytofillinalotoftheblanks,aswellas

to create andmaintainourdesign document.

The rest of1999wasfilledwitha lot ofhard

workfortheteam,butitwasalsoalotoffun.

Ithinkthatweallquiteenjoyedthechallenge

and responsibility of having gone out onour

THE HISTORY OF I-IMAGINE

Part 5: The First 9 Months

HISTORY WHERE IT ALL BEGAN

own tocreatewhatwe hopedwould turnout

tobe a hit game.But before wewould have

the chance to possibly reach that lofty goal,

wewouldhavetonavigatesomeroughseas...

thefirstofwhichwasnotveryfarawayatall.

ThetaleofwhatwouldultimatelybeFelixand

Kennysshort timeat I-Imaginebeganalmost

as soon as they had arrived inSouth Africa.

Unbeknownsttotherestoftheteam,Felixand

Kennyhadabitofaproblem...actuallyitwas

morelikeaddiction,anditwasntlongbeforeit

cametotheforefrontandstartedtocausean

issuebetweenthemandtherestoftheteam.

DEV.MAG ISSUE 1424

( Who? What? Where? If youre lost concerning I-Imagine, check out Dev.Mag Issue 10 for the start of this article series! )

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Theoffendingsubstancewasntalcohol,drugs,

sex,orevenoiledmidgetwrestling.No...itwas

something far more sinister, devious and life

threateningthananyothersubstanceknownto

mankind.AlthoughIamsurethatitwasoriginal-

lychristenedwithadifferentname(whichwasunpronounceablebyhumantongues)inthefi-

ery pits inwhich itwasspawned, tousmere

mortals it was known simply as EverQuest.

I actually shudder when I think back to how

utterly dependant those two poor soulswere

when it came to the sweet, sweet siren call

that beckoned them to her keyboarded bo-

som. Every day around 4pm it was though

the pied piperwouldbegin toplay his magi-

calnotesandFelixandKennywoulddropall

oftheir work,march upto theirrooms, close

theirdoors,and logontowhateverEverCrack

servertheybelongedtoinordertojoinupwith

theirfriendswhohadjustwokenupontheeast

coastofAmerica,onlytoalsobe onceagain

driven to their keyboards by the ever persis-

tentharpysongplayingintheirsubconscious.

Now,asyoucanimagine(frommycompletely

downtoearthandnotdramatisedinanyway

depictionof thecurse thatfollowed Felix and

Kenny from day to day), their actions could

notbuthaveanegativeeffectontheteamand

the work that needed tobedone. Withmost

of theirworking days beingmade upof four

ormaybe five hoursof actual timein frontof

theircomputers, itwas going tobedifficultin

theleast forthem tocontinuealong thispath

andstillremainapartoftheteam.Thismeant

thatDanwasleftwithnochoicebuttositdown

with themand have a long talk. Initially they

responded well, but unfortunately it wasnt

longuntiltheyfellbackinto theiroldpattern.

Danhadyetanothertalkandonceagain,things

gotbetter,butonlyforashorttime.Eventually

Danhadnochoicebuttogivethemanultima-

tum:eithertheyshapeupandbecomeeffective

andcommittedmembersof theteam,or they

wouldhavetopartwayswithus.Imnotsureas

totheirexactreasons(mybeliefisthattheytru-

lymissedalotofthethingsthattheywereused

tofromtheirlivesinAmerica),butinsteadoftry-

ingtoshapeuptheydecidedtoshipout.Felix

actuallycouldntwaittogetbacktotheUS,and

subsequentlyboughtplaneticketsandleftjust

afewdaysafterDansfinalmeetingwiththem,

whichwasaround themiddleof March 2000.

EventhoughFelix andKenny didnt leave us

underthebestofcircumstances,it wasnt as

thoughanyworkdidntgetdoneduringthetime

thattheywerestillapartoftheteam.Infact,

mostofthedemothatweendedupputtingto-

getherforE32000wasdonebeforetheyhad

left.Ourfirst goalwas tohave afunvehicle

simulation up and running with nice arcade-

stylephysics.Weachievedthisbythemiddle

ofJanuaryorsowithourfirstdemo,whichwas

afreeroamingarenafilledwithobstaclessuch

asramps,half-pipes,andloopswhereplayers

wouldtrytoscoreasmanypointsaspossible

by performing rolls, flips, spins, and various

other stunts in a given time limit. We knew

pretty soon thatwe wereonto something as

theentireteamendedupwastingwaytoomany

hoursplaytestingthisdemoonceitwasdone!

Now thatweknewthatwe aphysics system

that would handle the type of gameplay we

wanted ourplayers toexperience,we moved

onto creatinglevels thatwouldshowoff the

core gameplay experience of action packed

stunt driving. Our first level was designed

HISTORY WHERE IT ALL BEGAN

around a post-apocalyptic setting in the vein

of Mad Max, which had the player infiltrat-

ing anenemy compoundto rescue someone

before escaping and having to drive onto a

moving articulated truck. The gameplay here

was almost platformer-like in nature, as we

wanted to try something that hadnt really

beendone withvehicle-based games before.

OurnextlevelwassetinanAsiancitywherethe

player drovea three-wheeled ramen delivery

vehicle.Uponcompletingadelivery,the des-

tinationbuildingwouldexplodeandtheplayer

would have toescape chasing police officers

whothoughtthathewasthecauseoftheexplo-

sion.Thisgameplaywasmorestraightforward

A-to-Bdrivingbutittookplaceinafullypopulated

citycompletewithtraffic.Thecatchthatwehad

withthislevelwasthatthedeliveryvehiclehadanumbrellainthebackofitthatbobbedaround

likeaspringastheplayerdrove,andeveryone

who saw this immediatelywanted todrive it.

SoonenoughthemiddleofMaywasuponus

whichmeantthatitwastimeforE3,soweall

headedtoLAtopitchourgametopublishers.

We rented a small stand in the Kentia Hall,

which for the E3 uninformed was the small-

estofthethreeshow-hallsanditwasusually

hometomuchsmallerdeveloperstryingtoget

lucky. Throughout the show,wemanaged to

DEV.MAG ISSUE 1425

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The topic of Mays devLAN in Johan-

nesburgwasArtificialIntelligence,and

we are very fortunate that we have

DannyDislekciaDaylivingupherewhopro-

videdus with a talk and some advice onthe

subject. Although the speaker was unavoid-

ablylate dueto family matters,Danny never-

thelessgaveagooddefinitionofAIinrelation

togamedevelopmentandabreakdownofthe

phasesorstepswhichanAImustgothroughin

agame,aswellasvarioussystemsavailable

whichthedevelopercanuseto createanAI.

William cairnswm Cairns opened his house

to the local members for the devLAN as he

hadbecome partly immobilised dueto a run-

ning accident inwhich hebroke his leg, and

having the devLAN in his home meant he

didnthaveto travel farand couldparticipate.

The group was quite small this time around

with just 5 ofus, but itstill seemsthe game

developers in Johannesburg are taking their

hobby seriously as half of us had an exist-

ingprojectwhichwewerealreadyworkingon

where we needed some form of dynamic in-

teraction.WewerehopingtousethedevLAN

as the perfect opportunity to get this done.

Danny attested that AI is the art of making

thingshappendynamically,andanAIcanfulfil

multipleroleslikehelpingtheplayermanagehis

resourcesandmaketheworldhesplayingin

morebelievablethanjustbeingabottheplayer

canplayagainst.Wethenexaminedthesteps

anAImusttakewhileoperatingwhichare:In-

formationGathering,InformationWeighingand

Information Output; after which we then ex-

ploredvarioussystemswhichadevelopercould

usetoletthecomputerreachadecision.We

looked atFall-through Logic, State Machines,

Heuristic Systems and Decision Trees and

thevariousbenefitsandcomplexitiesofeach.

ItsnoteworthythatWilliamfinishedasimulator

usingastatemachinewheretheplayerfought

againstotherAIsinagrowyourselforattack

othersscenario.Hisquickgraspofthecon-

ceptsand carefreeattitudeto flashygraphics

meanthefocusedallhisenergyontheproblem

spaceandinthefinaltestingofhisgame,he

hadquitebelievablecharacterstoplayagainst.

Alltoosuddenlytheeveningsetin,andwithother

commitmentstoattendtothemembersquickly

andefficientlybrokecampandheadedhome,

promisingeachothertomeetagainsoonand

TAILPIECE TIME TO CHILL

touploadtheirresultsofthedaysendeavours

whentheprojectsreachedapresentablestate.

I hope we have another devLAN soon as a

lot of work gets done on various projects at

these events and its the perfect time to ask

questionsof other developers, showoff what

youre working on, and learn a little bit more

about the vast field of game development.

FENGOL

To keep up to date about happenings concerning future dev-

LANs, be sure to regularly check up on the Game.Dev website

(www.gamedotdev.co.za) and the Game.Dev forums.

JOHANNESBURG DEVLANGATHERING FOR FUN AND ARTIFICIAL INTELLIGENCE

DEV.MAG ISSUE 1427

Occasionally, a few of the Game.Dev

membersdecidetogettogetherinanon-

Hotlabbykindofwayanddukeitoutwith

somecode.ThedevLANSareaproudex-

ample ofhowlocalgamedevelopersare

able tocombine a chilled attitudewith a

thirstforlearningsomethingnew.Oneof

theattendeesofthelatestsuchgathering

describestheexperience.

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