3D Image Generation - World ATM Congress...Based Rendering § Image Reality v ... § Most...

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3DImageGeneration

Content

§ WhatisanImageGenerator?§ WhatMakesaGoodIG?§ ImageQuality,Pixels&Resolution,FrameRate§ LevelofDetail(LOD),AliasingandAnti-Aliasing,Physically

BasedRendering§ ImageRealityvTrainingReality§ Johnson’sCriteria§ UserControl§ Full3DvPhotoBackdrop§ IGFeaturesandEffects,BasicandAdvanced

WhatisMicroNav?

§ UKbasedspecialistsimulationcompany§ DeliveringATCsimulatorsfor28years§ Delivering3DTowersimulatorswithImageGeneratorsfor

morethan20years

WhoamI?

§ MikeMale§ ExAirTrafficController(Heathrow)§ Co-FounderofMicroNav§ 30plusyearsexperienceinATCsimulation§ Involvedwithmany3Dtowersystems(>20years)§ NotanImageGeneratorexpertbytraining§ Haveseenandexperienceofmany

WhatisanImageGenerator?- IG

§ Wayofpresentingthesimulatedworldin3D§ Mostdevelopmentcamefromflightsimulation- very

expensive,highlycomplex§ Firstexperience- 1994,E&SEP1000- Cost>US$1m§ NowmostlyPCbasedusinggamingtechnology§ Flightsimulationmarket

ú SomenowPCbasedIGsú IGshavetobecertifiedú Stillexpensivebutlessthanbefore

§ ATCcurrentlynotregulatedú Muchlowercostú Abletotakeadvantageof‘games’development

MicroNav andIGs

§ HavebeendeliveringATCtowers(upto360degrees)sinceearly90s

§ UsedseveralIGmanufacturers(includingE&S)§ NowuseImagineSARL

ú TheleadingedgecompanydevelopingATCspecificfeatures

§ PartoftheQuadrantGroup§ Ownsandoperatesfullflight

simulators§ Alsomovesflightsimulators

aroundtheworld

WhatMakesaGoodIG?

§ Severalfactors:ú ImageQualityú ImageFrameRateú Power(inATCterms=theabilitytoshowtherequiredimagewith

enoughmovingmodels)ú Nostutteringú Features

Effectsthatcanbeused Flexibilityofview

§ Allneedtobeviewedinthecontextofthescenariocomplexity

§ Requirementswilldifferfromusetouse

Channels&Synchronisation

§ Achannelisnormallytheimageforasinglescreenorprojector

§ Normallyeachsimulatorwillincludeseveralchannels§ Availabilityoflowcostprojectoranddisplaysystemscan

resultinsignificantnumbersofchannels§ IGmust beabletosupporthighnumbersofchannels§ Allchannelsmusthavesomeformofsynchronisationto

ensurecoherentimagebetweenchannels

ImageQuality

Dubai 3D Model – created by Micro Nav Fast Airport Builder – displayed using Imagine IG

Pixels&Resolution

§ Nosubstituteforpixelsú Seethe4kimageontheMicroNav stand[542]!

§ Essentially,themorepixelsthereare,thebettertheimage

§ Limitedbythedisplaysystem§ Humaneyesaidtobe“equivalentto8kx8k”§ Thereforenoimageasgoodas‘reality’§ Thedownsidetopixels…

ú ThemoretherearethehardertheIGisworkingú Affectstheframerate

FrameRate

§ Thisreferstohowoftenthescreenimageisupdated§ Cinemastandardis24framespersecond(fps)§ IGsgenerallyhavevariablerate– normallyrelatedtothe

displayscreenrefresh.ú Forexamplefor60Hz,frameratessupportedwouldbe:

60fps- 1screenupdateperframe 30fps- 2screenupdatesperframe 20fps– 3screenupdatesperframe…

§ ForATC,30fpsorhigherconsidered‘flickerfree’§ Constantframerateisimportant§ Themorecomplexthescene(scenecontent,pixel

count…)thehardertheIGisworking

SceneContent

§ Sceneconsistsofstaticandmovingmodels(althoughthewholescenecanmove– asinflightsimulator)

§ 3Dmodelsnormallydefinedbyameshcontainingtrianglesofcolourortexture

§ Generally,themoretriangles,thehardertheIGworks

§ Texturesarepatternsthatcanbeappliedtoatriangleratherthansolidcolour

TowerView

§ Staticmodelistheairportscene- trianglecountisfixedforthatelement

§ Notnecessarilyevenlyspreadoverchannels§ Movingmodeltrianglecountwillvarywithtrafficcount

perchannel§ Frameratecanbeaffectedbydynamicscenecontent

(numberofmodels,numberoftriangles)§ Frameratealsoaffectedbyothereffects(weather,fire,

smoke,explosions…)

AircraftorVehicleView

§ IftheIGcanshowtheviewfromtheaircraft(aflightsimulatororATCsimulatorwithpilotview):ú Staticmodeltrianglecountvarieswithlocationanddirectionú Movingmodelsinviewalsoaffectstrianglecountú Visualeffectsalsoaffectsframerate

§ Dynamicterrain(staticobjectterrain)wherepresenthelpsú Shownashigherdefinitionnearaircraftorvehicleú Lowerdefinitionfurtherawayú Maximisesviewqualityandframerate

FrameRateControl

§ WhereIGcannotmaintaindesiredframerate,either:ú Reduceframerateú Reducescenecontent(triangles)

§ Flightsimulatorsmust maintainframeratetoremainfitforpurpose– somustreducesceneú Referredtoasa“deterministic”IGifitreducesscenecontentú Doesthisbyprogressivelysimplifyingmodels(wheremodelsare

createdspecificallyforthatpurpose)ú ReducesLevelofDetail– thingschange/disappear

§ ATCcantoleratesomereductioninframerateú Frameratecanbeallowedtoreduceasneededú Levelofdetailcanbeadjustedtokeepframerate– butthings

mustnot disappear

LevelofDetail(LoD)

§ Techniqueforminimisingtrianglecount§ Detailedmodelsrequiredfor‘closeup’viewing§ Lessdetailedmodelsrequiredfordistantviewing§ PrimarilyappliedtomovingmodelsforATC§ Oftenappliedtostaticmodelsforflightsimulation(to

allowframeratetobemaintained)§ Systemselectstheappropriatemodelfortheviewing

distance

LevelofDetail- Examples

§ Theimagesbeloware3ofthe4LoDs fortheBoeing737-900modelfromtheMicroNav library– notedecreasingquality

LevelofDetail- Implementation

§ RangeforeachLoD defined§ Appropriateimageshowndependinguponmodel

distancefromeyepoint§ UsefulifLoD rangecanbeadjustedbyuser§ LoD rangecanbeautomaticallyadjustedbyIGto

maintainframerate(someIGs)§ Normally3ormoreLoDs available(Imagineuses4)

Aliasing

§ ‘Step’effectofconvertingastraightlineinto‘raster’linesonascreen- observedattheedgesofobjectsandtriangles

§ Ahorizontalstraightlineinpixelslookslikethis

§ Anon-horizontalstraightlinecanlooklikethis

§ Orthis

§ Ifnottreatedmovingstraightlineimageelements(suchaswings)canappearto‘flap’or‘creep’astheymove

Anti-Aliasing

§ Techniquetosmooththealiaseffectbyadjustingthecolourofadjacentpixels

§ Takespower– notusuallyaproblemwithmodernIGs§ Bigsubject– notenoughtime- butasanexample…

PhysicallyBasedRendering

§ Allowsdifferingsmoothnessandreflectivitytobeappliedtoelementsofmovingmodels

§ Givesvaryingreflectivitybetweentheglossyandmattpartsofeachmodel- Addssignificantlytorealism

ImageRealityvTrainingReality

§ IGsstrivetogivemoreandmorerealisticimages§ FunctionslikeAnti-Aliasingcreateimprovedlooking

imagesbuthavedownsides§ Limitedresolutionalsohasdownsideswhencompared

withhumaneye§ Rangesofrecognitionandobservationcanbeaffected§ Needtoolstohelp– forexampleaircraftmodelscanbe

scaledtobeprogressivelylarger§ Thus‘unrealistic’scalecanproduce‘realistic’training

benefit§ Importantthatthisiscontrolledbytheuser

Johnson’sCriteria

§ Commonlyusedtocalculatetherangeatwhichanobjectcanbe:ú Detectedú Oriented(i.e.orientationcanbedetermined)ú Recognisedú Identified

§ Baseduponthecapabilitiesofthedisplaysystemintermsof‘opticallinepairs’(linesofpixels)

§ Oftenusedwhendescribingdisplaysystemcapabilities§ Usecarefully– allsuchfactorsdoalsodependuponthe

qualityoftheimageandthedisplayelements(suchascontrast)

UserControls

§ IGshouldallowusercontroloverallelementsincluding:ú Scene– toolslikeMicroNav’s FastAirportBuilderorImagine

SceneEditorallowuserstocreateoreditairportscenesú Qualityandcontentofmovingmodels

usershouldbeabletocreatemodelseasilytoensuremodels‘fitforpurpose’(nottoodetailedtoaddunnecessarytrianglesbutgoodenoughtoberecognisable)

ú ControloverLoDsú Controlovervisualeffects(suchassizeoffire,sizeandcolourof

smoke)– mustbe‘recognisable’fortheobserverú Controlovermodelscalingú ControloverAnti-aliasing

Full3DScenevPhotoBackdrop/Billboarding

§ Static3Dsceneelementscanbecreatedintwoways§ Full3Dmodelmeansthatallobjectsarefullymodelled§ Scenecanalsobemodelledusingaphotobackdrop– like

a“movieset”– referredtoa‘billboarding’

§ Phototakenofbackgroundthen‘applied’toabillboard

AdvantagesandDisadvantages

§ Full3Dmodelú Potentiallymorecomplextomodelú ThisisresolvedbytoolslikeFABwhichautomaticallycreates‘terrain’

fromdigitalelevationdataandsatelliteimageryú Usereyepointcanmoveanywhereinthesceneú Piloteyepointpossible

§ Billboardingú Reasonablysimpletocreate(althoughneedssomeexperience)ú Aircraftwillbe‘occluded’onlybehindtheflatimageú Usereyepointisrestricted– canmovealittlebutnotfarfrom

‘centre’ú Piloteyepointisrestrictedú UseslessIGpower

§ HaveusedIGswithboth- Billboarding toorestrictive

3DFeaturesandVisualEffects

§ AllIGssupporteffectsthatmodifythedisplayedimage§ Somehavemoreeffectsthanothers§ Someeffectsshouldbe commontoall§ OthersvaryfromIGtoIG§ Essentialeffectswillvaryaccordingtotherequirements

oftheuser§ AlleffectslistedandshownsupportedbyMicroNav and

Imagine

Basic/EssentialEffects

§ AllIGsmust supportthefollowingforATCsimulation:ú TowerViewpointú Day,Dusk,Night,Dawn(withsmoothtransitions)ú ReducedVisibility(mist,fog)ú AirfieldLighting(approach,taxiway)ú VolumetricCloud(withvaryingtypes)ú Precipitation(rain,snow,sleet,hail)ú Shadowsú AircraftLandinggear(up,down)ú AircraftLighting(navigation,strobe,logo,cabin,taxi,landing)ú FireandSmokeassociatedwithaircraftú Representationofmovingpropellerorrotorú Binocularview

Shadows

§ Shadowsareessentialfor‘fixing’theaircraftinthescene§ Withoutshadowsaircraftappeartofloat§ Ideallyshadowsshouldworkwitha‘sunandsky’model

toallowshadowstoberealisticallyshown§ Examplesbelowshowmiddayandlateafternoon

shadows

OtherEffects- Lighting

§ Essentialairfieldlightingelementsincludeapproach,runwayandtaxiwaylights

§ Truepoollightingaddsrealismtoairfieldandmovingmodels

FollowtheGreensCapability

§ Taxiwaylightingcanbedefinedasindividuallycontrolledgroupsandsections

§ RequiredforFollowtheGreenslevelfunctionality§ Needsintelligencebetweensimulator,IGandlighting

control

Trees– Minimum

§ Treesarecommonlymodelledas‘stamps’(flatimagessimilartobillboards)

§ Thesecan‘turn’toremainperpendiculartotheviewer

RealisticTrees

§ More‘modern’treesaretrue3Dtrees§ Withmultiplelevelsofdetail§ Usercan‘zoomin’onthedetail§ Evenaffectedbywind!

Fire&Smoke

Shown in Imagine Aircraft Editor – allows control over location, size, colour, speed etc. of fire, smoke, explosion, gear…

MoreAdvancedEffects

§ Examplesofsomeoftheotherfeaturesthatcouldaddtosimulation

§ AllareavailableusingImagine

FlocksofBirds

§ Ideallywithanimation§ Shouldbecontrollable,ongroundandintheair

Explosions

Shown in Imagine Aircraft Editor – allows control over location, size, colour, speed etc. of explosion and other effects (fire, smoke, gear…)

ThunderClouds

§ IndividualCumulo Nimbus(cb)cloudú Withassociatedlightning(sheetorfork)ú Withassociatedsound

EscapeChutes

SnowAccumulationandClearance

§ Snowaccumulatesasprecipitationobserved- canbeclearedwithsnowclearancevehicle– noterealisticpoollighting

§ Snowre-accumulatesaftervehiclehaspassed

DispensingFireAppliance

§ Withcannoncontrolledfromsimulator

WaterEffects– Ripples&Reflections

RemoteTowerSimulation

§ Inordertosimulatearemotetower,anIGneedssomeadditionalfunctionality:ú InfraRedsimulationú Presentationoflabels

OtherEffectsGeneral- 1

§ DynamicViewpoint– abilitytomovetheeyepointorputeyepointwithintargetaircraftorvehicle

§ SunandSkymodel§ GroundFog(lowlevelfog,inadditiontogeneralvisibility)§ FogBank(withdefinedvolumeandmovement)§ Sandstorm(alsowithdefinedvolumeandmovement)

§ Windsocksandwindblownobjects§ Flares(fromtowerorvehicle)§ AnimatedAirBridges§ Animatedarresternets,jetbarriers,arrestercables

§ FireandSmoke– fromstaticsource§ Characters§ Aircraftandvehiclelabels§ Aircrafttracks§ Visualrepresentationofglideslopes

AdvancedEffects– AircraftandVehicles

§ Animatedaircraftlandinggear§ Animatedtrafficonroads(animatedsplines)§ Collisiondetection§ ArresterHook,DragChute

Conclusion

§ IGsvaryinqualityandperformance§ IGrequirementsmustbeappropriateforscenario§ Featuresrequiredalsospecifiedappropriately§ IGanddisplaysystemmustbeconsideredtogether

§ Thankyou

Questions?

Comeandseeusstand542www.micronav.co.uk

3D Image Generation - World ATM Congress...Based Rendering § Image Reality v ... § Most...

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