© IJIGS/Uni e si y o Wol e hamp on/EUROSIS
REPRESENTING RANDOM TERRAIN ON RESOURCE LIMITED DEVICES
DAMIEN MARSHALL
φ
, DECLAN DELANEY
φ
, SEAMUS MCLOONE*, TOMAS WARD*
φ
Depa men o Compu e Science,
NUI Maynoo h
Maynoo h, Co. Kilda e
E-mail: [email protected]
* Depa men o Elec onic Enginee ing
NUI Maynoo h,
Maynoo h, Co. Kilda e
E-mail: omas.w[email p o ec ed]y.ie
KEYWORDS
Random Te ain, Pe lin Noise, Mobile De ices, Game Boy
Ad ance
ABSTRACT
Random e ain gene a ion is he p ocedu al c ea ion o a se
o da a ha ep esen s closely a belie able landscape.
Common echniques o achie ing his include he use o
ac als and noise. Such echniques usually equi e a la ge
olume o memo y, as he geome y o he e ain needs o be
calcula ed and s o ed a un ime. Gi en he limi ed memo y
a ailable on mobile de ices, such as mobile elephones, he
s o age o he da a equi ed o ep esen massi e e ains can
be di icul . In his pape , we p opose a no el me hod o
s o ing e ain da a on de ices wi h limi ed memo y. This
me hod in ol es placing p e-compu ed blocks o e ain,
known as e ain iles, oge he in a psuedo- andom manne
as go e ned by a noise unc ion known as Pe lin noise. This
allows la ge amoun s o e ain da a o be ep esen ed while
s ill gi ing he appea ance o a andomly gene a ed e ain.
T adi ionally, Pe lin noise is used in he p ocedu al
gene a ion o ex u es and he modeling o na u ally
occu ing phenomena. Using Pe lin noise, only a subse o
he o e all da a gene a ed by he unc ion needs o be s o ed
a any one ime. The app oach ou lined in his pape
associa es a ile o e ain wi h each alue gene a ed by he
Pe lin Noise unc ion, meaning ha only a subsec ion o he
o al e ain is s o ed in memo y a any one ime. We show
how his p ocess can be execu ed in eal ime on a esou ce
limi ed de ice known as he Game Boy Ad ance, and also
illus a e a signi ican educ ion in he memo y equi emen s
o e ain s o age when compa ed wi h adi ional me hods.
INTRODUCTION
A andom e ain is a g oup o p ocedu ally calcula ed alues
ha ep esen s closely a belie able landscape. They a e
u ilised in all a eas o compu e science, especially compu e
g aphics and games (Picko e 1995), whe e hey allow o
he c ea ion o game con en wi h minimal ime o e head.
Also, as e ain maps can be qui e la ge, echniques o
gene a ing andom e ain, such as ac als (Dudgeon and
Gopalak ishnan 1996), and models o na u ally occu ing
phenomena (Kelley e al. 1988), help o minimise ixed
s o age equi emen s. Howe e , his means ha such
me hods usually equi e a oluminous amoun o Random
Access Memo y (RAM).
Wi h ecen ad ances in p ocessing powe , compu e games
a e becoming mo e popula on handheld de ices (Ri e n e
al. 2003). Howe e , he e a e s ill limi a ions o he amoun
o a ailable RAM o such de ices, so ha he c ea ion o
andomly gene a ed e ain o compu e games on such
de ices can be p oblema ic.
In his pape , a no el me hod based on he use o e ain iles
and a pseudo andom noise known as Pe lin Noise is
desc ibed (Rabino ich and Go sman 1997; Pe lin 2002)
T adi ionally, Pe lin noise is used in he gene a ion o
p ocedu al ex u es and he modeling o na u ally occu ing
phenomena such as clouds and smoke (Ye and Lewis 1999;
Hol kämpe 2003) – see Figu e 7. He e, we p opose an
app oach ha associa es a ile o e ain wi h each Pe lin
noise alue. A e ain ile desc ibes a squa e block o e ain
da a. Using Pe lin noise, only a subse o he o e all da a
gene a ed by he unc ion needs o be s o ed a any one ime.
The e o e, la ge e ain maps can be ep esen ed in eal ime
wi h a small memo y oo p in , as only he e ain iles o
in e es o he use a e s o ed a any gi en ime.
The p oposed me hod is implemen ed on a limi ed de ice
known as a Game Boy Ad ance (www.nin endo.com), and
esul s a e p esen ed o he implemen a ion We show ha
signi ican sa ing can be made in e ms o memo y space
equi ed when compa ed o adi ional me hods o s o ing
and ep esen ing e ain. As his me hod makes no use o
loa ing poin a i hme ic i is e y e icien , making i sui able
o use on a wide a ie y o de ices whe e no dedica ed
loa ing-poin uni is a ailable. I would be pa icula ly
sui able o mobile elephones, as i allows o he gene a ion
o massi e e ain maps wi h a minimal o e he ai
download. This is o signi ican impo ance as la ge
downloads ha e been iden i ied as a limi ing ac o in he
nex gene a ion o h ee-dimensional games on mobile
elephones (EDGE Magazine 2004).
The es o he pape is laid ou as ollows. The nex sec ion
in oduces Pe lin Noise and ou lines he sui abili y o he
Game Boy Ad ance as a es bed. The Implemen a ion
sec ion de ails he ealisa ion o he p oposed me hod,
ollowed by a selec ion o pe o mance alues in he Resul s
sec ion. Finally, he pape concludes wi h sugges ions o
u u e wo k.
BACKGROUND
Pe lin Noise
Pe lin noise is one o he mo e impo an noise unc ions
(Pe lin 2002). C ea ed by Ken Pe lin, his noise has he
special p ope y o appea ing andom o he pe cei e , ye
© IJIGS/Uni e si y o Wol e hamp on/EUROSIS
emaining en i ely con ollable. I wo ks by de ining a
numbe o key poin s a se dis ances apa , and de ining he
alues o he in e media e poin s p ocedu ally using
in e pola ion. Any subsec ion o he da a c ea ed by he
Pe lin noise unc ion can be econs uc ed, wi hou he need
o s o e and gene a e he en i e da a se . In his sense, Pe lin
noise can be conside ed o be quasi- andom noise. Fu he
de ail ega ding an implemen a ion o Pe lin Noise is gi en
in he Implemen a ion sec ion.
Game Boy Ad ance
Released in 2001, he Game Boy Ad ance (GBA) is he
successo o he mul i-million selling Game Boy and Game
Boy Colo . The mos impo an speci ica ions o he Game
Boy Ad ance a e de ailed in Table 1.
F om Table 1, i can be seen ha he GBA is e y limi ed in
e ms o p ocessing powe and a ailable Random Access
Memo y (RAM). Coupled wi h he ease o p og amming o
he sys em, his makes he GBA a pe ec pla o m on which
o es ou implemen a ion.
In he nex sec ion, he implemen a ion de ails o he
p oposed me hod a e desc ibed, and example sc eensho s o
he applica ion in ac ion on he GBA a e gi en.
IMPLEMENTATION
In his sec ion, he me hod by which massi e e ains can be
cons uc ed wi h a minimal memo y oo p in is discussed.
The means by which he e ain da a is ende ed o sc een a
a s able ame a e on he GBA is also in oduced.
Pe lin Noise Map o Te ain Tiles
The basis o he echnique desc ibed he e is wha is known as
a e ain ile. A ile desc ibes a squa e block o e ain.
Te ain iles a e used ex ensi ely in many popula game
engines such as To que (Ma shall e al. 2004). Each ile is
ypically de ined by wo g oups o da a – a heigh map,
which de ails he geome y o he e ain, and a ex u e map,
which de ails he colou s and shading o he e ain
(Rabino ich and Go sman 1997). Figu e 1 (a) and (b) de ails
examples o bo h ca ego y o maps. Bo h images in Figu e 1
we e c ea ed using he Wilbu andom e ain gene a ion
applica ion (Slay on 2001).
By placing hese iles oge he in a andom o de , a la ge a ea
o e ain can be de ined – see Figu e 2(a). Howe e , as he
ile size dec eases, he s o age cos o he o de o he iles
can become expensi e, and can e en ually begin o app oach
ha o he adi ional me hod o s o ing each heigh o e ain
in an a ay – see Figu e 2 (b) and (c). This can make such an
app oach unsui able o a limi ed memo y de ice.
This p oblem can be alle ia ed using Pe lin noise o go e n
he placemen o iles. As men ioned in he p e ious sec ion,
any subsec ion o he da a gene a ed by a Pe lin noise
unc ion can be ec ea ed gi en he same inpu alues,
wi hou he need o s o e he comple e da a se gene a ed by
he unc ion. The e o e, only he sec ion o da a o in e es o
he iewe needs o be calcula ed and s o ed a any one ime,
and i is gua an eed ha o he subsec ions o he da a will be
gene a ed consis en ly wi h he same alues.
The main ene o he app oach ou lined in his pape is ha
by de ining a numbe o iles wi h small dimensions, and
associa ing each alue gene a ed by he Pe lin noise unc ion
wi h a e ain ile, hen only he small po ion o a massi e
e ain map needs o gene a ed and s o ed a any one ime,
hus p o iding d ama ic sa ing in e ms o compu a ion ime
and memo y - see Figu e 3. In Figu e 3, each ile is
ep esen ed by a di e en shade o g ay. As he use mo es
abou he la ge e ain map, he subse o e ain ile da a is
epopula ed o ep esen he use s immedia e en i onmen .
Pe lin Noise Implemen a ion
The i s aspec o he app oach explained in his pape is he
manne by which he Pe lin noise map o e ain alues is
gene a ed. The p ima y s ep o his p ocess is he de ini ion
o a g id ha de ines he o e all layou o he map. Each
alue in his g id is known as a e ain s uc u e alue. These
e ain s uc u e alues a e simply andom numbe s, and a e
no ela ed o any pa icula e ain ile. Ra he , hey a e used
in conjunc ion wi h adjacen e ain s uc u e alues in o de
o de ine in e media e e ain ile alues p ocedu ally. Each
P ocesso 16Mhz
Memo y 384 kiloby es
Sc een Resolu ion 240 * 160 pixels
A ailable Colou s 32,768
Figu e 2 (a) Fou 128*128 il
es (b) Eigh 64 *64 iles. (c) Six y ou
32 * 32 iles. A dec ease in ile size inc eases de ail, bu leads o an
inc ease in memo y equi emen s.
Figu e 1 (a) Tex u e map (b) G ayscale Heigh Map.
(a)
(b)
Table 1 Impo an speci ica ions o he GBA
Figu e 3 Only a small subse o all he ile alues is s o ed a any one
ime using a Pe lin noise unc ion. This is epopula ed as he use
mo es abou he e ain.
Full map o e ain
alues gene a ed
using Pe lin Noise
Only a subse o all he
e ain alues is s o ed
a any one ime.
(a)
(b)
(c)
Te ain iles
a e placed in
a andom
o de
Te ain iles
© IJIGS/Uni e si y o Wol e hamp on/EUROSIS
o hese e ain ile alues is a e e ence o a pa icula e ain
ile. Al hough his g id o e ain s uc u e alues will ha e
iny dimensions, i can be hough o as being i ually la ge,
as each elemen ep esen s a poin along a la ge map – see
Figu e 4. So, o example, a 4 * 4 a ay, wi h a i ual
dis ance o 1024 pixels be ween elemen s o he a ay,
ep esen s a 4096 * 4096 pixel e ain map.
Nex , he e ain s uc u e alues a e used o p ocedu ally
de ine he in e media e e ain ile e e ences ha desc ibe
he e ain immedia ely su ounding he use .
Fi s ly, he a ea wi hin he g id o e ain s uc u e alues ha
cu en ly houses he use is loca ed, and he poin s ha de ine
he bounda ies o ha a ea a e eco ded. So, aking he
example om abo e, i he playe was a poin (1056,3042)
on a 4*4 map wi h a i ual dis ance o 1024 pixels be ween
each elemen , hen he playe would be loca ed be ween he
e ain s uc u e elemen s (1,2), (1,3), (2,2) and (2,3), as
de ailed in Figu e 5 below.
By linea ly in e pola ing be ween he wo op and he wo
bo om bounding alues using he playe ’s ho izon al
posi ion, and in e pola ing be ween he esul s o hese
ope a ions using he playe ’s e ical posi ion, a alue which
ep esen s he ile in which he use esides can be de ined –
see Figu e 6.
Map o Te ain Tiles
T adi ionally, he alue gene a ed by his p ocess would be
used in conjunc ion wi h o he gene a ed alues in o de o
ep esen a ex u e o na u ally occu ing phenomena
p ocedu ally, as in Figu e 7.
Howe e , o his implemen a ion, each alue is ac ually a
e e ence o a pa icula e ain ile. As he e will be only a
limi ed numbe o e ain iles, and he gene a ed alue may
exceed he o al numbe o e ain iles, he esul may ha e
o be scaled. This can be achie ed using a simple modulus
ope a ion.
This p ocess is epea ed using he coo dina es su ounding
he playe . The numbe o epe i ions equi ed will a y,
depending on he size o each indi idual ile and he o e all
map size equi ed. This esul s in a empo a y a ay o da a
con aining e e ences o he e ain iles ha immedia ely
su ound he use . An example o such an a ay is gi en in
Figu e 8. Fo cla i y, each sepa a e map is ep esen ed by a
di e en shade o g ay. Each colou ep esen s a map simila
o ha in Figu e 1(a).
Howe e , as can be seen in Figu e 8, h ough he use o his
me hod alone, a se ies o dis inc pa e ns can be obse ed in
he placemen o e ain iles. Such pa e ns a e exac ly wha
Pe lin noise is celeb a ed o . Howe e , in he echnique
unde discussion, mo e andomness is desi ed o gene a e
uly andom landscapes. This is achie ed ia he use o
ano he a ay o andom alues, which is popula ed along
wi h he e ain s uc u e g id. The alue acqui ed by he
in e pola ion p ocess is used o index in o his andom a ay,
allowing o ano he laye o andomness, wi h li le
compu a ion o e head. An example o he empo a y a ay o
e ain ile alues p oduced using his me hod is gi en in
Figu e 9. Again, o cla i y, each sepa a e map is ep esen ed
by a di e en shade o g ay.
Vi ual dis ance
be ween e ain
s uc u e alues
Bounding
Values
Random Te ain S uc u e
Value
Bounding Values
Playe Posi ion
Vi ual dis ance
be ween g id
alues
0
Te ain s uc u e
alues
Figu e 4 A g id o e ain s uc u e alues de ines he o e all layou
o he e ain. In e media e alues a e calcula ed p ocedu ally.
Figu e 9 No disce nable pa e ns appea when a andom numbe
look-up able is u ilised
Posi ion o playe
wi hin he e ain
Te ain iles
su ounding he
playe . No
pa e ns occu
wi h usage o
andom a ay.
Random Te ain S uc u e
Value
Bounding Values
Playe Posi ion
Te ain iles
su ounding he
playe . Dis inc
pa e ns can
eme ge.
Posi ion o playe
wi hin he e ain
Figu e 8 Only he e ain iles ha immedia ely su ound he playe
a e calcula ed. The playe is loca ed a he cen e o hese iles.
In e pola ion
Poin
S ep 1: In e pola e
be ween op and
bo om alues.
S ep 2: In e pola e
be ween esul s o
S ep 1 abo e.
Figu e 6
Resol ing he e ain ile alue based on he playe s
posi ion and he calcula ed bounding alues.
Playe Posi ion
Full map o
e ain alues
In e media e e ain ile
alues a e calcula ed
p ocedu ally
Figu e 5 Loca ion o a playe ’s posi ion wi hin he e ain s uc u e
g id.
1
2
3
Figu e 7 An example o a adi ional ou pu om he Pe lin noise
unc ion
1
2
3
© IJIGS/Uni e si y o Wol e hamp on/EUROSIS
This empo a y a ay ep esen s only a small subsec ion o
he o e all e ain da a. Howe e , his ac is no no iceable
o he use , as he empo a y a ay o e ain ile e e ences is
epopula ed when he playe eaches a ce ain dis ance om
he pe ime e o he map. This a ay is hen used as inpu o
he ende ing p ocess.
Rende ing P ocess
The ende ing p ocess uses a me hod known as ay-cas ing
and oxels in o de o d aw he ele an e ain iles o he
sc een in a imely ashion (K eege e al. 1998; S einbach e
al. 2000). Al hough his me hod has i s limi a ions, such as
only wo planes o mo emen , i allows o a pseudo h ee-
dimensional e ec on esou ce-limi ed ha dwa e such he
GBA, a a s able ame- a e. Figu e 10 de ails sc eensho s o
he ende ing applica ion in ac ion on he GBA.
Supe imposed on he images is a g id de ining he
bounda ies o each e ain ile. Figu e 10 also ein o ces he
ela ionship be ween e ain iles, as seen in Figu e 1 (a) and
(b), and he empo a y a ay o ile e e ences as seen in
Figu e 8 and 9.
RESULTS
Compu a ion Time
As a p elimina y exe cise, he compu a ion ime equi ed o
calcula e he empo a y a ay o e ain iles su ounding he
playe was eco ded. This is achie ed by using an in-buil
ime on he GBA ha is inc emen ed on e e y clock ick. A
unning a e age o he amoun o ime in milliseconds aken
o popula e he ile map is no ed. In each case, he ile map
equi ed was 1024 * 1024 pixels. The es e na iga ed he
en i onmen o 60 seconds, and a he end o his ime, he
a e age compu a ion ime was eco ded. The esul s o his
expe imen a e p esen ed in Table 2.
As can be seen om Table 2, he compu a ion ime equi ed
is minimal, and can be calcula ed in eal ime on he GBA.
As no loa ing-poin a i hme ic is used in he calcula ion o
he e ain ile alues, his p ocess is sui able o a wide ange
o de ices whe e no ha dwa e suppo o loa ing poin
alues is a ailable. To u he demons a e he e iciency o
his app oach, he compu a ion ime equi ed o he c ea ion
o a comple ely new andom map was also in es iga ed. In
each case, andom maps we e gene a ed o 60 seconds, and
a unning a e age o he compu a ion ime was eco ded
using he in-buil GBA ime s. As his p ocess simply
in ol es he egene a ion o he e ain s uc u e g id, he
compu a ion ime equi ed is minimal, as de ailed in Table 3.
Tile Size Tiles equi ed Time
128 * 128 pixels 8 * 8 iles <1 ms
64 * 64 pixels 16 * 16 iles 10 ms
32 * 32 pixels 32 * 32 iles 67 ms
16 * 16 pixels 64 * 64 iles 165 ms
Te ain S uc u e g id dimension Time
4 * 4 g id elemen s 1. 25µs
8 * 8 g id elemen s 3.5µs
12 * 12 g id elemen s 6.625 µs
16 * 16 g id elemen s 16.5µs
Memo y Usage
The mos c i ical aspec o implemen ing he p oposed
echnique in mobile de ices is how i exploi s he a ailable
memo y. We he e o e conside memo y usage o be he
mos impo an me ic by which o assess ou p oposed
app oach. This will be done by pe o ming a compa a i e
analysis wi h he adi ional echnique o s o ing a single
la ge e ain geome y map and ex u e map.
In Table 4 he memo y usage o a adi ional e ain
geome y map and ex u e map is analysed. E e y elemen o
each map is assumed o be a 16 bi unsigned in ege .
As can be seen om Table 4, he s o age o a single
andomly gene a ed map u ilises a la ge olume o memo y
esou ces. The gene a ion o a small 256 * 256 pixel map
equi es app oxima ely 66% o he en i e 384 KB o RAM
on a GBA. As he map dimensions double, he memo y
equi emen s quad uple.
Nex , he s o age cos o he app oach de ailed in his pape
was analysed – see Table 5. Resul s a e gi en o he cos o
s o ing one hund ed e ain iles bo h in ixed s o age and in
RAM. Each ile consis s o a heigh and ex u e map, and
e e y elemen o a map is an unsigned 16-bi in ege . The
RAM columns display he cos o s o ing he empo a y a ay
o e ain ile e e ences ha is p ocedu ally gene a ed. The
dimensions o his a ay a y depending on he indi idual
e ain ile size. I , o example, a empo a y map o
dimensions 1024 * 1024 pixels is equi ed using e ain iles
o dimensions 8 * 8 pixels, hen a 128 * 128 empo a y
e ain ile e e ence a ay is equi ed.
Indi idual Map Size RAM
256 * 256 pixels 256 kb
512 * 512 pixels 1024 kb
1024 * 1024 pixels 4096 kb
2048 * 2048 pixels 16384 kb
Figu e 10 (a) The empo a y a ay o ile alues ende ed o he sc een.
Each ile is ep esen ed by a sepa a e colou . (b) The associa ed heigh
and colou maps ende ed o he sc een.
Table 2 The compu a ion ime equi ed o he gene a ion o a
1024 * 1024 pixel map using e ain iles o a ying size.
Each alue o he empo a y a ay is a e e ence o a pa icula e ain ile
(a)
(b)
Table 3 The compu a ion ime equi ed o he gene a ion o a new
andom map is minimal as he e ain s uc u e g id size is insigni ican .
Table 4 Values ep esen ing cos o s o ing ull maps in memo y.
© IJIGS/Uni e si y o Wol e hamp on/EUROSIS
Table 5 shows ha he amoun o RAM employed by he
p oposed app oach is minimal. I he indi idual map
dimensions a e inc eased in size by 100%, he amoun o
RAM equi ed educes by 75% whe eas he ixed s o age
equi emen s inc ease by 400%. Howe e , he cos o
s o ing he e ain iles is nominal a smalle sizes, hus
making hem sui able o download o e low bandwid h
connec ions, such as on a mobile phone ne wo k.
Rega dless o he dimensions o he o e all e ain map
equi ed, he igu es p esen ed in he RAM columns o Table
5 emain cons an . This is due o he ac ha , as discussed in
he Implemen a ion sec ion, only a subse o he o e all
e ain map is e e s o ed, ega dless o a ia ion in he
dimensions o he o e all e ain map. The e o e, any size
map could be po en ially ep esen ed on a esou ce-limi ed
de ice such as he Game Boy Ad ance, wi h no implica ions
o he o e all memo y equi emen s.
CONCLUSIONS
In his pape we ha e desc ibed a me hod o ep esen ing he
la ge olumes o da a equi ed o s o e a andom e ain on a
de ice wi h a limi ed amoun o Random Access Memo y
known as he Game Boy Ad ance. By using e ain iles and
Pe lin Noise, we ha e shown how his echnique is
pa icula ly sui able o de ices wi h limi ed p ocessing
powe , as i makes no use o loa ing poin a i hme ic.
The e o e, he e ain ile posi ions can be calcula ed easily a
un ime. In addi ion, a o ally new andom e ain can be
gene a ed apidly, as only he small e ain s uc u e g id
needs o be epopula ed.
I has also been shown ha a massi e e ain can be
ep esen ed using a minimal amoun o bo h ixed and
dynamic memo y. The cos equi ed o s o e he necessa y
e ain iles can be small, hus making his app oach sui able
o de ices wi h limi ed s o age capaci y, and slow download
speeds such as mobile elephones. As only a po ion o he
o e all e ain is s o ed a any one ime, he olume o
memo y used is ixed, ega dless o a ia ion in he
dimensions o he o e all e ain.
Fu u e wo k will in ol e in es iga ing me hods o seamless
blending be ween adjacen e ain iles, so as o p o ide a
mo e uni o m isual expe ience o he use .
ACKNOWLEDGEMENT
This wo k was unded by En e p ise I eland Basic Resea ch
G an SC/2002/129/.
REFERENCES
Dudgeon, J. E. and R. Gopalak ishnan (1996). "F ac al-based
modeling o 3D e ain su aces".In B inging Toge he
Educa ion, Science and Technology, (Tampa, Flo ida, USA, 11-
14 Ap il 1996), IEEE, 246 - 252.
EDGE Magazine (2004). "Mobiles p epa e o 3D e olu ion."In
EDGE Magazine Issue 135, Ap il 2004: 7-9.
Hol kämpe , T. (2003). "Real- ime gaseous phenomena: a
phenomenological app oach o in e ac i e smoke and s eam".In
Compu e g aphics, i ual eali y, isualisa ion and in e ac ion
in A ica, (Cape Town, Sou h A ica, Feb ua y 03 - 05), ACM
P ess, New Yo k, NY, USA, 25 - 30.
Kelley, A. D., M. A. Casey and G. M. Nielson (1988). "Te ain
simula ion using a model o s eam e osion".In 15 h Annual
Con e ence on Compu e g aphics and in e ac i e
echniques1988), ACM P ess New Yo k, NY, USA, 263 - 268.
K eege , K., I. Bi e , F. Dachille, B. Chen and A. Kau man (1998).
"Adap i e pe spec i e ay cas ing".In 1998 IEEE symposium on
Volume isualiza ion, (Resea ch T iangle Pa k, No h Ca olina,
Uni ed S a es, ACM P ess, New Yo k, NY, USA, 55 - 62.
Ma shall, D., A. McCoy, D. Delaney, S. McLoone and T. Wa d
(2004). "A Realis ic Dis ibu ed In e ac i e Applica ion Tes bed
o S a ic and Dynamic En i y S a e Da a Acquisi ion".In I ish
Sys ems and Signals Con e ence, (Bel as , I eland, 30 June - 2
July), IEE, 83-88.
Pe lin, K. (2002). "Imp o ing Noise".In 29 h annual con e ence on
Compu e g aphics and in e ac i e echniques, (San An onio,
Texas, July 23 - 26), ACM P ess New Yo k, NY, USA, 681 -
682.
Picko e , C. A. (1995). "Gene a ing ex a e es ial e ain."In
Compu e G aphics and Applica ions, IEEE Issue 2, Ma ch
1995: 18 - 21.
Rabino ich, B. and C. Go sman (1997). "Visualiza ion o la ge
e ains in esou ce-limi ed compu ing en i onmen s".In 8 h
con e ence on Visualiza ion '97, (Phoenix, A izona, Uni ed
S a es, 19-24 Oc obe ), IEEE Compu e Socie y P ess, Los
Alami os, CA, USA, 95 - 102.
Ri e n, H., T. Voig , M. Tian and J. Schille (2003). "Expe iences
using a dual wi eless echnology in as uc u e o suppo ad-hoc
mul iplaye games".In P oceedings o he 2nd wo kshop on
Ne wo k and sys em suppo o games, (Redwood Ci y,
Cali o nia, May 22 - 23), ACM P ess, New Yo k, NY, USA, 101
- 105.
Slay on, J. (2001). Wilbu Te ain Gene a o
h p://www. idgec es .ca.us/~jslay on/index.h ml.
S einbach, E., B. Gi od, P. Eise and A. Be z (2000). "3-D
econs uc ion o eal-wo ld objec s using ex ended oxels".In
2000 In e na ional Con e ence on Image P ocessing,
(Vancou e , BC Canada, 10-13 Sep embe 2000), 569 - 572.
Ye, A. G. and D. M. Lewis (1999). "P ocedu al ex u e mapping on
FPGAs".In 1999 ACM/SIGDA se en h in e na ional symposium
on Field p og ammable ga e a ays, (Mon e ey, Cali o nia,
Uni ed S a es, Feb ua y 21 - 23), ACM P ess, New Yo k, NY,
USA, 112 - 120.
Te ain Tile
Dimensions Cos o s o e
100 Te ain Tiles RAM
256 * 256 map RAM
512 * 512 map RAM
1024 * 1024 map RAM
2048 * 2048 map
8 * 8 pixels 25 kb 2 kb 8 kb 32 kb 128 kb
16 * 16 pixels 100 kb 0.5 kb 2 kb 8 kb 32 kb
32 * 32 pixels 400 kb 0.125 kb 0.5 kb 2 kb 8 kb
64 * 64 pixels 1600 kb 0.03125 kb 0.125 kb 0.5 kb 2 kb
128 * 128 pixels 6400 kb 0.0078125 kb 0.03125 kb 0.125 kb 0.5 kb
Table 5 Values ep esen ing memo y cos o s o ing he e ain iles and he cos o s o ing empo a y ile alue a ay in Random Access Memo y
(RAM).