PEPERIKSAAN AKHIR SEMESTER I SESI 2004/2005

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PEPERIKSAAN AKHIR
SEMESTER I
SESI 2004/2005
NAMA MATA PELAJARAN
:
REALITI MA Y A
KOD MATA PELAJARAN
BTI4813
KURSUS
3 BTI
TARIKH PEPERIKSAAN
OKTOBER 2004
JANGKA MASA
2 JAM 30 MINIT
ARAHAN
JAW AB SEMUA SOALAN
KERTAS SOALAN INI MENGANDUNGI 12 MUKA SURAT
BTI4813
PART A
INSTRUCTION: Answer all questions.
Virtual reality (VR) is not a new invention, but dated back more than 40 years. It becomes
popular when people like to see things change on the screen in response to their commands
and become captivated by the simulation.
(a) Define the word virtual reality.
(4 marks)
(b) How does virtual reality differ from augmented reality and telepresence?
(5 marks)
(c) The key featureof virtual reality is real-timeinteractivity. What do you understandabout
this?
(6 marks)
Virtual reality is not just a medium or a high-enduserinterface, it also has applicationsthat
involve solutionsto real problemsin engineering,medicineandmilitary.
(a) Explain Morton Heilig's role in the developmentof virtual reality.
(3 marks)
(b) Explain the functionality'of CAVE.
(3 marks)
(c) Describethe first VR productwhichwasproducedby VPL Inc.
(4 marks)
(d) List five (5) classic components of a VR system.
(5marks)
One of the 3 l's defining VR stands for interactivity. In order to allow human-computer
interaction it is necessaryto use special interfaces designed to input a user's commands into
the computer and to provide feedback from the simulation to the user.
(a) List four (4) importanttrackerperformanceparameters.
(4 marks)
(b) Describethe differencebetweenMechanicalTrackersandMagnetic Trackers.
(4 marks)
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(c) List two (2) advantagesof Optical Trackers.
(2 marks)
(d) Describe Gesture Interfaces by giving three (3) examples for its input devices.
(5 marks)
Q4
In computer graphics and computer animation the idea of a viewer or camera is used to
describe the imaginary observer. It is also called as Virtual Observer (VO).
(a) What do you understand with the term of Virtual Observer?
(4 marks)
(b) What will happenif the virtual observer(YO) and actualworld (W) arealigned?Illustrate
the situationby writing the matrix transformation.
(3 marks)
(c) Basedon Figure Q4 below, answerthe following questions.
Yw
Figure Q4
(i)
What is the coordinate ofF' if the point P(l,l,O) is given?
(3 marks)
(ii)
What is the coordinateof p', if the va is offset by (tx, ty, tz) = (10,1,1)and
P(O,l,l) is given?
(5 marks)
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Q5
(a) Below is the actual orientation of both frames of reference. Based on Figure Q5, answer
the following questions using the XYZ fixed angles method.
Figure Q5
(i) Draw a box that hasa coordinate(1,1,1), (0,0,1) and (0,1,0). Sketcha new orientation
ofVO if the following conditionsaregiven:
Roll = 900
Pitch = 1800
Yaw = 00
(tx,.
ty,
tz)=
0.5,0.5,11
(5 marks)
(ii) Substitutethe coordinate(1,1,1)for (x,y,z). What is the new coordinatefor (x',y',z)?
(4 marks)
(b) Answerthe following questionsusingthe XYZ fixed anglesmethod.
If a VO is oriented in a VE using XYZ Euler angles in the sequenceroll, pitch and
yaw andtranslatewith the following values:
Roll = 1800
Pitch = 900
Yaw = 900
(tx,
ty,
tz)
= (2,2,0)
Substitutethe coordinate(1,1,0)for (x,y,z). What is the new coordinatefor (x',y',z)?
(6 marks)
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Q6
(a) Basedon Figure Q6(a), answerthe following questionsusing Direct Cosinesmethod.
Yo
Figure Q6(a)
(i) Rotate the pyramid in Figure Q6(a) through a pitch angle of 900 about the x-axis.
Calculate and sketch the new orientation of the pyramid.
(3 marks)
(ii) A compound rotation can be accomplished by subjecting an object to a sequenceof
matrix operation. Consider the action of rolling the pyramid of Figure Q6(a) about the
z-axis, after performing the 900 pitch rotation. Calculate and sketch the new
orientation of the pyramid after accomplishing the compound rotation.
(5 marks)
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(b) Considerthe scenarioshownin Figure Q6(b), where an object is located-atthe origin of
the ObjectCoordinateSystem(OCS).
Figure Q6(b)
Consider the activities happened in Figure Q6(b). First, roll the object about the z-axis
through an angle of 90° rotations, second,90° pitch rotations about the x-axis and the last
rotation consist of a 90° yaw rotation about the y-axis.
Calculate and sketch the final location of the point p' in the OCS
(7 marks)
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BAHAGIAN A
J awab semuasoalan.
81
Realiti maya (VR) bukanlah satu penemuanbarn, tetapi ia telah wujud sejak 40 tahun yang
lalu. Ia menjadi popular apabila manusia gemar melihat sesuatu benda berubah kerana
bertindakbalas terhadap araban mereka dan mampu disimulasikan.
(a) Takrifkan maksudrealiti maya.
(4 markah)
(b) Bagaimana realiti maya berbeza daripada augmented reality dan telepresence?
(5 markah)
(c) Ciri-ciri utarna bagi realiti maya ialah interaktiviti masa-nyata. Apa yang anda faharn
mengenainya?
(6 markah)
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ARABAN:
Realiti maya bukan setakat satu medium atau antaramuka pengguna tennaju, ia juga
mempunyai aplikasi yang melibatkan penyelesaian kepada masalah sebenar di dalam
kejuruteraan, perubatan dan ketenteraan.
(a) TerangkanperananMorton Heilig di dalampembangunan
realiti maya.
(3 markah)
(b) Terangkan fungsi CAVE.
(3 markah)
(c) Huraikan, produk pertanla VR yang dikeluarkan oleh VPL Inc.
(4 markah)
(d) Senaraikan lima (5) komponen klasik bagi sistem YR.
(5 markah)
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Salah satu daripada 31 yang mentakrifkan VR ialah interaktiviti. Untuk membolehkan
interaksi manusia-komputer,antaramukayang baik perlu direka bagi membolehkanarahan
penggunadimasukkanke dalam komputerdan menyediakanmaklumbalassimulasi kepada
pengguna.
(a) Senaraikan 4 parameterpenting bagi prestasi penjejak.
(4 markah)
(b) Huraikanperbezaandi antaraPenjejakMekanikal dan PenjejakMagnetik.
(4 markah)
(c) Senaraikandua (2) kelebihanPenjejakOptik.
(2 markah)
(d) Huraikan GestureInterfacesdenganmemberikantiga (3) contohperanti inputnya.
(5 markah)
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Di dalam grafik komputer clan animasi komputer, idea pemerhati atau kamera digunakan
untuk menerangkangambaran pemerhati. Ia juga dipanggil sebagai Pemerhati Maya (VO).
(a) Apa yang andafahamdenganistilahpemerhatimaya?
(4 markah)
(b) Apakah yang akan berlaku sekiranya pemerhati maya (VO) dan dunia sebenar (W)
segaris?Ilustrasi situasi tersebut denganmenulis matriks transformasinya.
(3 markah)
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(a) Di bawahadalahorientasisebenarkedua-duakerangkarujukan. BerdasarkanGambarajah
S5,jawab soalanberikutnyamenggunakan
kaedahXYZfixed angles.
Gambarajah 85
(i) Lukis sebuah kotak yang mempunyai koordinat (1,1,1), (0,0,1) dan (0,1,0).
Lakarkanorientasibarubagi VO jika keadaan-keadaan
berikut diberikan:
roll
= 900
pitch
= 1800
yaw = 00
(tXf ty, tZ) = (O~5,O.5,11)
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(5 markah)
(ii) Gantikan koordinat (1,1,1) untuk (x,y,z). Apakah koordinat barn bagi (x',y',z)?
(4 markah)
(b) Jawabsoalanberikutmenggunakan
kaedahXYZfixedangles.
Jika VO diorientasikan di dalam VE menggunakan xyz Euler angles dalam jujukan
roll, pitch clan yaw serta translasi dengan nilai-nilai berikut:
roll
= 1800
pitch
= 900
yaw = 900
(tx,
ty,
tz)
=
(2,2,0)
Gantikankoordinat(1,1,0)untuk (x,y,z). Apakah koordinatbam bagi (x',y',z)?
(6 markah)
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(a) Berdasarkan GambarajahS6(a), jawab soalan berikut menggunakankaedah Direct
Cosines.
Gambarajah S6(a)
(i) Putar piramid di dalam Gambarajah S6(a) melalui sudut pitch 900 terhadap paksi-x.
Kira clanlakarkan orientasi baru bagi piramid tersebut.
(3 markah)
(ii) Compound rotation boleh dicapai dengan meletakkan satu objek kepada satujujukan
operasi matriks. Pertimbangkan tindakan rolling piramid bagi Gambarajah S6(a)
terhadap paksi-z, selepas melakukan putaran pada sudut pitch 90°. Hitung clan
lakarkan orientasi baru bagi piramid selepasmelaksanakancompoundrotation.
(5 markah)
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(b) Pertimbangkansenario yang ditunjukkan di dalam GambarajahS6(b), di mana objek
diletakkanpadaasalanSistemKoordinat Objek (OCS).
GambarajahS6(b)
Pertimbangkan aktiviti yang berlaku di dalam Gambarajah S6(b). Pertama, roll objek
terhadap paksi-z melalui sudut putaran 900 .Kedua, putaran pitch 900terhadap paksi-x
clanputaran terakhir mengandungi putaranyaw 900 terhadap paksi-yo
Hitung clanlakarkan lokasi terakhir bagi titik p' di dalam OCS
(7 markah)
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