課程名稱︰虛擬實境
課程性質︰選修
課程教師：歐陽明
開課學院：電資學院
開課系所︰資工所、網媒所
考試日期（年月日）︰2015.05.18
考試時限（分鐘）：
試題 :
Virtual Reality Mid-term Exam, May 18, 2015
1. (10%) In your opinion, what are the great technology breakthroughs of
Virtual Reality and Augmented Reality in the past ten years? Please list
5 such items in relative importance, and give very short explanations why
it is important.
2. (25%) Head-Mounted Display
Assume you are an engineer sitting in the office and you are anxious about
the Google I/O in 2015 because you are in charge of designing Google
Cardboard Part 2.
(a) (5%) You start from hardware of Google Cardboard. Explain why you need
two lens(透鏡) for your device. (Hint: What kind of lens will you need?
What are the functions of the lens? )
(b) (5%) After assembling all components, you start to design the software.
You put figure 1 in your cellphone and start to watch it, but you found
it to be blurry. What kind of adjustments for image will you need in
your software? (Hint: What is the effect by lens and binocular
vision(雙眼視覺)?)
http://i.imgur.com/NIWHBhx.png
(Figure 1: Same image in both left and right side)
(c) (8%) You can see an image without blur but it is not with enough
resolution. The length and width of your screen is 12 and 6 cm
respectively and the distance between your eyes and screen is 6 cm.
How many points will you need in your screen at least to achieve the
best resolution? (Hint: Visual acuity: eye's ability to distinguish
two points of light is limited to 2.0 mm at a distance of 10 meters.)
(d) (5%) Finally, you start to test your device. By using the gyroscope in
the cellphone, you can pitch, roll and yaw. If you want to increase
another inputs besides the gyroscope, please describe how to make the
cardboard device obtain such information? Describe your methods in
brief.
(e) (2%) If you are about to publish Google Cardboard Part 2 next week.
What kind of applications will you use?
3. (25%) Augmented Reality and Virtual Reality
http://i.imgur.com/WpPnHCu.png http://i.imgur.com/hd5X2oa.png
(Figure 2: Oculus Rift(Left) and Microsoft HoloLens (Right))
VR and AR are popular in recent years. Oculus Rift and Microsoft HoloLens
are two such products which have high publicity.
(i) (10%) What's the difference between Augmented Reality (AR) and
Virtual Reality (VR)? Please classify the products (Oculus Rift and
MSFT HoloLens) and explain it with your reasons.
(ii) (10%) One of core functions in Oculus is how to accurately determine
the user's head movement. In order to improve user experience, Oculus
uses a camera to assist it. Please explain why this camera can help
Oculus to determine the user's head movement. Also, describe possible
problems of this camera.
http://i.imgur.com/wHb27w8.jpg (Figure 3)
(iii) (5%) In HoloLens promotional vedio, there is a scenario that a woman
is guiding by her father how to install the pipeline with some helpful
virtual information such as installation path (Figure 3). Please
analyze what kind of technology will be used in order to achieve
the above result.
4. Term project (5%)
What is the term project you want to do for this semester? What kind of
technical problems will you encounter and have to be solved?
5. (10%) From one camera, you are looking at a triangle with known vertex
positions, such as A(0, 40, 10), B(60, 30, 10), C(10, 0, 10).
(a) (5%) How to determine the distance and orientation of the camera to the
triangle?
(b) (5%) In actual use, there are cases when one vertex of the triangle is
blocked from the camera's view. What would be possible solutions to this
problem? Please state your solution clearly and with explanation.
6. (10%) Suppose we are going to use only two speakers to implement a
5-speaker Dolby AC-3 sound system in your study room. What will be the
technical problems you have to solve instead of using headphones only?
Give your formula or algorithms. Tell us what's missing (difficult to
calculate) in your solution?
7. (15%) This problem is about hierarchical animation, and you can answer it
in your familiar computer language (package).
In the source code "dance.c" of VR homework, a man consists of the
following parts: head, body, right(left) upper arm, right(left) lower arm,
right(left) hand, right(left) upper leg, right(left) lower leg , right(left)
foot.
Suppose the behavior of this man is a little different from a normal human.
He has the following additional behavior:
A. When right(left) upper arm moves, the left(right)upper leg does the
same moving.
B. When right(left) lower arm moves, the left(right)lower leg does the
same moving.
Besides the above three behavior, the moving of this man is exactly the same
as a normal human.
(i) (5%) How to make this display suitable for Google Card Board VR HMD
(with stereo display)? What are the essential software
solutions/function calls in your language/package such as in OpenGL
or in Unity3D?
(ii) (10%) How to represent this strange human-like model with properties
A and B in your own way? Either in OpenGL, Uni3D, or other packages.