IMGD 1001 Practice Final Exam Solution

1. What is a reference as it relates to visual design and production for games?

   Ans: A reference is a picture of a real-world object that can be used
   as an example to make a digital representation of the object.  The
   reference can help with proportions, colors and textures.  For
   example, modeling and rendering sofa would be much easier with a
   picture of a real couch as a reference in order to get the arms
   proportioned right and the fabric right.
   
   

2. What do we refer to when we talk about using "broad strokes" for artistic rendering? Provide an example.

   Ans: Broad strokes refers to doing the most visually outstanding parts
   of a work first and then filling in the details later.  For example,
   broad strokes of an (outdoor) house would first put in a basic cube
   house with cylindrical trees to get proportions right.  Then, simple
   textures or colors (green for the trees, brown for the ground) would
   be added to get a "feel" for the scene before adding further details.
   

3. What are some of the differences between NURBS and Polygonal modeling?

   Ans: NURBS uses curved surfaces based on a few points, while polygonal
   modeling uses points for vertices with edges between them.  Polygonal
   surfaces are straight-forward and easy to render but are manually
   intensive to create.  NURBS are resolution independent but have seems
   difficult to overcome.  (There are more details that can be provided
   here.)
   

4. What are faces, normals and backface culling as they related to polygonal modeling?

   Ans: A face is the flat size of a polygon.  A normal is a vector at
   a right angle to the face.  Backface culling is the process of removing
   polygons that are not rendered on a screen.
   

5. Briefly describe some ways to effectively reduce the polygon count, with examples where appropriate. Why might you want to do this?

   Ans: Use backface culling to remove faces that cannot be seen (ex -
   remove the bottom polygon on a barrel that can't be moved).  Reduce
   some of the polygons used to make a curved surface (ex - render the
   barrel sides with 12 polygons instead of 20).  Being able to remove
   polygons that do not affect the image scene quality (much) is
   important to reduce the size of a game image and make it faster to
   render.
   

6. What is box modeling?

   Ans: Modeling a basic shape as a box (or other primitive polygon)
   and using extrude and cut and edit to achieve a model of the shape
   desired.
   

7. What is a texture and how does it relate to a shader?

   Ans: A shader defines the surface property of an object (ie- how
   shiny, bumpy, how light effects it).  A texture is a bitmap that is
   plugged into shader that defines image we want to appear on object
   (ie- such as a picture of letters on an otherwise flat sign).
   

8. What is an alpha channel?

   Ans: A grayscale image embedded in the "extra" 8 bits of 32-bit image,
   and used in graphics rendering for transparency, reflection and bump
   maps.
   

9. Provide some brief examples of how lighting can be used to influence mood.

   Ans: Color can be used to indicate mood.  For example, a green wash
   can indicate peace for the player while a red wash can indicate
   warning.  Lighting can indicate mood, with shadows providing mystery
   or warning.
   

10. What is a key light? What is a fill light? What kind of light would you use to make "pools of light" in a scene?

    Ans: A key light is the main light source, the most intense and the
    majority.  It's put at angle to define 3-D forms.  A fill light brings
    out some details out of shadow and works well at angle.  A backlight
    is placed behind and slightly above or below object to help define
    shape.  It highlights edges, pulls away from background.  To make a
    pool of light, an artist would probably use spot lights with focused
    beam on single location since they provide great control over the
    lighting.
    

11. What is a sound designer as a member of a game development team?

    Ans: A sound designer brings life-like (and beyond life) sounds to
    game.  They are increasingly a critical member of the game dev
    process, as audio has more capability and more importance
    

12. What is the sampling rate when applied to capturing audio? Why not always sample at the highest rate possible by the hardware?

    Ans: Each sample provides a number that needs to be stored, sent over
    a network and/or played.  The higher the rate, the more
    processing/storage required.  This is especially meaningful since a
    high sampling rate may note be required for adequate fidelity.
    

13. What is the typical sample size and sample rate for voice?

    Ans: 8000 samples per second with each sample being 8 bits.
    

14. Describe one technique MP3 compression uses to compress audio data.

    Ans: A lot of possibilities here ... removes redundant data and
    irrelevant data.  Compresses in the time domain and in the spatial
    domain. Filters waveform into sub-bands and prioritizes bits in each
    band based on importance.
    

15. Why might ambient background music be a mistake?

    Ans: It might not reflect the current emotional context of the game.
    Player tunes it out.
    

16. Name one good tip for using music in a game.

    Ans: Many possibilities: follow the dramatic arc with the game's
    sound track, never use music unless it is making a specific emotional
    statement to the player, get the composer involved early in the
    process, the more content the better, ...
    

17. Name 2 out of the 3 programming areas talked about in class.

    Ans: The three are: Game code, Game Engine and Tools.
    

18. What is the code and fix method of software engineering?

    Ans: really, it is no methodology at all.  Instead of any
    kind of design, programmers jump right in and write code.
    When the code is ran (no formal testing) if there are bugs,
    they are fixed.  The process repeats in the hope a working
    game comes out.
    

19. What is version control software? Why is it useful?

    Ans: A database containing files and past history of them.  It
    provides a central location for all code and allows the programming
    team to work on related files without overwriting each other's work.
    the database preserves the history to help track down errors and
    provides branching and merging for platform specific parts.
    

20. Name one advantage of C++ over Java. Name one advantage of Java over C++.

    Ans: Many choices here.  C++ typically provides opportunities for
    better performance.  Java takes care of memory management that
    can cause hard-to-find bugs for C++ programs.
    

21. Name the steps in the process of debugging, as discussed in class.

    Ans: Reproduce the problem consistently, Pinpoint the error, Repair
    the problem and Test solution
    

22. What is the goal of AI in a computer game opponent?

    Ans: To lose in a challenging way.  The goal is for the player to win,
    but only by using skill and strategy, not because the AI is noticeably
    "dumb".
    

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