Game Development Final Exam Questions
And Answers
sprite -
correct answer ✅a 2-dimensional image or animation, generally
with transparent parts overlaid onto other screen info, floating
above it without altering it (though the term may also be applied to
a background)
originally in hardware, like fixed-image screen cursors: limited
number and variety
now, with 3D graphics, applies to flat images superimposed on 3D
screens
transparency may involve special color codes, or additional bit
masks
takes some time: double buffering often necessary to avoid flicker
and tear
animated sprites -
correct answer ✅often looping (while pixel art is okay for one-off,
it is very expensive for animation purpose)
obtainable in several ways:
- filmed performance
- "rotoscoping": animation by artist of filmed performance by
actors
,Game Development Final Exam Questions
And Answers
- "claymation": where live actors cannot be useful (eg. Wallace &
Gromit)
- pre-rendered Computer-Generated Imagery (CGI) where a
dynamic (maybe 3D) scene can be generated, but not generated
fast enough for use in game
- ripping from other sources (movies, games, image databases,
etc.)
billboarding -
correct answer ✅technique that exploits the face-forward
property of sprites
- useful eg. to create a glow or a halo around another image
- 3D rendering engines can process "3D sprites" faster than general
3D objects
3D polyhedral models cannot cheaply & realistically handle effects
in 3D, they may be oriented as if from a point, or just turn about
the axis
the same principles can be used to make an object appear to turn
to face some other object in a 3D scene, not just the camera
2.5D -
correct answer ✅3 interpretations:
,Game Development Final Exam Questions
And Answers
1. stereoscopic vision in depth perception
2. 2D gameplay set in a 3D-modeled scene
3. using projections or a series of images to simulate 3D
appearance
axonometric projection -
correct answer ✅non-use of perspective; foreshortening of 3 axes
- isometric: all 3 the same (engineering drawings)
- dimetric: 2 of the 3 the same, lessens anit-aliasing problems (2:1
pixel ratio)
- trimetric: no 2 the same
sprite-based "exact" collision detection -
correct answer ✅sprites have transparent pixels, visible pixels;
sprites overlap if after scaling, translation, rotation, they share
visible pixels
gives precise detection of collisions, but
- it is an expensive operation to perform (especially if scaled and/or
rotated)
- collisions are in practice relatively rare and that expense may get
wasted
, Game Development Final Exam Questions
And Answers
- precision may not even be what is wanted, especially if collision
response changes sprite (it may cause new sprite to have no
collision, change back to old, ..., and loop)
multi-phase collision detection -
correct answer ✅O(N^2) complexity of sprite/sprite comparisons;
very costly
reduce complexity of individual sprite/sprite comparison
- broad phase: quickly eliminate pairs that cannot possibly be in
collision
- narrow phase follows: determine pairs that are actually in
collision
- middle phase is also possible: determine pairs that must be in
collision
axis-aligned bounding box (AABB) -
correct answer ✅minimum bounding box subject to the constraint
that the edges of the box are parallel to the (Cartesian) coordinate
axes
used to an approximate location of an object in question and as a
very simple descriptor of its shape
And Answers
sprite -
correct answer ✅a 2-dimensional image or animation, generally
with transparent parts overlaid onto other screen info, floating
above it without altering it (though the term may also be applied to
a background)
originally in hardware, like fixed-image screen cursors: limited
number and variety
now, with 3D graphics, applies to flat images superimposed on 3D
screens
transparency may involve special color codes, or additional bit
masks
takes some time: double buffering often necessary to avoid flicker
and tear
animated sprites -
correct answer ✅often looping (while pixel art is okay for one-off,
it is very expensive for animation purpose)
obtainable in several ways:
- filmed performance
- "rotoscoping": animation by artist of filmed performance by
actors
,Game Development Final Exam Questions
And Answers
- "claymation": where live actors cannot be useful (eg. Wallace &
Gromit)
- pre-rendered Computer-Generated Imagery (CGI) where a
dynamic (maybe 3D) scene can be generated, but not generated
fast enough for use in game
- ripping from other sources (movies, games, image databases,
etc.)
billboarding -
correct answer ✅technique that exploits the face-forward
property of sprites
- useful eg. to create a glow or a halo around another image
- 3D rendering engines can process "3D sprites" faster than general
3D objects
3D polyhedral models cannot cheaply & realistically handle effects
in 3D, they may be oriented as if from a point, or just turn about
the axis
the same principles can be used to make an object appear to turn
to face some other object in a 3D scene, not just the camera
2.5D -
correct answer ✅3 interpretations:
,Game Development Final Exam Questions
And Answers
1. stereoscopic vision in depth perception
2. 2D gameplay set in a 3D-modeled scene
3. using projections or a series of images to simulate 3D
appearance
axonometric projection -
correct answer ✅non-use of perspective; foreshortening of 3 axes
- isometric: all 3 the same (engineering drawings)
- dimetric: 2 of the 3 the same, lessens anit-aliasing problems (2:1
pixel ratio)
- trimetric: no 2 the same
sprite-based "exact" collision detection -
correct answer ✅sprites have transparent pixels, visible pixels;
sprites overlap if after scaling, translation, rotation, they share
visible pixels
gives precise detection of collisions, but
- it is an expensive operation to perform (especially if scaled and/or
rotated)
- collisions are in practice relatively rare and that expense may get
wasted
, Game Development Final Exam Questions
And Answers
- precision may not even be what is wanted, especially if collision
response changes sprite (it may cause new sprite to have no
collision, change back to old, ..., and loop)
multi-phase collision detection -
correct answer ✅O(N^2) complexity of sprite/sprite comparisons;
very costly
reduce complexity of individual sprite/sprite comparison
- broad phase: quickly eliminate pairs that cannot possibly be in
collision
- narrow phase follows: determine pairs that are actually in
collision
- middle phase is also possible: determine pairs that must be in
collision
axis-aligned bounding box (AABB) -
correct answer ✅minimum bounding box subject to the constraint
that the edges of the box are parallel to the (Cartesian) coordinate
axes
used to an approximate location of an object in question and as a
very simple descriptor of its shape
