TU Wien:Grundlagen der Computergraphik VU (Wimmer)/WS24/25 MC-questions test1

1 Which data structure enables efficient spatial search?

	Octree
	Point cloud
	B-Rep
	Kd-tree
	Regular Grid

2 Which data structures can represent the volume inside an object? For example different densities in a CT scan of a human.

	Octree
	Winged Edge
	BSP-Tree
	Wireframe
	Regular Grid
	B-Rep

3 Which statements about B-Reps are correct?

	Can occlude other objects
	Can represent curved objects accurately
	Combinations are easy
	Contains vertex, face and sometimes edge lists
	Transformations are easy

4 Which statements about Winged Edge data structure are correct?

	For every edge, it sores 2 adjacent edges
	For every edge, it stores 2 adjacent vertices
	Any 2 Winged Edge objects can be combined easily
	The central element of a Winged Edge is a vertex
	For every edge, it stores 2 adjacent faces

5 Which statements about Fourier transform are correct?

	Its inverse converts a function from frequency domain to time domain
	It converts a function from time domain to frequency domain
	Continuous signals can be transformed directly with FFT (Fast Fourier Transform)
	The imaginary part of its result encodes the amplitude

6 Which statements about sampling are correct?

	Accurate reconstruction of a sampled signal is only possible if the sampling theorem is fulfilled
	Sampling converts a discretized signal to a continuous signal
	A Dirac Impulse has infinite amplitude, zero width and an integral of one
	The sampling theorem requires that a band-limited function is sampled with twice the highest possible frequency or higher

7 Which statements about convolutions are correct?

	The convolutions theorem connects convolution and multiplication in time and frequency domains
	Part of the convolution theorem is: F(f1∗f2)=F(f1)∗F(f2)
	The convolution theorem means: Convolution in one space is equivalent to multiplication in the other space
	The convolution of two box functions is two time-shifted box functions

8 Which parameterization method can be used on every possible (all convex and concave) object?

	Manual UV unwrap
	Cuboid parameterization
	Spherical parameterization
	Cylindrical parameterization

9 Which method is a solution for aliasing in the context of texturing?

	Mip-Mapping
	Summed Area Table
	Sub-Surface Scattering
	Cube Mapping

10 Which variables directly or indirectly influence the diffuse component when computing lighting at some surface point p via the Phong Model?

	The normal n at point p
	The viewing direction v
	The reflection of the incoming light \(r = v−2n\)
	The halfway vector h between l and r
	the incoming light direction l

11 Which variables directly or indirectly influence the specular component when computing lighting at some surface point p via the Phong Model?

	The normal n at point p
	The viewing direction v
	The reflection of the incoming light r=v−2n.
	The halfway vector h between l and r
	the incoming light direction l

12 Which variables directly or indirectly influence the specular component when computing lighting at some surface point p via the Phong Model?

	The normal n at point p
	The viewing direction v
	The reflection of the incoming light r=v−2n.
	The halfway vector h between l and r
	the incoming light direction l

13 Which variables directly or indirectly influence the Fresnel reflectance?

	The normal n at point p
	The viewing direction v
	The reflection of the incoming light r=v−2n.
	The halfway vector h between l and r
	the incoming light direction l

14 Which statements on modelling objects are true?

	Blobby objects are an implicit representatio.
	A two-dimensional circle with radius r can be modelled parametically via x=r∗cos(t) and y=r∗sin(t)
	For using cellular texture generation, a surface has to be given explicitly via for example a B-Rep based on triangles
	The tapering transformation is linear, as it can be represented as a matrix
	A three-dimensional sphere with radius r can be modelled explicitly via x2+y2+z2−r2=0

15 Which of the following statements about subdivision schemes is correct?

	The limit surface of a cube is a sphere when using the Catmull-Clark scheme
	The Catmull-Clark scheme preserves the original vertices, meaning it is interpolating
	There is no loss in volume when using Loop's schema
	Loop subdivision is specifically designed for quadrilateral meshes