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Correct option is (a) CURVE CLIPPING

Easiest explanation: VATTI is USED in polygon clipping. It allows clipping of any number of arbitrarily shaped subject polygons. It can also be used to CLIP any number of arbitrarily shaped polygons.

Right choice is (C) line clipping

Easiest explanation: It is a TYPE of ALGORITHM which is used for line clipping or in other WORDS it is line clipping algorithm. Other EXAMPLES of line clipping algorithms are a Liang-Barsky algorithm and Cyrus-Beck algorithm.

The correct choice is (d) line CLIPPING

The best explanation: SKALA is a type of clipping OPERATION which can be used for a line or line-segment clipping against a RECTANGULAR window, as well as against a convex polygon. Its algorithm is based on homogenous co-ordinates and duality.

Right option is (a) outside, inside

The EXPLANATION: Line clipping FOLLOWS the same algorithm that is in the case of point clipping. So, in line clipping also, we will CUT the PORTION of the line which is outside of the window and keep only the portion that is inside the window.

The CORRECT OPTION is (b) False

Easiest explanation: We can’t resize the bitmap IMAGE. When the bitmap image is RESIZED, the image pixels GET distorted. It is one of the main disadvantages of the bitmap.

Correct CHOICE is (C) 3

Easy explanation: There are THREE methods for text clipping which are −

1) All or none string clipping2) All or none CHARACTER clipping3) Text clipping.

Correct choice is (a) True

Explanation: A POLYGON can also be CLIPPED by SPECIFYING the CLIPPING window. Sutherland Hodgeman polygon clipping algorithm is used for polygon clipping.

Right option is (C) Size and proportions

For explanation: By changing the DIMENSIONS of the VIEWPORT, the size and proportions of the objects being displayed can be manipulated, this leads to the zooming effect of the image by SUCCESSIVELY mapping different dimensioned clipping windows on a fixed SIZED viewport.

The correct choice is (B) REMOVING OBJECTS and lines

Easiest explanation: The primary use of CLIPPING in computer graphics is to remove objects, lines, or LINE segments that are outside the viewing pane.

The correct OPTION is (b) False

To explain: The technique in which users can change the SIZE of the AREA to be viewed in order to see more detail or less detail is called ‘Zooming’. Panning MEANS sliding the camera.

The correct answer is (a) Sx = (svmax – svmin)/ (swmax – swmin)

For explanation: The mapping or transformation involves DEVELOPING formulas that start with a POINT in the world window, say (xw, yw). The formula is used to produce a CORRESPONDING point in viewport COORDINATES, say (XV, yv). So after keeping it proportional in ‘x’ co-ordinate, we get, (svmax– svmin)/ (swmax – swmin).

The correct choice is (d) INTERFACE window

Explanation: In common words, it is termed as a GRAPHIC user interface. It allows users to interact with electronic DEVICES through graphical icons and visual indicators such as SECONDARY notation.

Correct ANSWER is (c) World window

Explanation: The world window SPECIFIES which part of the window needs to be drawn. It ALSO defines which part of the window should be drawn and which part OUTSIDE the window should not be drawn and should be clipped away.

The correct option is (b) Screen co-ordinate system

For explanation: The coordinate system of the screen is a CARTESIAN coordinate system. The ORIGIN (0,0) is at the top left of the screen. Point is denoted by (X,y), where x is x co-ordinate and y is y co-ordinate.

The correct option is (a) World co-ordinate system

For explanation: World Coordinate System ALSO called as WCS is any coordinate systems that describe the PHYSICAL coordinates associated with a data ARRAY. They also used for an astronomical image, or for determining the WAVELENGTH scale for a spectrum.

The correct option is (B) YWMIN > y > ywmax

To elaborate: A point P(X,y) is NOT clipped if y is more than the MINIMUM value of y and less than the maximum value of y. Mathematically, it can be written as“ywmin ≤ y ≤ ywmax“.

Correct OPTION is (d) solid clipping

For EXPLANATION I WOULD say: Since clipping is done in 2 dimensional viewing and solid is a 3 dimensional object so clipping algorithm can’t be applied on a solid object. Instead of solid clipping, there is another TYPE of clipping algorithm KNOWN as curve clipping.

The correct choice is (c) clipping

The best I can explain: Clipping is the PROCESS of CUTTING out extra material. In the context of computer graphics, clipping is a METHOD to selectively enable or disable rendering operations WITHIN a defined region of INTEREST.

Right answer is (B) 2

The EXPLANATION is: CLIPPING algorithm can be applied in two ways for 2d transformation VIEWING. Two ways in which clipping algorithms can be applied are- 1) world co-ordinate clipping.2) VIEWPORT clipping.

The CORRECT ANSWER is (C) vector co-ordinates

To explain I would say: Vector co-ordinates are used to denote VECTORS which are physical quantities having magnitude as well as direction. In 2d viewing transformations- MODELLING co-ordinates, viewing co-ordinates, Normalised co-ordinates and Device co-ordinates are used.

The correct CHOICE is (d) WORLD co-ordinates

To explain I would say: World Coordinate Systems (WCS) are the type of coordinate systems which describe the physical coordinates associated with a DATA array, such as sky coordinates. It is also used to denote wavelengths of a SPECTRUM and to draw astronomical images.

The CORRECT ANSWER is (a) True

To explain I would say: When we display a scene, only those objects which have a particular window are displayed. So for that mechanism to work, co-ordinates are made to range themselves according to the SCREEN resolution.

The CORRECT choice is (B) TOTAL

The explanation: We CONSIDER a formal mechanism of view, that is, which part of the picture is to be displayed. That’s why we select a view by specifying a sub-area of the total picture area.

The CORRECT option is (a) M^-1 = M^t

The best I can EXPLAIN: Due to the effect of similitude and similarity TRANSFORM, the inverse is equal to the TRANSPOSE. So, we can say that M^-1 = M^t.

Correct answer is (d) homogenous co-ordinates

The explanation is: The FUNCTION of homogenous co-ordinates is to allow common vector OPERATIONS such as translation, rotation, scaling and PERSPECTIVE projection to be REPRESENTED as a matrix by which the vector is multiplied.

Right ANSWER is (a) True

For EXPLANATION I would say: The ratio of length GETS preserved, for example, distinct collinear points x1,x2,x3. The ratio of X1X2 and x2x3 is same as that of F(x1)f(x2) and f(x2)f(x3).

The correct answer is (c) concavity

For explanation I would say: The col-linearity, convexity and PARALLELISM of bunch of points are conserved in AFFINE transformations but any 3 or more points which are CONCAVE can TURN parallel, so we can say concavity is not conserved.

Right choice is (d) LINEAR, affine

The BEST I can explain: Linear and affine transformations are two different types of transformations of matrices. In linear, POINTS are in vector space but in affine, points are in affine space.

Correct answer is (c) 9

For explanation I WOULD say: In a co-ordinate system, any position of a point is denoted as (X,y,z). Where z DENOTES the perpendicular distance of the point from the z-axis. Hence z is the Z co-ordinate.

Correct OPTION is (b) 8

Easiest explanation: In a co-ordinate system, any POSITION of a point is denoted as (x,y,z). Where y denotes the PERPENDICULAR DISTANCE of the point from the y-axis. HENCE y is the Y co-ordinate.

The correct choice is (a) co-ordinate system

Explanation: A coordinate system is a system which uses one or more numbers, or COORDINATES, to uniquely determine the position of a POINT. It also DETERMINES the other GEOMETRIC elements on a MANIFOLD on Euclid space.

Correct CHOICE is (d) 5

The best explanation: The ‘3 x 3’ matrix which shears in ‘y’ direction will have TOTAL 9 elements, 3 of which are ‘1’, 5 zeroes and 1 VARIABLE in a lower TRIANGLE which is the scaling factor.

Right choice is (d) Skewing

Explanation: In the case of SHEAR only ONE coordinate CHANGES its COORDINATES and other preserves its values, that’s why it is ALSO called skewing.

Right option is (b) False

For explanation I WOULD say: Shearing and reflection are not TYPES of translation. They are types of transformation. Even translation is ALSO a TYPE of transformation.

Right answer is (d) (x, y) → (x+ay, y+bx)

Easy explanation: The first one REPRESENT TRANSLATION, the SECOND one represents SCALING, THIRD one rotation and the last one is representing shearing.

The CORRECT choice is (c) -1

Best explanation: The pure reflection matrix is:

[T] =| 10 |

| 0-1|

So, the determinant will be = (1) (-1) – (0) (0) = 0.

Correct ANSWER is (a) Pure rotation

The best explanation: When we apply reflection ONE time, it rotates the image by 180 DEGREES. So, if we REPEAT it 2 times the total reflection will be of 360 degrees.

The correct OPTION is (c) 180 degree

Easy explanation: Reflection is the mirror image of the original OBJECT. It ROTATES the object 1890 degrees. The left SIDE image is formed into right side and VICE versa.