Indian Institute of Technology Roorkee (IIT-R) 2009-2nd Year B.Tech Civil Engineering Computer aided graphics, - Question Paper

CE 201 COMPUTER AIDED GRAPHICS
END TERM exam

Summary:
This ques. paper covers topics like graphic pipelines, introduction to computer graphics, color schemes and transformations.

CE-201 COMPUTER AIDED GRAPHICS END TERM EXAMINATION Time: 2hours    Max Marks:- SO

NOTE:- (i) Attempt any FOUR questions in all. Question No. 1 is compulsory.

(ii) Draw diagrams w herever necessary.

1.    (i) What is the basic purpose of colour model?    2 "(ii) Define the term resolution of an image. 2

, (iii) Define the term aspect ratio.    2

(iv) What is dpi of a scanning device?    2 (v) If the size of an image is 640 by 480, draw a diagram to show the pixel values of the

comers of the image?    2

, (vi) What is grey scale?    2

, (vii) Write the transformation equation for convening HSI values    into RGB when the value of H

lies between 120 to 240.    2

. (viii) What are the advantages of using TIFF file format?    2

(ix)    List the attributes of a line.    2

(x)    Draw' the 2D viewing transformation pipeline    2

2.    (a) State the suitability of each colur model for its use in Computer Graphics.    (3) (b) A rectangle A (40, 50), B (60,50), C (60,80) and D (40,80) is mirror reflected about the

line y = 2x. Determine the new coordinates of the rectangle ABCD.    (7)

3.    A right triangle ABC whose hypothenus AB has the coordinates A(4,2) and B(5,0) and is

subjected to the following transformation in succession:-

(a)    Translation to the left by 3 units and upwards by 4 units.

(b)    Scaling with respect to the origin such that s* = 3 and s, = 1.

(c)    Rotation about the origin by 60.

Determine the final coordinates of A, B and C. If the first two transformations are applied in the reverse order, find the coordinates of A, B and C. Draw the new positions for both the cases as given above.    (6+3+1)

4.    (a) A window in the WCS has X extent from 10 to 50 units and Y extent from 0 to 60 units. This window is to be mapped on to a view port having x extent from V* to 1 and y extent from ^lA to V* in the NDCS. Subsequently, the window with x extent from V* to V* and y extent from /i to 1 in NDCS is to be mapped into a view port with x extent from 1 to 10 and y extent from 1 to 20 on to the physical display device. Find the complete view'ing transformation.    (4) (b) Using Bresenhams Algorithm, find the scan points for a circle x² + y² = 81. (6)

5.    (a) Draw the distorted shape of a sqtmrerABCD with A ( 8,5), B (8,9), C (14,9) and D (14,5) as

the vertices when subjected to a shearing by SH_X = 3 and Sh_y = -2.    (5)

(b) State the advantages of making engineering drawing using computer graphics when compared to manual drawing.    (5)

j6. Using Cohen - Sutherland Algorithm clip the lines AB, CD and EF given the coordinates of A (50,-AP), B (350,100), C (120,100), D (270,140), E (30,120) and F (400,-100) for a window defined by the lower left corner of (30,30) and upper right comer (330,330). Draw- a neat diagram also.    (10)

Attachment: indian-institute-of-technology-roorkee--iit-r--2009-b-tech-civil-engineering-2662-1.jpg

Earning:   Approval pending.