# JNTU Computer Graphics Question Paper

## COMPUTER GRAPHICS

(Computer Science & Engineering)

SET-IV

1. (a) What is the role of digital to analog converter (DAC)? Where is it placed in video display devices?

(b) Explain the mechanism of increasing the colors/gray levels without increasing the frame buffer memory.

2. (a) Draw the flow chart for Bresenham’s incremental circle algorithm in the first octant.

(b) Discuss about the reflections required for generating the complete circle using the first octant of the origin centered circle.

3. (a) List the basic transformations which cause the physical distortion in the transformed object.

(b) An object point P(x,y) is translated in the direction U = aI + bJ and simultaneously an observer moves in the direction U. Show that there is no apparent motion of the object point from the point of view of obsever.

4. Explain the approaches followed in different line clipping algorithms: compare and contrast the characteristics.

5. (a) Distinguish between isometric, diametric and trimetric projections.

(b) Explain with a neat sketch, how the view plane is defined with respect to centre of projections and the object defined is 3-D space.

6. Implement the depth-buffer method to display the visible surfaces of a given polyhedron. How can the storage requirements for the depth buffer be determined from the definition of the objects to be displayed?

7. (a) State the blending function suitable for Bezier surface and explain the terms involved in it.

(b) Demonstrate that Bezier curve is axis independent.

8. Describe the following rules of animation in detail:

(a) Squash and
stretch

(b) Slow-in and Slow out.