## Computer Graphics - Dec 2016

### Computer Engineering (Semester 4)

TOTAL MARKS: 80

TOTAL TIME: 3 HOURS
(1) Question 1 is compulsory.

(2) Attempt any **three** from the remaining questions.

(3) Assume data if required.

(4) Figures to the right indicate full marks.
**1(a)** What is aliasing? Explain any two anti-aliasing techniques.(5 marks)
**1(b)** Explain OpenGL basic primitives.(5 marks)
**1(c)** Show that the composition of two successive rotation are additive i.e. R(θ1).R(θ2)=R(θ1+&theta2)(5 marks)
**1(d)** What is the pupose of Inside-Outside Tests? Explain with an example.(5 marks)
**2(a)** Write is the mid-point circle drawing algorithm. Using mid-point circle algorithm Plot the circle whose radius = 10 units.(10 marks)
**2(b)** Apply the Cohen - Sutherland line clipping algorithm clip the line with coordinates (30, 60) and (60, 25) against the window with (Xwmin, Ywmin)=(10,10) and (Xwmax, Ywmax) = (50,50)(10 marks)
**3(a)** Explain Weiler- Atherton polygon clipping algorithm in detail.(10 marks)
**3(b)** Expalin Back Surface detection method in detail with an example.(10 marks)
**4(a)** Explain and comapare Goraud Shading and Phong Shading.(10 marks)
**4(b)** What are Parallel and Perspective projections and derive the matrix for perspective projection.(10 marks)
**5(a)** Derive the matrix that represents scaling of an object with respect to any fixed point? Use that matrix to find P^{1} for the given point P(6,8), Sx=2, Sy=3 and fixed point (2,2).(10 marks)
**5(b)** Explain the properties of Bezier curves.(10 marks)

### Write a short note any two Q6.(a,b,c)

**6(a)** Comparison of 3D object representation methods(10 marks)
**6(b)** Construction of Koch curve(10 marks)
**6(c)** Halftone and Dithering techniques(10 marks)