# IPU BCA Semester 5 - Computer Graphics - End Term Examination Paper - 2014

END TERM EXAMINATION

## COMPUTER GRAPHICS

(BCA-303)

### FIFTH SEMESTER [BCA], DECEMBER 2014

**Time**: 3 hours

**Maximum Marks**: 75

**✍ Note**: Attempt five questions. Question no. 1 is compulsory. Select on question from each unit.

**Question 1**: Write short note on the following:

(a) Touch Panel Screen

(b) Antialiasing

(c) Significance of 4- bit code in line clipping

(d) Matrix representation of 2-d shearing

(f) Primitive instancing

(g) Projections

(h) Vanishing Point

(i) Object space method

(j) Frame buffer

**Question 2**:

(a) Describe Mid Point line drawing algorithm with its complete derivation.

(b) Scan convert the straight line using Mid point line algorithm whose end points are (0,0) and (5.5).

**Question 3:**

(a) Distinguish between following:

(i) Interactive Vs Non interactive graphics.

(ii) Raster Vs Randon scan display.

(b) Discuss Cohen-Sutherland line clipping algorithm with a suitable example.

**Question 4**:

(a) What do you understand by window port and view port? Briefly describe the steps to transform an object from window port to view conversion.

(b) Consider a square A(1,0) B(0,0) C (0,1) D(1,1). Rotate the square ABCD by 60 degree clockwise about the point A(1,0). Also draw the transformed square.

**Question 5:**

(a) Prove that two successive 2-D rotations are additive in nature i.e. R(Î±) R(Î²)= R (Î±+Î²).(6.5)

(b) Reflect a diamond shaped polygon whose vertices are A(-1,0), B(0,-2), C(1,0) and D (0,2) about (i) the horizontal line y=2 and

(ii) the vertical line x=2.

**Question 6**:

(a) Explain that how solids are represented by using Boundary representation (B-rep) technique and Constructive Solid Geometry (CSG) technique.

(b) Describe polygon meshes.

**Questions 7**:

(a) State the properties of Bezier curve. For the cubic Bezier curve (n=3), find all the blending functions and Bezier matrix.

(b) what do you mean by b-spline curves? Identify the difference between B-spline and Bezier curve.

**Question 8**:

(a) How parallel projections are different from perspective projections? Explain by discussing suitable example.

(b) Perform a perspective projection on to the x=0 plane of the unit cube where centre of projection is at xc = -10, yc = - 10 and zc = - 10.

**Question 9:**

(a) What is the hidden surface removal method? Why do we need remove hidden surface? Discuss the depth buffer (Z buffer) algorithm for hidden surface removal.

(b) Distinguish between the following:

(i) Cavalier vs. cabinet projections

(ii) 2-D clipping vs. 3-D clipping