Computer Graphics Exam for Software Development and Computer Networking Students, Exams of Computer Graphics

Download Computer Graphics Exam for Software Development and Computer Networking Students and more Exams Computer Graphics in PDF only on Docsity! Cork Institute of Technology Bachelor of Science (Honours) in Software Development and Computer Networking – Award (KDNET_8_Y4) Autumn 2008 Computer Graphics (Time: 2 Hours) Instructions Answer THREE questions. All questions carry equal marks. Examiners: Ms. H. Fagan Dr. J. Buckley Dr. A. Kinsella Question 1 i) What is the main difference between parallel and perspective projection? Describe the viewing volume used in perspective projection. (6 marks) ii) What information is specified for a camera when drawing a 3D scene using perspective projection? (3 marks) iii) Show with the aid of an example how would you specify a camera in an 3D openGL program? (3 marks) iv) The camera frame is made up of three vectors named u, v, and n. Show how these vectors are derived from the information specified for a camera. (8 marks) 2 Question 2 i. Explain the purpose of the projection matrix and the model view matrix. How are they modified? (3 marks) ii. Describe the purpose of the call glPushMatrix() and glPopMatrix(). (3 marks) iii. Give an example of two places that you have used callbacks in an openGL program and explain how you would set one up. (4 marks) iv. Write 2 openGL methods; one to draw a unit square and one to draw a triangle in a 2D world. Write a flag method that uses these two shapes to draw a flag. Then write a display method that draws a row of 3 flags. Draw an illustration of the expected output. (10 marks) Question 3 i. What are the main differences between a global illumination scheme and a local illumination scheme? (4 marks) ii. Describe with the aid of a diagram the equations used to calculate diffuse lighting and specular lighting in openGL. (8 marks) iii. What is meant by the attenuation of lighting and how does the lighting calculation allow for this? (4 marks) iv. Describe two ways of speeding up the lighting calculation. (4 marks)