Revision Sheet Computer Graphics and Human Interaction By Dr. HANY ELSALAMONY1

1. What is meaning of computer graphics? Give application examples. 2. What are the steps to creating a picture? 3. Define: a) Screen Resolution b) CRT c) Color resolution of the monitor d) Color index mode e) Clipping area f) The viewport g) Rasterizing h) Geometric transformations. i) Object space. By Dr. HANY ELSALAMONY2

4. There are three kinds of transformations: a)………. b)………. c)………… 5. Write in details about translation with examples. 6. Write in details about scaling with examples. 7. Write in details about rotation with examples. 8. What is the double buffering? Write in details. By Dr. HANY ELSALAMONY3

9. If there exist a circular shape with centre at the origin and radius 2. Draw the scaling to point (0, 4), and (4,0). 10. Translate withdrawing the same figure in (9) into centre (2,8)and the same radius. 11. If there exist a point (3, 5) in a shape, rotate it by angle 45º around Z-axis. And draw it. 12. Write in details about raster image file? By Dr. HANY ELSALAMONY4

13. The basic format of the bmp file consists of: a)…….. b)……..c)………d) ……… What are differences between: header and image information section 15. Complete the graph: a) b) By Dr. HANY ELSALAMONY5

16. What is the idea behind the image processing? 17. In image enhancement there exist famous two techniques: a) …………. b)……………. 18. In image compositing there are two popular techniques, what are they? Give examples for each one. By Dr. HANY ELSALAMONY6

19. What is the meaning of red eye- treatment? and what is the technique of in programming to use it? 20. The most popular and commonly used method to model objects is to use small polygons to approximate the surface. This method is popular due to: (a)………….. (b)…………….. (c)…………... By Dr. HANY ELSALAMONY7

21. What is the meaning of: (a) Single area in polygon. (b) Convex requirement area. c) Back-face culling. d) Polygon mesh e) MAXSHAPES f) MCOORDS g) Rendering process By Dr. HANY ELSALAMONY8

22. Which of these graphics in the following figure is a convex area: By Dr. HANY ELSALAMONY9

23. If Tx=2, Ty=3, Tz= 4, find the translation matrix in 3D, when the first point is (x, y, z) find the new point. 24. The components of rendering process are: a)………….. b)………….. c)………….. d)………….. e)………….. By Dr. HANY ELSALAMONY10

25. What are the meaning of shading, lighting, hidden surface removal, z-buffer, and phong processes? 26. The reflectance divided into four components which are: a)………….. b)………….. c)………….. d)………….. By Dr. HANY ELSALAMONY11

27. What are the differences between the ambient, diffuse, Specular Reflectance, and Emission reflectance? 28. if the incident light has an ambient color of (Ri, Gi, Bi) and the object it hits has a material with ambient reflectance of (Ra, Ga, Ba) then the reflected light due to ambient reflection will have a color defined as: (Rra, Gra, Bra) = By Dr. HANY ELSALAMONY12

29. If we assume the light to have a diffuse color of (R id, G id, B id ) and the surface to have a diffuse reflection coefficient of (R d, G d, B d ). then the diffuse color component of the reflected light can be calculated as: By Dr. HANY ELSALAMONY13 (R rd, G rd, B rd )=

30. If the angle in diffuse reflection between the incident light and the normal to the surface at the point of incidence more than 90 degrees causes: ……………… 31. specular reflection depends on three components: a)…………….. b)…………… c)…………….. By Dr. HANY ELSALAMONY14

31. The specular reflection color function can be defined as: 32. What are the meaning of texture map, texels and environment mapping? 33. What is the idea behind the cube environment mapping? By Dr. HANY ELSALAMONY15 (R rs, G rs, B rs )=

By Dr. HANY ELSALAMONY16