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1 cis.pku.edu.cn

2 2 g g g g g g g

3 3

4 4

$;, \ \ \$ $\ ; ;$

5 5 1.1 ; ;, \ \ \ \ ; ;

6 1.1 6

7 1.1 7 No illumination Constant colors Polygons Parallel light Diffuse reflection Free-form surfaces

8 1.1 Parallel light Specular reflection Multiple local light sources 8

9 D-Image-Textures Bump-Mapping Reflection textures

10 Few Polygons More Polygons

11 1.1 11

12 1.2..,... b u 8 + v 8. g( u, v) = { a u 8 + v 8.. f ( u, v) = A(cos( pu) + cos( qv)) 12

13 X Y Z

14 14 1.2

15 1.3 ( ) "Carve the shape out of the texture matter" 15

16 D textures are useful for: (1)volume rendering and examining a 3D volume one slice at a time; (2)animating textured geometry, for example, people that move; (3)solid texturing, for example, wood, marble and so on; (4)eliminating distortion effects that occur when you try to map a 2D image onto 3D geometry;

17 u, v, w w s, t, r, q q

18 18 1.5

19 19 g

20 20 g : : :

21 21 g

22 22 g : : :

23 23 g

24 24 g

25 25 g OpenGL gltexgen

26 26 g

27 27 g (1) DirectX OpenGL (2) (3) DirectX OpenGL (4) DirectX OpenGL (1) (2) (3) (4)

28 28 g (1)RGB (2) (3)RGB

29 29 g (1) (2) (3)

31 31 g 32 64

32 32 g : t(x, y) x y (p u, p v ) b

33 33 g

34 34 g ( ) Mipmapping SAT Summed Area Table

35 35 g (Mipmapping),. mip multum in parvo 2 2 d

36 36 g ( ): d?

37 37 g ( ): ( ) :

38 38 g ( ) : u v RipMapping.

39 39 g 16 0, 0

40 40 g 16:1 ATI Radeon

41 41 galpha g g g g g

42 4.1 Alpha : : (Rs,Gs,Bs,As) :(Rd, Gd,

42 Alpha : : (Rs,Gs,Bs,As) :(Rd, Gd, Bd, Ad) : (Sr, Sg, Sb, Sa) (Dr, Dg, Db, Da)

43 Alpha g alpha

44 Phong,.

45 4.2 45

46 Gloss Mapping.

47 4.2 t diff RGB i diff t gloss i spec 47

48 Blinn Newell EM EM

49 EM

50 4.3 1: : 2:. : EM EM 50

51 Blinn Newell 1976 Blinn Newell, 0 2 0, [0, 1] u, v Blinn Newell

52 4.3 Blinn Newell : (1) ; ( ) (2) =0 ; ( ) (3) ;( ) (4).( ) 52

53 ( 1986 Greene ),

54 ( ): (1) ; (2) ; (3) (4) ; (5) ;( )

55 55 4.3, Williams Miller Hoffman

56 ( )

57 ( ) A f u h

58 ( ) r = e 2(n e )n n : surface normal e : r :

59 ( ) ( Blinn Newell )

60 4.3 Heidrich Seidel 60

61 z : ( ) r z

62 62 4.3

63 4.4 Blinn

64 b u b v u v

65 : (1), (2)

66 (y)/ 2 +.5

67 Displacement Mapping

68 4.4 : 68

69 u, v Gouraud

70 4.4 Texture Map Bump Map Shifted Bump Map The result of the subtraction gives us the light map Combine this lightmap with the original texture 70

71 t u l x u l y v. u, v (n, t, b) l x l y (l x, l y r r

72 72 4.4

74 (1) DirectX 9 (2) (3) : - - -

75 75

76 76 g? g? (1) (2) Tiling Mosaicing : (3) LRU, Least Recently Used. (4) MRU, Most Recently Used. (5) :. (6) :.

The viewer looks at a texture from only one location.

77 77 The clipmap algorithm is based on the following constraints: The viewer can see only a small part of a large texture from any given viewpoint. The viewer looks at a texture from only one location. The viewer moves smoothly relative to the clipmap geometry (no teleporting). The textured geometry must have a reasonable, relatively flat topology.

78 78 g? (1) JPEG PNG (2)S3 S3TC, Texture Compression DirectX DXTC

79 79

80 80 30 million Phong

81 81 Quake III / 10 Flash

82 82 2

83 83

84 84 Thank you for your attention!