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|00000000| 5c 63 68 61 70 74 65 72 | 20 7b 54 65 78 74 75 72 |\chapter| {Textur|
|00000010| 69 6e 67 7d 0a 0a 54 65 | 78 74 75 72 65 73 20 61 |ing}..Te|xtures a|
|00000020| 72 65 20 75 73 65 64 20 | 74 6f 20 6d 6f 64 69 66 |re used |to modif|
|00000030| 79 20 74 68 65 20 61 70 | 70 65 61 72 61 6e 63 65 |y the ap|pearance|
|00000040| 20 6f 66 20 61 6e 20 6f | 62 6a 65 63 74 20 74 68 | of an o|bject th|
|00000050| 72 6f 75 67 68 20 74 68 | 65 0a 75 73 65 20 6f 66 |rough th|e.use of|
|00000060| 20 70 72 6f 63 65 64 75 | 72 61 6c 20 66 75 6e 63 | procedu|ral func|
|00000070| 74 69 6f 6e 73 2e 20 20 | 41 20 74 65 78 74 75 72 |tions.  |A textur|
|00000080| 65 20 6d 61 79 20 6d 6f | 64 69 66 79 20 61 6e 79 |e may mo|dify any|
|00000090| 20 73 75 72 66 61 63 65 | 20 63 68 61 72 61 63 74 | surface| charact|
|000000a0| 65 72 69 73 74 69 63 2c | 0a 73 75 63 68 20 61 73 |eristic,|.such as|
|000000b0| 20 64 69 66 66 75 73 65 | 20 63 6f 6c 6f 72 2c 20 | diffuse| color, |
|000000c0| 72 65 66 6c 65 63 74 69 | 76 69 74 79 2c 20 6f 72 |reflecti|vity, or|
|000000d0| 20 74 72 61 6e 73 70 61 | 72 65 6e 63 79 2c 20 6f | transpa|rency, o|
|000000e0| 72 20 69 74 20 6d 61 79 | 20 0a 6d 6f 64 69 66 79 |r it may| .modify|
|000000f0| 20 74 68 65 20 73 75 72 | 66 61 63 65 20 6e 6f 72 | the sur|face nor|
|00000100| 6d 61 6c 20 28 60 60 62 | 75 6d 70 20 6d 61 70 70 |mal (``b|ump mapp|
|00000110| 69 6e 67 27 27 29 20 69 | 6e 20 6f 72 64 65 72 20 |ing'') i|n order |
|00000120| 74 6f 20 67 69 76 65 20 | 74 68 65 0a 61 70 70 65 |to give |the.appe|
|00000130| 61 72 61 6e 63 65 20 6f | 66 20 61 20 72 6f 75 67 |arance o|f a roug|
|00000140| 68 20 73 75 72 66 61 63 | 65 2e 0a 0a 41 6e 79 20 |h surfac|e...Any |
|00000150| 6e 75 6d 62 65 72 20 6f | 66 20 74 65 78 74 75 72 |number o|f textur|
|00000160| 65 73 20 6d 61 79 20 62 | 65 20 61 73 73 6f 63 69 |es may b|e associ|
|00000170| 61 74 65 64 20 77 69 74 | 68 20 61 6e 20 6f 62 6a |ated wit|h an obj|
|00000180| 65 63 74 2e 20 20 49 66 | 20 6d 6f 72 65 20 74 68 |ect.  If| more th|
|00000190| 61 6e 0a 6f 6e 65 20 74 | 65 78 74 75 72 65 20 69 |an.one t|exture i|
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|000001b0| 79 20 61 72 65 20 61 70 | 70 6c 69 65 64 20 69 6e |y are ap|plied in|
|000001c0| 20 74 68 65 20 6f 72 64 | 65 72 20 67 69 76 65 6e | the ord|er given|
|000001d0| 2e 20 20 54 68 69 73 20 | 61 6c 6c 6f 77 73 0a 6f |.  This |allows.o|
|000001e0| 6e 65 20 74 6f 20 63 6f | 6d 70 6f 73 65 20 74 65 |ne to co|mpose te|
|000001f0| 78 74 75 72 69 6e 67 20 | 66 75 6e 63 74 69 6f 6e |xturing |function|
|00000200| 73 20 61 6e 64 20 63 72 | 65 61 74 65 2c 20 66 6f |s and cr|eate, fo|
|00000210| 72 20 65 78 61 6d 70 6c | 65 0a 61 20 74 69 6c 65 |r exampl|e.a tile|
|00000220| 64 20 6d 61 72 62 6c 65 | 20 67 72 6f 75 6e 64 20 |d marble| ground |
|00000230| 70 6c 61 6e 65 20 75 73 | 69 6e 67 20 74 68 65 20 |plane us|ing the |
|00000240| 7b 5c 65 6d 20 63 68 65 | 63 6b 65 72 7d 20 61 6e |{\em che|cker} an|
|00000250| 64 20 7b 5c 65 6d 20 6d | 61 72 62 6c 65 7d 0a 74 |d {\em m|arble}.t|
|00000260| 65 78 74 75 72 65 73 2e | 0a 0a 54 65 78 74 75 72 |extures.|..Textur|
|00000270| 65 73 20 61 72 65 20 61 | 73 73 6f 63 69 61 74 65 |es are a|ssociate|
|00000280| 64 20 77 69 74 68 20 6f | 62 6a 65 63 74 73 20 62 |d with o|bjects b|
|00000290| 79 20 66 6f 6c 6c 6f 77 | 69 6e 67 20 74 68 65 20 |y follow|ing the |
|000002a0| 6f 62 6a 65 63 74 20 73 | 70 65 63 69 66 69 63 61 |object s|pecifica|
|000002b0| 74 69 6f 6e 0a 62 79 20 | 61 20 6e 75 6d 62 65 72 |tion.by |a number|
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|000002d0| 20 66 6f 72 6d 3a 0a 0a | 5c 62 65 67 69 6e 7b 63 | form:..|\begin{c|
|000002e0| 65 6e 74 65 72 7d 0a 7b | 5c 74 74 20 74 65 78 74 |enter}.{|\tt text|
|000002f0| 75 72 65 7d 20 7b 5c 65 | 6d 20 6e 61 6d 65 7d 20 |ure} {\e|m name} |
|00000300| 24 3c 24 7b 5c 65 6d 20 | 54 65 78 74 75 72 69 6e |$<${\em |Texturin|
|00000310| 67 20 41 72 67 75 6d 65 | 6e 74 73 7d 24 3e 24 20 |g Argume|nts}$>$ |
|00000320| 5b 7b 5c 65 6d 20 54 72 | 61 6e 73 66 6f 72 6d 61 |[{\em Tr|ansforma|
|00000330| 74 69 6f 6e 73 7d 5d 0a | 5c 65 6e 64 7b 63 65 6e |tions}].|\end{cen|
|00000340| 74 65 72 7d 0a 0a 54 72 | 61 6e 73 66 6f 72 6d 61 |ter}..Tr|ansforma|
|00000350| 74 69 6f 6e 73 20 6d 61 | 79 20 62 65 20 61 70 70 |tions ma|y be app|
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|00000380| 20 66 6f 72 20 65 78 61 | 6d 70 6c 65 2c 0a 73 68 | for exa|mple,.sh|
|00000390| 72 69 6e 6b 20 6f 72 20 | 67 72 6f 77 20 66 65 61 |rink or |grow fea|
|000003a0| 74 75 72 65 20 73 69 7a | 65 2c 20 63 68 61 6e 67 |ture siz|e, chang|
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|000003d0| 6e 64 0a 63 68 61 6e 67 | 65 20 74 68 65 20 70 6f |nd.chang|e the po|
|000003e0| 73 69 74 69 6f 6e 20 6f | 66 20 66 65 61 74 75 72 |sition o|f featur|
|000003f0| 65 73 2e 0a 0a 53 65 76 | 65 72 61 6c 20 6f 66 20 |es...Sev|eral of |
|00000400| 74 68 65 20 74 65 78 74 | 75 72 69 6e 67 20 66 75 |the text|uring fu|
|00000410| 6e 63 74 69 6f 6e 73 20 | 74 61 6b 65 20 74 68 65 |nctions |take the|
|00000420| 20 6e 61 6d 65 20 6f 66 | 20 61 20 63 6f 6c 6f 72 | name of| a color|
|00000430| 6d 61 70 20 61 73 20 61 | 6e 0a 61 72 67 75 6d 65 |map as a|n.argume|
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|00000450| 69 73 20 32 35 36 2d 6c | 69 6e 65 20 41 53 43 49 |is 256-l|ine ASCI|
|00000460| 49 20 66 69 6c 65 2c 20 | 77 69 74 68 20 65 61 63 |I file, |with eac|
|00000470| 68 20 6c 69 6e 65 20 63 | 6f 6e 74 61 69 6e 69 6e |h line c|ontainin|
|00000480| 67 0a 74 68 72 65 65 20 | 73 70 61 63 65 2d 73 65 |g.three |space-se|
|00000490| 70 61 72 61 74 65 64 20 | 76 61 6c 75 65 73 20 72 |parated |values r|
|000004a0| 61 6e 67 69 6e 67 20 66 | 72 6f 6d 20 30 20 74 6f |anging f|rom 0 to|
|000004b0| 20 32 35 35 2e 20 20 45 | 61 63 68 20 6c 69 6e 65 | 255.  E|ach line|
|000004c0| 20 67 69 76 65 73 0a 74 | 68 65 20 72 65 64 2c 20 | gives.t|he red, |
|000004d0| 67 72 65 65 6e 2c 20 61 | 6e 64 20 62 6c 75 65 20 |green, a|nd blue |
|000004e0| 76 61 6c 75 65 73 20 66 | 6f 72 20 61 20 73 69 6e |values f|or a sin|
|000004f0| 67 6c 65 20 65 6e 74 72 | 79 20 69 6e 20 74 68 65 |gle entr|y in the|
|00000500| 20 63 6f 6c 6f 72 6d 61 | 70 2e 0a 0a 5c 73 65 63 | colorma|p...\sec|
|00000510| 74 69 6f 6e 20 7b 54 65 | 78 74 75 72 69 6e 67 20 |tion {Te|xturing |
|00000520| 46 75 6e 63 74 69 6f 6e | 73 7d 0a 0a 5c 62 65 67 |Function|s}..\beg|
|00000530| 69 6e 7b 64 65 66 6b 65 | 79 7d 7b 62 6c 6f 74 63 |in{defke|y}{blotc|
|00000540| 68 7d 7b 7b 5c 65 6d 20 | 42 6c 65 6e 64 46 61 63 |h}{{\em |BlendFac|
|00000550| 74 6f 72 20 73 75 72 66 | 61 63 65 7d 7d 0a 50 72 |tor surf|ace}}.Pr|
|00000560| 6f 64 75 63 65 73 20 61 | 20 6d 69 6c 64 6c 79 20 |oduces a| mildly |
|00000570| 69 6e 74 65 72 65 73 74 | 69 6e 67 20 62 6c 6f 74 |interest|ing blot|
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|00000590| 61 63 65 2e 0a 7b 5c 65 | 6d 20 42 6c 65 6e 64 46 |ace..{\e|m BlendF|
|000005a0| 61 63 74 6f 72 7d 20 69 | 73 20 75 73 65 64 20 74 |actor} i|s used t|
|000005b0| 6f 20 63 6f 6e 74 72 6f | 6c 20 74 68 65 20 69 6e |o contro|l the in|
|000005c0| 74 65 72 70 6f 6c 61 74 | 69 6f 6e 20 62 65 74 77 |terpolat|ion betw|
|000005d0| 65 65 6e 0a 74 68 65 20 | 64 65 66 61 75 6c 74 20 |een.the |default |
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|00000660| 72 66 61 63 65 73 2e 20 | 20 48 69 67 68 65 72 20 |rfaces. | Higher |
|00000670| 76 61 6c 75 65 73 20 72 | 65 73 75 6c 74 20 69 6e |values r|esult in|
|00000680| 20 61 20 67 72 65 61 74 | 20 70 6f 72 74 69 6f 6e | a great| portion|
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+--------+-------------------------+-------------------------+--------+--------+