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/ IRIX Base Documentation 2001 May / SGI IRIX Base Documentation 2001 May.iso / usr / share / catman / g_man / cat3 / OpenGL / glevalcoord.z / glevalcoord
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Text File  |  2001-04-17  |  16.9 KB  |  205 lines
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  4. ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd((((3333GGGG))))                OOOOppppeeeennnnGGGGLLLL RRRReeeeffffeeeerrrreeeennnncccceeee                ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd((((3333GGGG))))
  5.  
  6.  
  7.  
  8. NNNNAAAAMMMMEEEE
  9.      ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd1111dddd,,,, ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd1111ffff,,,, ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd2222dddd,,,, ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd2222ffff,,,,
  10.      ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd1111ddddvvvv,,,, ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd1111ffffvvvv,,,, ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd2222ddddvvvv,,,, ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd2222ffffvvvv - evaluate
  11.      enabled one- and two-dimensional maps
  12.  
  13.  
  14. CCCC SSSSPPPPEEEECCCCIIIIFFFFIIIICCCCAAAATTTTIIIIOOOONNNN
  15.      void ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd1111dddd( GLdouble _u )
  16.      void ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd1111ffff( GLfloat _u )
  17.      void ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd2222dddd( GLdouble _u,
  18.                          GLdouble _v )
  19.      void ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd2222ffff( GLfloat _u,
  20.                          GLfloat _v )
  21.  
  22.  
  23. PPPPAAAARRRRAAAAMMMMEEEETTTTEEEERRRRSSSS
  24.      _u  Specifies a value that is the domain coordinate u to the basis
  25.         function defined in a previous ggggllllMMMMaaaapppp1111 or ggggllllMMMMaaaapppp2222 command.
  26.  
  27.      _v  Specifies a value that is the domain coordinate v to the basis
  28.         function defined in a previous ggggllllMMMMaaaapppp2222 command.  This argument is not
  29.         present in a ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd1111 command.
  30.  
  31. CCCC SSSSPPPPEEEECCCCIIIIFFFFIIIICCCCAAAATTTTIIIIOOOONNNN
  32.      void ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd1111ddddvvvv( const GLdouble *_u )
  33.      void ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd1111ffffvvvv( const GLfloat *_u )
  34.      void ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd2222ddddvvvv( const GLdouble *_u )
  35.      void ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd2222ffffvvvv( const GLfloat *_u )
  36.  
  37.  
  38. PPPPAAAARRRRAAAAMMMMEEEETTTTEEEERRRRSSSS
  39.      _u    Specifies a pointer to an array containing either one or two domain
  40.           coordinates.  The first coordinate is u.  The second coordinate is
  41.           v, which is present only in ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd2222 versions.
  42.  
  43. DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
  44.      ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd1111 evaluates enabled one-dimensional maps at argument _u.
  45.      ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd2222 does the same for two-dimensional maps using two domain
  46.      values, _u and _v.  To define a map, call ggggllllMMMMaaaapppp1111 and ggggllllMMMMaaaapppp2222; to enable and
  47.      disable it, call ggggllllEEEEnnnnaaaabbbblllleeee and ggggllllDDDDiiiissssaaaabbbblllleeee.
  48.  
  49.      When one of the ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd commands is issued, all currently enabled
  50.      maps of the indicated dimension are evaluated.  Then, for each enabled
  51.      map, it is as if the corresponding GL command had been issued with the
  52.      computed value.  That is, if GGGGLLLL____MMMMAAAAPPPP1111____IIIINNNNDDDDEEEEXXXX or GGGGLLLL____MMMMAAAAPPPP2222____IIIINNNNDDDDEEEEXXXX is enabled, a
  53.      ggggllllIIIInnnnddddeeeexxxx command is simulated.  If GGGGLLLL____MMMMAAAAPPPP1111____CCCCOOOOLLLLOOOORRRR____4444 or GGGGLLLL____MMMMAAAAPPPP2222____CCCCOOOOLLLLOOOORRRR____4444 is
  54.      enabled, a ggggllllCCCCoooolllloooorrrr command is simulated.  If GGGGLLLL____MMMMAAAAPPPP1111____NNNNOOOORRRRMMMMAAAALLLL or
  55.      GGGGLLLL____MMMMAAAAPPPP2222____NNNNOOOORRRRMMMMAAAALLLL is enabled, a normal vector is produced, and if any of
  56.      GGGGLLLL____MMMMAAAAPPPP1111____TTTTEEEEXXXXTTTTUUUURRRREEEE____CCCCOOOOOOOORRRRDDDD____1111, GGGGLLLL____MMMMAAAAPPPP1111____TTTTEEEEXXXXTTTTUUUURRRREEEE____CCCCOOOOOOOORRRRDDDD____2222,
  57.      GGGGLLLL____MMMMAAAAPPPP1111____TTTTEEEEXXXXTTTTUUUURRRREEEE____CCCCOOOOOOOORRRRDDDD____3333, GGGGLLLL____MMMMAAAAPPPP1111____TTTTEEEEXXXXTTTTUUUURRRREEEE____CCCCOOOOOOOORRRRDDDD____4444,
  58.      GGGGLLLL____MMMMAAAAPPPP2222____TTTTEEEEXXXXTTTTUUUURRRREEEE____CCCCOOOOOOOORRRRDDDD____1111, GGGGLLLL____MMMMAAAAPPPP2222____TTTTEEEEXXXXTTTTUUUURRRREEEE____CCCCOOOOOOOORRRRDDDD____2222,
  59.      GGGGLLLL____MMMMAAAAPPPP2222____TTTTEEEEXXXXTTTTUUUURRRREEEE____CCCCOOOOOOOORRRRDDDD____3333, or GGGGLLLL____MMMMAAAAPPPP2222____TTTTEEEEXXXXTTTTUUUURRRREEEE____CCCCOOOOOOOORRRRDDDD____4444 is enabled, then an
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  63.                                                                         PPPPaaaaggggeeee 1111
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  69.  
  70. ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd((((3333GGGG))))                OOOOppppeeeennnnGGGGLLLL RRRReeeeffffeeeerrrreeeennnncccceeee                ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd((((3333GGGG))))
  71.  
  72.  
  73.  
  74.      appropriate ggggllllTTTTeeeexxxxCCCCoooooooorrrrdddd command is simulated.
  75.  
  76.      For color, color index, normal, and texture coordinates the GL uses
  77.      evaluated values instead of current values for those evaluations that are
  78.      enabled, and current values otherwise, However, the evaluated values do
  79.      not update the current values.  Thus, if ggggllllVVVVeeeerrrrtttteeeexxxx commands are
  80.      interspersed with ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd commands, the color, normal, and texture
  81.      coordinates associated with the ggggllllVVVVeeeerrrrtttteeeexxxx commands are not affected by the
  82.      values generated by the ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd commands, but only by the most recent
  83.      ggggllllCCCCoooolllloooorrrr, ggggllllIIIInnnnddddeeeexxxx, ggggllllNNNNoooorrrrmmmmaaaallll, and ggggllllTTTTeeeexxxxCCCCoooooooorrrrdddd commands.
  84.  
  85.      No commands are issued for maps that are not enabled.  If more than one
  86.      texture evaluation is enabled for a particular dimension (for example,
  87.      GGGGLLLL____MMMMAAAAPPPP2222____TTTTEEEEXXXXTTTTUUUURRRREEEE____CCCCOOOOOOOORRRRDDDD____1111 and GGGGLLLL____MMMMAAAAPPPP2222____TTTTEEEEXXXXTTTTUUUURRRREEEE____CCCCOOOOOOOORRRRDDDD____2222), then only the
  88.      evaluation of the map that produces the larger number of coordinates (in
  89.      this case, GGGGLLLL____MMMMAAAAPPPP2222____TTTTEEEEXXXXTTTTUUUURRRREEEE____CCCCOOOOOOOORRRRDDDD____2222) is carried out.  GGGGLLLL____MMMMAAAAPPPP1111____VVVVEEEERRRRTTTTEEEEXXXX____4444
  90.      overrides GGGGLLLL____MMMMAAAAPPPP1111____VVVVEEEERRRRTTTTEEEEXXXX____3333, and GGGGLLLL____MMMMAAAAPPPP2222____VVVVEEEERRRRTTTTEEEEXXXX____4444 overrides
  91.      GGGGLLLL____MMMMAAAAPPPP2222____VVVVEEEERRRRTTTTEEEEXXXX____3333, in the same manner.  If neither a three- nor a four-
  92.      component vertex map is enabled for the specified dimension, the
  93.      ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd command is ignored.
  94.  
  95.      If you have enabled automatic normal generation, by calling ggggllllEEEEnnnnaaaabbbblllleeee with
  96.      argument GGGGLLLL____AAAAUUUUTTTTOOOO____NNNNOOOORRRRMMMMAAAALLLL, ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd2222 generates surface normals
  97.      analytically, regardless of the contents or enabling of the
  98.      GGGGLLLL____MMMMAAAAPPPP2222____NNNNOOOORRRRMMMMAAAALLLL map.  Let
  99.  
  100.                                             ]p__       ]p__
  101.                                     m =        x
  102.                                         ]u     ]v
  103.  
  104.  
  105.      Then the generated normal n is
  106.                                               m_____
  107.                                      n =
  108.                                          ||m||
  109.  
  110.  
  111.      If automatic normal generation is disabled, the corresponding normal map
  112.      GGGGLLLL____MMMMAAAAPPPP2222____NNNNOOOORRRRMMMMAAAALLLL, if enabled, is used to produce a normal.  If neither
  113.      automatic normal generation nor a normal map is enabled, no normal is
  114.      generated for ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd2222 commands.
  115.  
  116. AAAASSSSSSSSOOOOCCCCIIIIAAAATTTTEEEEDDDD GGGGEEEETTTTSSSS
  117.      ggggllllIIIIssssEEEEnnnnaaaabbbblllleeeedddd with argument GGGGLLLL____MMMMAAAAPPPP1111____VVVVEEEERRRRTTTTEEEEXXXX____3333
  118.      ggggllllIIIIssssEEEEnnnnaaaabbbblllleeeedddd with argument GGGGLLLL____MMMMAAAAPPPP1111____VVVVEEEERRRRTTTTEEEEXXXX____4444
  119.      ggggllllIIIIssssEEEEnnnnaaaabbbblllleeeedddd with argument GGGGLLLL____MMMMAAAAPPPP1111____IIIINNNNDDDDEEEEXXXX
  120.      ggggllllIIIIssssEEEEnnnnaaaabbbblllleeeedddd with argument GGGGLLLL____MMMMAAAAPPPP1111____CCCCOOOOLLLLOOOORRRR____4444
  121.      ggggllllIIIIssssEEEEnnnnaaaabbbblllleeeedddd with argument GGGGLLLL____MMMMAAAAPPPP1111____NNNNOOOORRRRMMMMAAAALLLL
  122.      ggggllllIIIIssssEEEEnnnnaaaabbbblllleeeedddd with argument GGGGLLLL____MMMMAAAAPPPP1111____TTTTEEEEXXXXTTTTUUUURRRREEEE____CCCCOOOOOOOORRRRDDDD____1111
  123.      ggggllllIIIIssssEEEEnnnnaaaabbbblllleeeedddd with argument GGGGLLLL____MMMMAAAAPPPP1111____TTTTEEEEXXXXTTTTUUUURRRREEEE____CCCCOOOOOOOORRRRDDDD____2222
  124.      ggggllllIIIIssssEEEEnnnnaaaabbbblllleeeedddd with argument GGGGLLLL____MMMMAAAAPPPP1111____TTTTEEEEXXXXTTTTUUUURRRREEEE____CCCCOOOOOOOORRRRDDDD____3333
  125.      ggggllllIIIIssssEEEEnnnnaaaabbbblllleeeedddd with argument GGGGLLLL____MMMMAAAAPPPP1111____TTTTEEEEXXXXTTTTUUUURRRREEEE____CCCCOOOOOOOORRRRDDDD____4444
  126.      ggggllllIIIIssssEEEEnnnnaaaabbbblllleeeedddd with argument GGGGLLLL____MMMMAAAAPPPP2222____VVVVEEEERRRRTTTTEEEEXXXX____3333
  127.      ggggllllIIIIssssEEEEnnnnaaaabbbblllleeeedddd with argument GGGGLLLL____MMMMAAAAPPPP2222____VVVVEEEERRRRTTTTEEEEXXXX____4444
  128.      ggggllllIIIIssssEEEEnnnnaaaabbbblllleeeedddd with argument GGGGLLLL____MMMMAAAAPPPP2222____IIIINNNNDDDDEEEEXXXX
  129.      ggggllllIIIIssssEEEEnnnnaaaabbbblllleeeedddd with argument GGGGLLLL____MMMMAAAAPPPP2222____CCCCOOOOLLLLOOOORRRR____4444
  130.      ggggllllIIIIssssEEEEnnnnaaaabbbblllleeeedddd with argument GGGGLLLL____MMMMAAAAPPPP2222____NNNNOOOORRRRMMMMAAAALLLL
  131.      ggggllllIIIIssssEEEEnnnnaaaabbbblllleeeedddd with argument GGGGLLLL____MMMMAAAAPPPP2222____TTTTEEEEXXXXTTTTUUUURRRREEEE____CCCCOOOOOOOORRRRDDDD____1111
  132.  
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  134.  
  135.                                                                         PPPPaaaaggggeeee 2222
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  141.  
  142. ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd((((3333GGGG))))                OOOOppppeeeennnnGGGGLLLL RRRReeeeffffeeeerrrreeeennnncccceeee                ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd((((3333GGGG))))
  143.  
  144.  
  145.  
  146.      ggggllllIIIIssssEEEEnnnnaaaabbbblllleeeedddd with argument GGGGLLLL____MMMMAAAAPPPP2222____TTTTEEEEXXXXTTTTUUUURRRREEEE____CCCCOOOOOOOORRRRDDDD____2222
  147.      ggggllllIIIIssssEEEEnnnnaaaabbbblllleeeedddd with argument GGGGLLLL____MMMMAAAAPPPP2222____TTTTEEEEXXXXTTTTUUUURRRREEEE____CCCCOOOOOOOORRRRDDDD____3333
  148.      ggggllllIIIIssssEEEEnnnnaaaabbbblllleeeedddd with argument GGGGLLLL____MMMMAAAAPPPP2222____TTTTEEEEXXXXTTTTUUUURRRREEEE____CCCCOOOOOOOORRRRDDDD____4444
  149.      ggggllllIIIIssssEEEEnnnnaaaabbbblllleeeedddd with argument GGGGLLLL____AAAAUUUUTTTTOOOO____NNNNOOOORRRRMMMMAAAALLLL
  150.      ggggllllGGGGeeeettttMMMMaaaapppp
  151.  
  152.  
  153. MMMMAAAACCCCHHHHIIIINNNNEEEE DDDDEEEEPPPPEEEENNNNDDDDEEEENNNNCCCCIIIIEEEESSSS
  154.      RRRReeeeaaaalllliiiittttyyyyEEEEnnnnggggiiiinnnneeee, RRRReeeeaaaalllliiiittttyyyyEEEEnnnnggggiiiinnnneeee2222, and VVVVTTTTXXXX systems do not handle 1D maps for
  155.      colors correctly.
  156.  
  157.  
  158. SSSSEEEEEEEE AAAALLLLSSSSOOOO
  159.      ggggllllBBBBeeeeggggiiiinnnn, ggggllllCCCCoooolllloooorrrr, ggggllllEEEEnnnnaaaabbbblllleeee, ggggllllEEEEvvvvaaaallllMMMMeeeesssshhhh, ggggllllEEEEvvvvaaaallllPPPPooooiiiinnnntttt, ggggllllIIIInnnnddddeeeexxxx, ggggllllMMMMaaaapppp1111,
  160.      ggggllllMMMMaaaapppp2222, ggggllllMMMMaaaappppGGGGrrrriiiidddd, ggggllllNNNNoooorrrrmmmmaaaallll, ggggllllTTTTeeeexxxxCCCCoooooooorrrrdddd, ggggllllVVVVeeeerrrrtttteeeexxxx
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  201.                                                                         PPPPaaaaggggeeee 3333
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