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Text File  |  2002-10-03  |  5.7 KB  |  148 lines
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  4. ggggllllEEEEvvvvaaaallllPPPPooooiiiinnnntttt((((3333GGGG))))                OOOOppppeeeennnnGGGGLLLL RRRReeeeffffeeeerrrreeeennnncccceeee                ggggllllEEEEvvvvaaaallllPPPPooooiiiinnnntttt((((3333GGGG))))
  5.  
  6.  
  7.  
  8. NNNNAAAAMMMMEEEE
  9.      ggggllllEEEEvvvvaaaallllPPPPooooiiiinnnntttt1111,,,, ggggllllEEEEvvvvaaaallllPPPPooooiiiinnnntttt2222 - generate and evaluate a single point in a
  10.      mesh
  11.  
  12.  
  13. CCCC SSSSPPPPEEEECCCCIIIIFFFFIIIICCCCAAAATTTTIIIIOOOONNNN
  14.      void ggggllllEEEEvvvvaaaallllPPPPooooiiiinnnntttt1111( GLint _i )
  15.      void ggggllllEEEEvvvvaaaallllPPPPooooiiiinnnntttt2222( GLint _i,
  16.                         GLint _j )
  17.  
  18.  
  19. PPPPAAAARRRRAAAAMMMMEEEETTTTEEEERRRRSSSS
  20.      _i  Specifies the integer value for grid domain variable i.
  21.  
  22.      _j  Specifies the integer value for grid domain variable j (ggggllllEEEEvvvvaaaallllPPPPooooiiiinnnntttt2222
  23.         only).
  24.  
  25. DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
  26.      ggggllllMMMMaaaappppGGGGrrrriiiidddd and ggggllllEEEEvvvvaaaallllMMMMeeeesssshhhh are used in tandem to efficiently generate and
  27.      evaluate a series of evenly spaced map domain values.  ggggllllEEEEvvvvaaaallllPPPPooooiiiinnnntttt can be
  28.      used to evaluate a single grid point in the same gridspace that is
  29.      traversed by ggggllllEEEEvvvvaaaallllMMMMeeeesssshhhh.  Calling ggggllllEEEEvvvvaaaallllPPPPooooiiiinnnntttt1111 is equivalent to calling
  30.  
  31.  
  32.                          .
  33.           glEvalCoord1( i Wu + u  );
  34.                                   1
  35.  
  36.      where
  37.  
  38.           Wu = (u -u )/n
  39.                    2  1
  40.  
  41.  
  42.      and n, u , and u  are the arguments to the most recent ggggllllMMMMaaaappppGGGGrrrriiiidddd1111
  43.              1       2
  44.      command.  The one absolute numeric requirement is that if i = n, then the
  45.                           .
  46.      value computed from i Wu + u  is exactly u .
  47.                                    1             2
  48.  
  49.      In the two-dimensional case, ggggllllEEEEvvvvaaaallllPPPPooooiiiinnnntttt2222, let
  50.  
  51.           Wu = (u -u )/n
  52.                    2  1
  53.  
  54.           Wv = (v -v )/m,
  55.                    2  1
  56.  
  57.      where n, u , u , m, v , and v  are the arguments to the most recent
  58.                1   2      1       2
  59.      ggggllllMMMMaaaappppGGGGrrrriiiidddd2222 command.  Then the ggggllllEEEEvvvvaaaallllPPPPooooiiiinnnntttt2222 command is equivalent to
  60.      calling
  61.  
  62.  
  63.                          .            .
  64.           glEvalCoord2( i Wu + u , j Wv + v  );
  65.                                   1            1
  66.  
  67.      The only absolute numeric requirements are that if i = n, then the value
  68.                     .
  69.      computed from i Wu + u  is exactly u , and if j = m, then the value
  70.                              1             2
  71.                     .
  72.      computed from i Wv + v  is exactly v .
  73.                              1             2
  74.  
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  77.  
  78.                                                                         PPPPaaaaggggeeee 1111
  79.  
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  85. ggggllllEEEEvvvvaaaallllPPPPooooiiiinnnntttt((((3333GGGG))))                OOOOppppeeeennnnGGGGLLLL RRRReeeeffffeeeerrrreeeennnncccceeee                ggggllllEEEEvvvvaaaallllPPPPooooiiiinnnntttt((((3333GGGG))))
  86.  
  87.  
  88.  
  89. AAAASSSSSSSSOOOOCCCCIIIIAAAATTTTEEEEDDDD GGGGEEEETTTTSSSS
  90.      ggggllllGGGGeeeetttt with argument GGGGLLLL____MMMMAAAAPPPP1111____GGGGRRRRIIIIDDDD____DDDDOOOOMMMMAAAAIIIINNNN
  91.      ggggllllGGGGeeeetttt with argument GGGGLLLL____MMMMAAAAPPPP2222____GGGGRRRRIIIIDDDD____DDDDOOOOMMMMAAAAIIIINNNN
  92.      ggggllllGGGGeeeetttt with argument GGGGLLLL____MMMMAAAAPPPP1111____GGGGRRRRIIIIDDDD____SSSSEEEEGGGGMMMMEEEENNNNTTTTSSSS
  93.      ggggllllGGGGeeeetttt with argument GGGGLLLL____MMMMAAAAPPPP2222____GGGGRRRRIIIIDDDD____SSSSEEEEGGGGMMMMEEEENNNNTTTTSSSS
  94.  
  95.  
  96. MMMMAAAACCCCHHHHIIIINNNNEEEE DDDDEEEEPPPPEEEENNNNDDDDEEEENNNNCCCCIIIIEEEESSSS
  97.      RRRReeeeaaaalllliiiittttyyyyEEEEnnnnggggiiiinnnneeee, RRRReeeeaaaalllliiiittttyyyyEEEEnnnnggggiiiinnnneeee2222, and VVVVTTTTXXXX systems do not handle 1D maps for
  98.      colors correctly.
  99.  
  100.  
  101. SSSSEEEEEEEE AAAALLLLSSSSOOOO
  102.      ggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd, ggggllllEEEEvvvvaaaallllMMMMeeeesssshhhh, ggggllllMMMMaaaapppp1111, ggggllllMMMMaaaapppp2222, ggggllllMMMMaaaappppGGGGrrrriiiidddd
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  144.                                                                         PPPPaaaaggggeeee 2222
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