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Text File  |  2002-10-03  |  5.6 KB  |  133 lines
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  4. ggggllllDDDDeeeepppptttthhhhFFFFuuuunnnncccc((((3333GGGG))))                OOOOppppeeeennnnGGGGLLLL RRRReeeeffffeeeerrrreeeennnncccceeee                ggggllllDDDDeeeepppptttthhhhFFFFuuuunnnncccc((((3333GGGG))))
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  8. NNNNAAAAMMMMEEEE
  9.      ggggllllDDDDeeeepppptttthhhhFFFFuuuunnnncccc - specify the value used for depth buffer comparisons
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  12. CCCC SSSSPPPPEEEECCCCIIIIFFFFIIIICCCCAAAATTTTIIIIOOOONNNN
  13.      void ggggllllDDDDeeeepppptttthhhhFFFFuuuunnnncccc( GLenum _f_u_n_c )
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  16. PPPPAAAARRRRAAAAMMMMEEEETTTTEEEERRRRSSSS
  17.      _f_u_n_c  Specifies the depth comparison function.  Symbolic constants
  18.            GGGGLLLL____NNNNEEEEVVVVEEEERRRR, GGGGLLLL____LLLLEEEESSSSSSSS, GGGGLLLL____EEEEQQQQUUUUAAAALLLL, GGGGLLLL____LLLLEEEEQQQQUUUUAAAALLLL, GGGGLLLL____GGGGRRRREEEEAAAATTTTEEEERRRR, GGGGLLLL____NNNNOOOOTTTTEEEEQQQQUUUUAAAALLLL,
  19.            GGGGLLLL____GGGGEEEEQQQQUUUUAAAALLLL, and GGGGLLLL____AAAALLLLWWWWAAAAYYYYSSSS are accepted.  The initial value is
  20.            GGGGLLLL____LLLLEEEESSSSSSSS.
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  22. DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
  23.      ggggllllDDDDeeeepppptttthhhhFFFFuuuunnnncccc specifies the function used to compare each incoming pixel
  24.      depth value with the depth value present in the depth buffer.  The
  25.      comparison is performed only if depth testing is enabled.  (See ggggllllEEEEnnnnaaaabbbblllleeee
  26.      and ggggllllDDDDiiiissssaaaabbbblllleeee of GGGGLLLL____DDDDEEEEPPPPTTTTHHHH____TTTTEEEESSSSTTTT.)
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  28.      _f_u_n_c specifies the conditions under which the pixel will be drawn.  The
  29.      comparison functions are as follows:
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  31.      GGGGLLLL____NNNNEEEEVVVVEEEERRRR        Never passes.
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  33.      GGGGLLLL____LLLLEEEESSSSSSSS         Passes if the incoming depth value is less than the
  34.                      stored depth value.
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  36.      GGGGLLLL____EEEEQQQQUUUUAAAALLLL        Passes if the incoming depth value is equal to the stored
  37.                      depth value.
  38.  
  39.      GGGGLLLL____LLLLEEEEQQQQUUUUAAAALLLL       Passes if the incoming depth value is less than or equal
  40.                      to the stored depth value.
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  42.      GGGGLLLL____GGGGRRRREEEEAAAATTTTEEEERRRR      Passes if the incoming depth value is greater than the
  43.                      stored depth value.
  44.  
  45.      GGGGLLLL____NNNNOOOOTTTTEEEEQQQQUUUUAAAALLLL     Passes if the incoming depth value is not equal to the
  46.                      stored depth value.
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  48.      GGGGLLLL____GGGGEEEEQQQQUUUUAAAALLLL       Passes if the incoming depth value is greater than or
  49.                      equal to the stored depth value.
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  51.      GGGGLLLL____AAAALLLLWWWWAAAAYYYYSSSS       Always passes.
  52.  
  53.      The initial value of _f_u_n_c is GGGGLLLL____LLLLEEEESSSSSSSS.  Initially, depth testing is
  54.      disabled.  Even if the depth buffer exists and the depth mask is non-
  55.      zero, the depth buffer is not updated if the depth test is disabled.
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  63.                                                                         PPPPaaaaggggeeee 1111
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  70. ggggllllDDDDeeeepppptttthhhhFFFFuuuunnnncccc((((3333GGGG))))                OOOOppppeeeennnnGGGGLLLL RRRReeeeffffeeeerrrreeeennnncccceeee                ggggllllDDDDeeeepppptttthhhhFFFFuuuunnnncccc((((3333GGGG))))
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  74. ERRORS
  75.      GGGGLLLL____IIIINNNNVVVVAAAALLLLIIIIDDDD____EEEENNNNUUUUMMMM is generated if _f_u_n_c is not an accepted value.
  76.  
  77.      GGGGLLLL____IIIINNNNVVVVAAAALLLLIIIIDDDD____OOOOPPPPEEEERRRRAAAATTTTIIIIOOOONNNN is generated if ggggllllDDDDeeeepppptttthhhhFFFFuuuunnnncccc is executed between the
  78.      execution of ggggllllBBBBeeeeggggiiiinnnn and the corresponding execution of ggggllllEEEEnnnndddd.
  79.  
  80. AAAASSSSSSSSOOOOCCCCIIIIAAAATTTTEEEEDDDD GGGGEEEETTTTSSSS
  81.      ggggllllGGGGeeeetttt with argument GGGGLLLL____DDDDEEEEPPPPTTTTHHHH____FFFFUUUUNNNNCCCC
  82.      ggggllllIIIIssssEEEEnnnnaaaabbbblllleeeedddd with argument GGGGLLLL____DDDDEEEEPPPPTTTTHHHH____TTTTEEEESSSSTTTT
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  85. SSSSEEEEEEEE AAAALLLLSSSSOOOO
  86.      ggggllllDDDDeeeepppptttthhhhRRRRaaaannnnggggeeee, ggggllllEEEEnnnnaaaabbbblllleeee, ggggllllPPPPoooollllyyyyggggoooonnnnOOOOffffffffsssseeeetttt
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  129.                                                                         PPPPaaaaggggeeee 2222
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