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Text File  |  2002-10-03  |  6.6 KB  |  133 lines
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  4. ffffggggllllPPPPoooollllyyyyggggoooonnnnOOOOffffffffsssseeeetttt((((3333GGGG))))           OOOOppppeeeennnnGGGGLLLL RRRReeeeffffeeeerrrreeeennnncccceeee           ffffggggllllPPPPoooollllyyyyggggoooonnnnOOOOffffffffsssseeeetttt((((3333GGGG))))
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  8. NNNNAAAAMMMMEEEE
  9.      ffffggggllllPPPPoooollllyyyyggggoooonnnnOOOOffffffffsssseeeetttt - set the scale and units used to calculate depth values
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  12. FFFFOOOORRRRTTTTRRRRAAAANNNN SSSSPPPPEEEECCCCIIIIFFFFIIIICCCCAAAATTTTIIIIOOOONNNN
  13.      SUBROUTINE ffffggggllllPPPPoooollllyyyyggggoooonnnnOOOOffffffffsssseeeetttt( REAL*4 _f_a_c_t_o_r,
  14.                                   REAL*4 _u_n_i_t_s )
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  17. PPPPAAAARRRRAAAAMMMMEEEETTTTEEEERRRRSSSS
  18.      _f_a_c_t_o_r  Specifies a scale factor that is used to create a variable depth
  19.              offset for each polygon. The initial value is 0.
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  21.      _u_n_i_t_s   Is multiplied by an implementation-specific value to create a
  22.              constant depth offset. The initial value is 0.
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  24. DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
  25.      When GGGGLLLL____PPPPOOOOLLLLYYYYGGGGOOOONNNN____OOOOFFFFFFFFSSSSEEEETTTT____FFFFIIIILLLLLLLL, GGGGLLLL____PPPPOOOOLLLLYYYYGGGGOOOONNNN____OOOOFFFFFFFFSSSSEEEETTTT____LLLLIIIINNNNEEEE, or
  26.      GGGGLLLL____PPPPOOOOLLLLYYYYGGGGOOOONNNN____OOOOFFFFFFFFSSSSEEEETTTT____PPPPOOOOIIIINNNNTTTT is enabled, each fragment's _d_e_p_t_h value will be
  27.      offset after it is interpolated from the _d_e_p_t_h values of the appropriate
  28.      vertices.  The value of the offset is factor * DZ  +  r * units, where
  29.      DZ  is a measurement of the change in depth relative to the screen area
  30.      of the polygon, and r is the smallest value that is guaranteed to produce
  31.      a resolvable offset for a given implementation.  The offset is added
  32.      before the depth test is performed and before the value is written into
  33.      the depth buffer.
  34.  
  35.      ffffggggllllPPPPoooollllyyyyggggoooonnnnOOOOffffffffsssseeeetttt is useful for rendering hidden-line images, for applying
  36.      decals to surfaces, and for rendering solids with highlighted edges.
  37.  
  38. NNNNOOOOTTTTEEEESSSS
  39.      ffffggggllllPPPPoooollllyyyyggggoooonnnnOOOOffffffffsssseeeetttt is available only if the GL version is 1.1 or greater.
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  41.      ffffggggllllPPPPoooollllyyyyggggoooonnnnOOOOffffffffsssseeeetttt has no effect on depth coordinates placed in the
  42.      feedback buffer.
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  44.      ffffggggllllPPPPoooollllyyyyggggoooonnnnOOOOffffffffsssseeeetttt has no effect on selection.
  45.  
  46. EEEERRRRRRRROOOORRRRSSSS
  47.      GGGGLLLL____IIIINNNNVVVVAAAALLLLIIIIDDDD____OOOOPPPPEEEERRRRAAAATTTTIIIIOOOONNNN is generated if ffffggggllllPPPPoooollllyyyyggggoooonnnnOOOOffffffffsssseeeetttt is executed between
  48.      the execution of ffffggggllllBBBBeeeeggggiiiinnnn and the corresponding execution of ffffggggllllEEEEnnnndddd.
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  63.                                                                         PPPPaaaaggggeeee 1111
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  70. ffffggggllllPPPPoooollllyyyyggggoooonnnnOOOOffffffffsssseeeetttt((((3333GGGG))))           OOOOppppeeeennnnGGGGLLLL RRRReeeeffffeeeerrrreeeennnncccceeee           ffffggggllllPPPPoooollllyyyyggggoooonnnnOOOOffffffffsssseeeetttt((((3333GGGG))))
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  74. AAAASSSSSSSSOOOOCCCCIIIIAAAATTTTEEEEDDDD GGGGEEEETTTTSSSS
  75.      ffffggggllllIIIIssssEEEEnnnnaaaabbbblllleeeedddd with argument GGGGLLLL____PPPPOOOOLLLLYYYYGGGGOOOONNNN____OOOOFFFFFFFFSSSSEEEETTTT____FFFFIIIILLLLLLLL,
  76.      GGGGLLLL____PPPPOOOOLLLLYYYYGGGGOOOONNNN____OOOOFFFFFFFFSSSSEEEETTTT____LLLLIIIINNNNEEEE, or GGGGLLLL____PPPPOOOOLLLLYYYYGGGGOOOONNNN____OOOOFFFFFFFFSSSSEEEETTTT____PPPPOOOOIIIINNNNTTTT.
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  78.      ffffggggllllGGGGeeeetttt with argument GGGGLLLL____PPPPOOOOLLLLYYYYGGGGOOOONNNN____OOOOFFFFFFFFSSSSEEEETTTT____FFFFAAAACCCCTTTTOOOORRRR or GGGGLLLL____PPPPOOOOLLLLYYYYGGGGOOOONNNN____OOOOFFFFFFFFSSSSEEEETTTT____UUUUNNNNIIIITTTTSSSS.
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  80.  
  81. MMMMAAAACCCCHHHHIIIINNNNEEEE DDDDEEEEPPPPEEEENNNNDDDDEEEENNNNCCCCIIIIEEEESSSS
  82.      GGGGLLLL____PPPPOOOOLLLLYYYYGGGGOOOONNNN____OOOOFFFFFFFFSSSSEEEETTTT____LLLLIIIINNNNEEEE and GGGGLLLL____PPPPOOOOLLLLYYYYGGGGOOOONNNN____OOOOFFFFFFFFSSSSEEEETTTT____PPPPOOOOIIIINNNNTTTT are not implemented on
  83.      XS, XZ, Elan, and Extreme, RealityEngine, RealityEngine2, and VTX and
  84.      InfiniteReality systems.
  85.  
  86.  
  87. SSSSEEEEEEEE AAAALLLLSSSSOOOO
  88.      ffffggggllllDDDDeeeepppptttthhhhFFFFuuuunnnncccc, ffffggggllllDDDDiiiissssaaaabbbblllleeee, ffffggggllllEEEEnnnnaaaabbbblllleeee, ffffggggllllGGGGeeeetttt, ffffggggllllIIIIssssEEEEnnnnaaaabbbblllleeeedddd, ffffggggllllLLLLiiiinnnneeeeWWWWiiiiddddtttthhhh,
  89.      ffffggggllllSSSStttteeeennnncccciiiillllOOOOpppp, ffffggggllllTTTTeeeexxxxEEEEnnnnvvvv
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  129.                                                                         PPPPaaaaggggeeee 2222
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