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Text File  |  2002-10-03  |  5.3 KB  |  135 lines
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  4. ggggllllPPPPiiiixxxxeeeellllZZZZoooooooommmm((((3333GGGG))))                OOOOppppeeeennnnGGGGLLLL RRRReeeeffffeeeerrrreeeennnncccceeee                ggggllllPPPPiiiixxxxeeeellllZZZZoooooooommmm((((3333GGGG))))
  5.  
  6.  
  7.  
  8. NNNNAAAAMMMMEEEE
  9.      ggggllllPPPPiiiixxxxeeeellllZZZZoooooooommmm - specify the pixel zoom factors
  10.  
  11.  
  12. CCCC SSSSPPPPEEEECCCCIIIIFFFFIIIICCCCAAAATTTTIIIIOOOONNNN
  13.      void ggggllllPPPPiiiixxxxeeeellllZZZZoooooooommmm( GLfloat _x_f_a_c_t_o_r,
  14.                        GLfloat _y_f_a_c_t_o_r )
  15.  
  16.  
  17. PPPPAAAARRRRAAAAMMMMEEEETTTTEEEERRRRSSSS
  18.      _x_f_a_c_t_o_r, _y_f_a_c_t_o_r Specify the x and y zoom factors for pixel write
  19.                       operations.
  20.  
  21. DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
  22.      ggggllllPPPPiiiixxxxeeeellllZZZZoooooooommmm specifies values for the x and y zoom factors.  During the
  23.      execution of ggggllllDDDDrrrraaaawwwwPPPPiiiixxxxeeeellllssss or ggggllllCCCCooooppppyyyyPPPPiiiixxxxeeeellllssss, if (xr, yr) is the current
  24.      raster position, and a given element is in the mth row and nth column of
  25.      the pixel rectangle, then pixels whose centers are in the rectangle with
  26.      corners at
  27.  
  28.                                 .               .
  29.                          (xr + n xfactor, yr + m yfactor)
  30.  
  31.                                 .                   .
  32.                      (xr + (n+1) xfactor, yr + (m+1) yfactor)
  33.  
  34.      are candidates for replacement.  Any pixel whose center lies on the
  35.      bottom or left edge of this rectangular region is also modified.
  36.  
  37.      Pixel zoom factors are not limited to positive values.  Negative zoom
  38.      factors reflect the resulting image about the current raster position.
  39.  
  40. EEEERRRRRRRROOOORRRRSSSS
  41.      GGGGLLLL____IIIINNNNVVVVAAAALLLLIIIIDDDD____OOOOPPPPEEEERRRRAAAATTTTIIIIOOOONNNN is generated if ggggllllPPPPiiiixxxxeeeellllZZZZoooooooommmm is executed between the
  42.      execution of ggggllllBBBBeeeeggggiiiinnnn and the corresponding execution of ggggllllEEEEnnnndddd.
  43.  
  44. AAAASSSSSSSSOOOOCCCCIIIIAAAATTTTEEEEDDDD GGGGEEEETTTTSSSS
  45.      ggggllllGGGGeeeetttt with argument GGGGLLLL____ZZZZOOOOOOOOMMMM____XXXX
  46.      ggggllllGGGGeeeetttt with argument GGGGLLLL____ZZZZOOOOOOOOMMMM____YYYY
  47.      ggggllllGGGGeeeetttt with argument GGGGLLLL____IIIINNNNTTTTEEEERRRRLLLLAAAACCCCEEEE____SSSSGGGGIIIIXXXX
  48.  
  49.  
  50. MMMMAAAACCCCHHHHIIIINNNNEEEE DDDDEEEEPPPPEEEENNNNDDDDEEEENNNNCCCCIIIIEEEESSSS
  51.      The SSSSGGGGIIIIXXXX____iiiinnnntttteeeerrrrllllaaaacccceeee extension is supported only on IIIInnnnffffiiiinnnniiiitttteeeeRRRReeeeaaaalllliiiittttyyyy
  52.      systems, on RRRReeeeaaaalllliiiittttyyyyEEEEnnnnggggiiiinnnneeee, RRRReeeeaaaalllliiiittttyyyyEEEEnnnnggggiiiinnnneeee2222, and VVVVTTTTXXXX systems, on OOOOccccttttaaaannnneeee2222
  53.      VVVVPPPPrrrroooo systems, and on OOOO2222 systems.
  54.  
  55.      On IIIInnnnffffiiiinnnniiiitttteeeeRRRReeeeaaaalllliiiittttyyyy systems, the absolute values of the zoom factors must
  56.      be strictly less than 128.  If not, they are clamped and GGGGLLLL____IIIINNNNVVVVAAAALLLLIIIIDDDD____VVVVAAAALLLLUUUUEEEE
  57.      is generated.
  58.  
  59.      Pixel zoom factors are snapped to fixed point precision on OOOO2222 systems,
  60.      IIIInnnnddddyyyy and XXXXLLLL systems, XXXXSSSS, XXXXZZZZ, EEEEllllaaaannnn, and EEEExxxxttttrrrreeeemmmmeeee systems.  ggggllllGGGGeeeetttt will
  61.      return these values.
  62.  
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  64.  
  65.                                                                         PPPPaaaaggggeeee 1111
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  72. ggggllllPPPPiiiixxxxeeeellllZZZZoooooooommmm((((3333GGGG))))                OOOOppppeeeennnnGGGGLLLL RRRReeeeffffeeeerrrreeeennnncccceeee                ggggllllPPPPiiiixxxxeeeellllZZZZoooooooommmm((((3333GGGG))))
  73.  
  74.  
  75.  
  76. SSSSEEEEEEEE AAAALLLLSSSSOOOO
  77.      ggggllllCCCCooooppppyyyyPPPPiiiixxxxeeeellllssss, ggggllllEEEEnnnnaaaabbbblllleeee, ggggllllDDDDrrrraaaawwwwPPPPiiiixxxxeeeellllssss.
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  131.                                                                         PPPPaaaaggggeeee 2222
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