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/ IRIX Base Documentation 2001 May / SGI IRIX Base Documentation 2001 May.iso / usr / share / catman / g_man / cat3 / OpenGL / glscissor.z / glscissor
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Text File  |  2001-04-17  |  4.6 KB  |  133 lines
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  4. ggggllllSSSScccciiiissssssssoooorrrr((((3333GGGG))))                  OOOOppppeeeennnnGGGGLLLL RRRReeeeffffeeeerrrreeeennnncccceeee                  ggggllllSSSScccciiiissssssssoooorrrr((((3333GGGG))))
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  8. NNNNAAAAMMMMEEEE
  9.      ggggllllSSSScccciiiissssssssoooorrrr - define the scissor box
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  12. CCCC SSSSPPPPEEEECCCCIIIIFFFFIIIICCCCAAAATTTTIIIIOOOONNNN
  13.      void ggggllllSSSScccciiiissssssssoooorrrr( GLint _x,
  14.                      GLint _y,
  15.                      GLsizei _w_i_d_t_h,
  16.                      GLsizei _h_e_i_g_h_t )
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  19. PPPPAAAARRRRAAAAMMMMEEEETTTTEEEERRRRSSSS
  20.      _x, _y Specify the lower left corner of the scissor box.  Initially (0, 0).
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  22.      _w_i_d_t_h, _h_e_i_g_h_t
  23.           Specify the width and height of the scissor box.  When a GL context
  24.           is first attached to a window, _w_i_d_t_h and _h_e_i_g_h_t are set to the
  25.           dimensions of that window.
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  27. DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
  28.      ggggllllSSSScccciiiissssssssoooorrrr defines a rectangle, called the scissor box, in window
  29.      coordinates.  The first two arguments, _x and _y, specify the lower left
  30.      corner of the box.  _w_i_d_t_h and _h_e_i_g_h_t specify the width and height of the
  31.      box.
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  33.      To enable and disable the scissor test, call ggggllllEEEEnnnnaaaabbbblllleeee and ggggllllDDDDiiiissssaaaabbbblllleeee with
  34.      argument GGGGLLLL____SSSSCCCCIIIISSSSSSSSOOOORRRR____TTTTEEEESSSSTTTT. The test is initially disabled. While the test
  35.      is enabled, only pixels that lie within the scissor box can be modified
  36.      by drawing commands.  Window coordinates have integer values at the
  37.      shared corners of frame buffer pixels.  glScissor(0,0,1,1) aaaalllllllloooowwwwssss
  38.      mmmmooooddddiiiiffffiiiiccccaaaattttiiiioooonnnn ooooffff oooonnnnllllyyyy tttthhhheeee lllloooowwwweeeerrrr lllleeeefffftttt ppppiiiixxxxeeeellll iiiinnnn tttthhhheeee wwwwiiiinnnnddddoooowwww,,,, aaaannnndddd
  39.      ggggllllSSSScccciiiissssssssoooorrrr((((0000,,,,0000,,,,0000,,,,0000)))) doesn't allow modification of any pixels in the
  40.      window.
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  42.      When the scissor test is disabled, it is as though the scissor box
  43.      includes the entire window.
  44.  
  45. EEEERRRRRRRROOOORRRRSSSS
  46.      GGGGLLLL____IIIINNNNVVVVAAAALLLLIIIIDDDD____VVVVAAAALLLLUUUUEEEE is generated if either _w_i_d_t_h or _h_e_i_g_h_t is negative.
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  48.      GGGGLLLL____IIIINNNNVVVVAAAALLLLIIIIDDDD____OOOOPPPPEEEERRRRAAAATTTTIIIIOOOONNNN is generated if ggggllllSSSScccciiiissssssssoooorrrr is executed between the
  49.      execution of ggggllllBBBBeeeeggggiiiinnnn and the corresponding execution of ggggllllEEEEnnnndddd.
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  63.                                                                         PPPPaaaaggggeeee 1111
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  70. ggggllllSSSScccciiiissssssssoooorrrr((((3333GGGG))))                  OOOOppppeeeennnnGGGGLLLL RRRReeeeffffeeeerrrreeeennnncccceeee                  ggggllllSSSScccciiiissssssssoooorrrr((((3333GGGG))))
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  74. AAAASSSSSSSSOOOOCCCCIIIIAAAATTTTEEEEDDDD GGGGEEEETTTTSSSS
  75.      ggggllllGGGGeeeetttt with argument GGGGLLLL____SSSSCCCCIIIISSSSSSSSOOOORRRR____BBBBOOOOXXXX
  76.      ggggllllIIIIssssEEEEnnnnaaaabbbblllleeeedddd with argument GGGGLLLL____SSSSCCCCIIIISSSSSSSSOOOORRRR____TTTTEEEESSSSTTTT
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  79. SSSSEEEEEEEE AAAALLLLSSSSOOOO
  80.      ggggllllEEEEnnnnaaaabbbblllleeee, ggggllllVVVViiiieeeewwwwppppoooorrrrtttt
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  129.                                                                         PPPPaaaaggggeeee 2222
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