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/ IRIX Base Documentation 2002 November / SGI IRIX Base Documentation 2002 November.iso / usr / share / catman / g_man / cat3 / OpenGL-ftn / fglmapgrid.z / fglmapgrid
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Text File  |  2002-10-03  |  7.4 KB  |  133 lines
  1.  
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  4. ffffggggllllMMMMaaaappppGGGGrrrriiiidddd((((3333GGGG))))                 OOOOppppeeeennnnGGGGLLLL RRRReeeeffffeeeerrrreeeennnncccceeee                 ffffggggllllMMMMaaaappppGGGGrrrriiiidddd((((3333GGGG))))
  5.  
  6.  
  7.  
  8. NNNNAAAAMMMMEEEE
  9.      ffffggggllllMMMMaaaappppGGGGrrrriiiidddd1111dddd,,,, ffffggggllllMMMMaaaappppGGGGrrrriiiidddd1111ffff,,,, ffffggggllllMMMMaaaappppGGGGrrrriiiidddd2222dddd,,,, ffffggggllllMMMMaaaappppGGGGrrrriiiidddd2222ffff - define a one- or
  10.      two-dimensional mesh
  11.  
  12.  
  13. FFFFOOOORRRRTTTTRRRRAAAANNNN SSSSPPPPEEEECCCCIIIIFFFFIIIICCCCAAAATTTTIIIIOOOONNNN
  14.      SUBROUTINE ffffggggllllMMMMaaaappppGGGGrrrriiiidddd1111dddd( INTEGER*4 _u_n,
  15.                               REAL*4 _u_1,
  16.                               REAL*4 _u_2 )
  17.      SUBROUTINE ffffggggllllMMMMaaaappppGGGGrrrriiiidddd1111ffff( INTEGER*4 _u_n,
  18.                               REAL*4 _u_1,
  19.                               REAL*4 _u_2 )
  20.      SUBROUTINE ffffggggllllMMMMaaaappppGGGGrrrriiiidddd2222dddd( INTEGER*4 _u_n,
  21.                               REAL*4 _u_1,
  22.                               REAL*4 _u_2,
  23.                               INTEGER*4 _v_n,
  24.                               REAL*4 _v_1,
  25.                               REAL*4 _v_2 )
  26.      SUBROUTINE ffffggggllllMMMMaaaappppGGGGrrrriiiidddd2222ffff( INTEGER*4 _u_n,
  27.                               REAL*4 _u_1,
  28.                               REAL*4 _u_2,
  29.                               INTEGER*4 _v_n,
  30.                               REAL*4 _v_1,
  31.                               REAL*4 _v_2 )
  32.  
  33.  
  34. PPPPAAAARRRRAAAAMMMMEEEETTTTEEEERRRRSSSS
  35.      _u_n  Specifies the number of partitions in the grid range interval [_u_1,
  36.          _u_2].  Must be positive.
  37.  
  38.      _u_1, _u_2
  39.          Specify the mappings for integer grid domain values i = 0 and i = un.
  40.  
  41.      _v_n  Specifies the number of partitions in the grid range interval [_v_1,
  42.          _v_2] (ffffggggllllMMMMaaaappppGGGGrrrriiiidddd2222 only).
  43.  
  44.      _v_1, _v_2
  45.          Specify the mappings for integer grid domain values j = 0 and j = vn
  46.          (ffffggggllllMMMMaaaappppGGGGrrrriiiidddd2222 only).
  47.  
  48. DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
  49.      ffffggggllllMMMMaaaappppGGGGrrrriiiidddd and ffffggggllllEEEEvvvvaaaallllMMMMeeeesssshhhh are used together to efficiently generate and
  50.      evaluate a series of evenly-spaced map domain values.  ffffggggllllEEEEvvvvaaaallllMMMMeeeesssshhhh steps
  51.      through the integer domain of a one- or two-dimensional grid, whose range
  52.      is the domain of the evaluation maps specified by ffffggggllllMMMMaaaapppp1111 and ffffggggllllMMMMaaaapppp2222.
  53.  
  54.      ffffggggllllMMMMaaaappppGGGGrrrriiiidddd1111 and ffffggggllllMMMMaaaappppGGGGrrrriiiidddd2222 specify the linear grid mappings between the
  55.      i (or i and j) integer grid coordinates, to the u (or u and v) floating-
  56.      point evaluation map coordinates.  See ffffggggllllMMMMaaaapppp1111 and ffffggggllllMMMMaaaapppp2222 for details of
  57.      how u and v coordinates are evaluated.
  58.  
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  60.  
  61.  
  62.  
  63.                                                                         PPPPaaaaggggeeee 1111
  64.  
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  69.  
  70. ffffggggllllMMMMaaaappppGGGGrrrriiiidddd((((3333GGGG))))                 OOOOppppeeeennnnGGGGLLLL RRRReeeeffffeeeerrrreeeennnncccceeee                 ffffggggllllMMMMaaaappppGGGGrrrriiiidddd((((3333GGGG))))
  71.  
  72.  
  73.  
  74.      ffffggggllllMMMMaaaappppGGGGrrrriiiidddd1111 specifies a single linear mapping such that integer grid
  75.      coordinate 0 maps exactly to _u_1, and integer grid coordinate _u_n maps
  76.      exactly to _u_2.  All other integer grid coordinates i are mapped so that
  77.  
  78.                                u = i(u2-u1)/un + u1
  79.  
  80.      ffffggggllllMMMMaaaappppGGGGrrrriiiidddd2222 specifies two such linear mappings.  One maps integer grid
  81.      coordinate i = 0 exactly to _u_1, and integer grid coordinate i = un
  82.      exactly to _u_2.  The other maps integer grid coordinate j = 0 exactly to
  83.      _v_1, and integer grid coordinate j = vn exactly to _v_2.  Other integer grid
  84.      coordinates i and j are mapped such that
  85.  
  86.                                u = i(u2-u1)/un + u1
  87.  
  88.                                v = j(v2-v1)/vn + v1
  89.  
  90.      The mappings specified by ffffggggllllMMMMaaaappppGGGGrrrriiiidddd are used identically by ffffggggllllEEEEvvvvaaaallllMMMMeeeesssshhhh
  91.      and ffffggggllllEEEEvvvvaaaallllPPPPooooiiiinnnntttt.
  92.  
  93. EEEERRRRRRRROOOORRRRSSSS
  94.      GGGGLLLL____IIIINNNNVVVVAAAALLLLIIIIDDDD____VVVVAAAALLLLUUUUEEEE is generated if either _u_n or _v_n is not positive.
  95.  
  96.      GGGGLLLL____IIIINNNNVVVVAAAALLLLIIIIDDDD____OOOOPPPPEEEERRRRAAAATTTTIIIIOOOONNNN is generated if ffffggggllllMMMMaaaappppGGGGrrrriiiidddd is executed between the
  97.      execution of ffffggggllllBBBBeeeeggggiiiinnnn and the corresponding execution of ffffggggllllEEEEnnnndddd.
  98.  
  99. AAAASSSSSSSSOOOOCCCCIIIIAAAATTTTEEEEDDDD GGGGEEEETTTTSSSS
  100.      ffffggggllllGGGGeeeetttt with argument GGGGLLLL____MMMMAAAAPPPP1111____GGGGRRRRIIIIDDDD____DDDDOOOOMMMMAAAAIIIINNNN
  101.      ffffggggllllGGGGeeeetttt with argument GGGGLLLL____MMMMAAAAPPPP2222____GGGGRRRRIIIIDDDD____DDDDOOOOMMMMAAAAIIIINNNN
  102.      ffffggggllllGGGGeeeetttt with argument GGGGLLLL____MMMMAAAAPPPP1111____GGGGRRRRIIIIDDDD____SSSSEEEEGGGGMMMMEEEENNNNTTTTSSSS
  103.      ffffggggllllGGGGeeeetttt with argument GGGGLLLL____MMMMAAAAPPPP2222____GGGGRRRRIIIIDDDD____SSSSEEEEGGGGMMMMEEEENNNNTTTTSSSS
  104.  
  105.  
  106. SSSSEEEEEEEE AAAALLLLSSSSOOOO
  107.      ffffggggllllEEEEvvvvaaaallllCCCCoooooooorrrrdddd, ffffggggllllEEEEvvvvaaaallllMMMMeeeesssshhhh, ffffggggllllEEEEvvvvaaaallllPPPPooooiiiinnnntttt, ffffggggllllMMMMaaaapppp1111, ffffggggllllMMMMaaaapppp2222
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  129.                                                                         PPPPaaaaggggeeee 2222
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  133.