1TDCTRI(3NCARG) NCAR GRAPHICS TDCTRI(3NCARG)
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6 TDCTRI - Cut triangles defined by a triangle list.
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9 CALL TDCTRI (RTRI, MTRI, NTRI, IAXS, RCUT)
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12 #include <ncarg/ncargC.h>
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14 void c_tdctri(float *rtri, int mtri, int *ntri, int iaxs, float rcut)
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17 This routine, given a list of NTRI triangles in the array RTRI, an axis
18 identifier IAXS (1 => U axis, 2 => V axis, 3 => W axis), and a value
19 RCUT along that axis, cuts all the triangles that intersect the plane
20 perpendicular to the identified axis at the specified value into two
21 pieces, one on either side of the plane. This is useful when one is
22 rendering the triangles in colors that depend on their position in U,
23 V, or W. (See the example "tdex04".)
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25 The arguments of TDCTRI are as follows:
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27 RTRI (an input/output array, of type REAL, dimensioned 10 x MTRI) -
28 a list of triangles, probably created by means of calls to
29 TDSTRI, TDITRI, and/or TDMTRI. The number of triangles in the
30 list may increase as a result of calling TDCTRI.
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32 MTRI (an input expression of type INTEGER) - the second dimension of
33 RTRI and thus the maximum number of triangles the triangle list
34 will hold.
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36 NTRI (an input/output variable of type INTEGER) - specifies the
37 number of triangles currently in the list. It is the user's
38 responsibility to zero this initially; its value is increased
39 by each call to a triangle-generating routine like TDSTRI or
40 TDITRI and may be increased by a call to TDCTRI.
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42 IAXS (an input variable of type INTEGER) - specifies the axis to
43 which the cut plane is perpendicular (1 => U axis, 2 => V axis,
44 3 => W axis).
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46 RCUT (an input variable of type REAL) - specifies that value of U,
47 V, or W at which the cut plane intersects the axis.
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50 The C-binding argument descriptions are the same as the FORTRAN
51 argument descriptions.
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54 To use TDCTRI or c_tdctri, load the NCAR Graphics libraries ncarg,
55 ncarg_gks, and ncarg_c, preferably in that order.
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58 Online: tdclrs, tddtri, tdgeti, tdgetr, tdgrds, tdgrid, tdgtrs, tdinit,
59 tditri, tdlbla, tdlbls, tdline, tdlnpa, tdmtri, tdpack, tdpack_params,
60 tdpara, tdplch, tdprpa, tdprpi, tdprpt, tdseti, tdsetr, tdsort, tdstri,
61 tdstrs
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64 Copyright (C) 1987-2007
65 University Corporation for Atmospheric Research
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67 This documentation is free software; you can redistribute it and/or
68 modify it under the terms of the GNU General Public License as
69 published by the Free Software Foundation; either version 2 of the
70 License, or (at your option) any later version.
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72 This software is distributed in the hope that it will be useful, but
73 WITHOUT ANY WARRANTY; without even the implied warranty of
74 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
75 General Public License for more details.
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77 You should have received a copy of the GNU General Public License along
78 with this software; if not, write to the Free Software Foundation,
79 Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
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84UNIX July 1997 TDCTRI(3NCARG)