1STUMSL(3NCARG) NCAR GRAPHICS STUMSL(3NCARG)
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6 STUMSL - This routine is the user-definable external subroutine used to
7 draw masked streamlines. The default version of the routine draws any
8 polyline all of whose area identifiers are greater than or equal to
9 zero.
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12 CALL STUMSL (XCS,YCS,NCS,IAI,IAG,NAI)
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15 XCS (REAL array, assumed size NCS, input): Array of X
16 coordinates of the points defining the polyline with the
17 given set of area identifiers.
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19 YCS (REAL array, assumed size NCS, input): Array of Y
20 coordinates of the points defining the polyline with the
21 given set of area identifiers.
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23 NCS (INTEGER, input): Number of points; assumed size of the X
24 and Y coordinate arrays, XCS and YCS.
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26 IAI (INTEGER array, assumed size NAI, input): Array of area
27 identifier values. Each value represents the area
28 identifier with respect to the area group in the area group
29 array with the same array index.
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31 IAG (INTEGER array, assumed size NAI, input): Array of area-
32 identifier groups.
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34 NAI (INTEGER, input): Number of area identifier groups. The
35 current version of Streamlines supports up to 64 area
36 groups.
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39 ´STUMSL´ is the name given to the default version of the masked
40 streamline drawing routine, and it is also the name given to the
41 argument through which the external subroutine is passed to STREAM.
42 However, you may choose any acceptable FORTRAN identifier as the name
43 of a user-defined version of the routine. The substitute routine must
44 have an argument list equivalent to the default version of STUMSL.
45 Also, whether or not the default version is used, the subroutine that
46 calls STREAM should contain an external declaration of the routine,
47 such as:
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49 EXTERNAL STUMSL
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51 If the MSK parameter is greater than 0, signifying that masking is to
52 be performed, Streamlines sends one or more sets of X and Y polyline
53 coordinate arrays to the area masking routine, ARDRLN, for each
54 streamline. ARDRLN subdivides the polyline into pieces such that each
55 smaller polyline has a single area identifier with respect to each area
56 identifier group, then makes a call to STUMSL for each polyline piece.
57 While the default version of STUMSL only checks to see that none of the
58 area identifiers are negative, a user-defined version could perform
59 more complicated decision processing based on knowledge of the meaning
60 of specific area identifier groups and/or area identifier values. Note
61 that, before invoking STUMSL, ARDRLN modifies the user coordinate space
62 by making the following calls:
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64 CALL GETSET(VPL,VPR,VPB,VPT,WDL,WDR,WDB,WDT,LLG) CALL
65 SET(VPL,VPR,VPB,VPT,VPL,VPR,VPB,VPT,1)
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67 These calls temporarily turn the user to NDC mapping into an identity,
68 allowing the user to call any of the routines, CURVE, CURVED, or the
69 GKS routine GPL, to render the polygon piece without worrying about a
70 possible non-identity mapping between user and world coordinates.
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72 The current version of Streamlines supports masked drawing with up to
73 64 area groups. Streamlines will exit with an error message if an area
74 map with more than 64 groups is passed to it.
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77 To use STUMSL, load the NCAR Graphics libraries ncarg, ncarg_gks, and
78 ncarg_c, preferably in that order.
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81 Online: stgetc, stgeti, stgetr, stinit, stream, streamlines,
82 streamlines_params, strset, stsetc, stseti, stsetr, stuixy, stumta,
83 stumxy, ncarg_cbind.
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85 Hardcopy: NCAR Graphics Fundamentals, UNIX Version
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88 Copyright (C) 1987-2009
89 University Corporation for Atmospheric Research
90 The use of this Software is governed by a License Agreement.
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94UNIX April 1993 STUMSL(3NCARG)