1SRFACE(3NCARG)                   NCAR GRAPHICS                  SRFACE(3NCARG)
2
3
4

NAME

6       SRFACE - Draws a perspective picture of a function of two variables
7       with hidden lines removed. The function is approximated by a two-
8       dimensional array of heights.
9

SYNOPSIS

11       CALL SRFACE (X,Y,Z,M,MX,NX,NY,S,STEREO)
12

C-BINDING SYNOPSIS

14       #include <ncarg/ncargC.h>
15
16       void c_srface (float *x, float *y, float *z, int *m,
17       int mx, int nx, int ny, float s[6], float stereo)
18

DESCRIPTION

20       X           A linear array NX long containing the X coordinates of the
21                   points in the surface approximation.  See "USAGE" below.
22
23       Y           The linear array NY long containing the Y coordinates of
24                   the points in the surface approximation.  See "USAGE"
25                   below.
26
27       Z           An array MX by NY containing the surface to be drawn in NX
28                   by NY cells. Z(I,J) = F(X(I),Y(J)).  See "USAGE" below.
29
30       M           Scratch array at least 2*NX*NY words long.
31
32       MX          First dimension of Z.
33
34       NX          Number of data values in the X direction (the first
35                   subscript direction) in Z to be plotted.  When plotting an
36                   entire array, MX=NX.
37
38       NY          Number of data values in the Y direction (the second
39                   subscript direction) to be plotted.
40
41       S           S defines the line of sight. The viewer's eye is at (S(1),
42                   S(2), S(3)) and the point looked at is at (S(4), S(5),
43                   S(6)). The eye should be outside the block with opposite
44                   corners (X(1), Y(1), ZMIN) and (X(NX), Y(NY), ZMAX) and the
45                   point looked at should be inside it. For a nice perspective
46                   effect, the distance between the eye and the point looked
47                   at should be 5 to 10 times the size of the block.
48
49       STEREO      Flag to indicate if stereo pairs are to be drawn.  0.0
50                   means no stereo pair (one picture). Non-zero means put out
51                   two pictures. The value of STEREO is the relative angle
52                   between the eyes. A value of 1.0 produces standard
53                   separation. Negative STEREO reverses the left and right
54                   figures.
55

C-BINDING DESCRIPTION

57       The C-binding argument descriptions are the same as the FORTRAN
58       argument descriptions, with the following exceptions:
59
60
61       z           An array ny by mx.
62
63       mx          Second dimension of z.
64
65       nx          Number of data values in the y direction (the second
66                   subscript direction) in z to be plotted.  When plotting an
67                   entire array, mx=nx.
68
69       ny          Number of data values in the x direction (the first
70                   subscript direction) to be plotted.
71

USAGE

73       · The range of Z compared with the range of X and Y determines the
74         shape of the picture. They are assumed to be in the same units and
75         not wildly different in magnitude. S is assumed to be in the same
76         units as X, Y, and Z.
77
78
79       · Picture size can be made relative to distance.
80
81
82       · TRN32S can be used to translate from 3 space to 2 space.
83
84
85       · Data with extreme discontinuities may cause visibility errors. If
86         this problem occurs, use a distant eye position away from the +Z
87         axis.
88
89
90       · The default line color is set to color index 1. If the user wishes to
91         change the line color, he can do so by defining color index 1 before
92         calling SRFACE, or by putting the common block SRFINT in his calling
93         program and defining and using color index ISRFMJ (defaulted to 1 in
94         BLOCKDATA).
95

EXAMPLES

97       Use the ncargex command to see the following relevant examples: srex01,
98       tpwrzs, tsrfac, fsrpwrzs, fsrsrfac.
99

ACCESS

101       To use SRFACE or c_srface, load the NCAR Graphics libraries ncarg,
102       ncarg_gks, and ncarg_c, preferably in that order.
103

SEE ALSO

105       Online: surface, surface_params, ezsrfc, pwrzs, setr, ncarg_cbind.
106
107       Hardcopy: NCAR Graphics Fundamentals, UNIX Version
108

110       Copyright (C) 1987-2007
111       University Corporation for Atmospheric Research
112
113       This documentation is free software; you can redistribute it and/or
114       modify it under the terms of the GNU General Public License as
115       published by the Free Software Foundation; either version 2 of the
116       License, or (at your option) any later version.
117
118       This software is distributed in the hope that it will be useful, but
119       WITHOUT ANY WARRANTY; without even the implied warranty of
120       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
121       General Public License for more details.
122
123       You should have received a copy of the GNU General Public License along
124       with this software; if not, write to the Free Software Foundation,
125       Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
126
127
128
129UNIX                              March 1993                    SRFACE(3NCARG)
Impressum