1PLW3D(3plplot)                    PLplot API                    PLW3D(3plplot)
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NAME

6       plw3d - Configure the transformations required for projecting a 3D sur‐
7       face on a 2D window
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SYNOPSIS

10       plw3d(basex, basey, height, xmin, xmax, ymin, ymax,  zmin,  zmax,  alt,
11       az)
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DESCRIPTION

14       Configure  the  transformations required for projecting a 3D surface on
15       an existing 2D window.  Those transformations (see the PLplot  documen‐
16       tation) are done to a rectangular cuboid enclosing the 3D surface which
17       has its limits expressed in 3D world coordinates and also normalized 3D
18       coordinates  (used  for  interpreting  the  altitude and azimuth of the
19       viewing angle).  The transformations consist of  the  linear  transform
20       from  3D world coordinates to normalized 3D coordinates, and the 3D ro‐
21       tation of normalized coordinates required to align the pole of the  new
22       3D  coordinate  system with the viewing direction specified by altitude
23       and azimuth so that x and y of the surface elements in that transformed
24       coordinate system are the projection of the 3D surface with given view‐
25       ing direction on the 2D window.
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27       The enclosing rectangular cuboid for the surface  plot  is  defined  by
28       xmin,  xmax,  ymin, ymax, zmin and zmax in 3D world coordinates.  It is
29       mapped into the same rectangular cuboid with normalized  3D  coordinate
30       sizes  of  basex by basey by height so that xmin maps to -basex/2, xmax
31       maps to basex/2, ymin maps to -basey/2, ymax maps to basey/2, zmin maps
32       to 0 and zmax maps to height.  The resulting rectangular cuboid in nor‐
33       malized coordinates is then viewed by an observer at altitude  alt  and
34       azimuth  az.  This routine must be called before plbox3(3plplot) or any
35       of the 3D surface plotting routines; plmesh(3plplot), plmeshc(3plplot),
36       plot3d(3plplot),          plot3dc(3plplot),          plot3dcl(3plplot),
37       plsurf3d(3plplot), plsurf3dl(3plplot) or plfill3(3plplot).
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39       Redacted form: plw3d(basex, basey,  height,  xmin,  xmax,  ymin,  ymax,
40       zmin, zmax, alt, az)
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42       This function is examples 8, 11, 18, and 21.
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ARGUMENTS

45       basex (PLFLT(3plplot), input)
46              The normalized x coordinate size of the rectangular cuboid.
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48       basey (PLFLT(3plplot), input)
49              The normalized y coordinate size of the rectangular cuboid.
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51       height (PLFLT(3plplot), input)
52              The normalized z coordinate size of the rectangular cuboid.
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54       xmin (PLFLT(3plplot), input)
55              The minimum x world coordinate of the rectangular cuboid.
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57       xmax (PLFLT(3plplot), input)
58              The maximum x world coordinate of the rectangular cuboid.
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60       ymin (PLFLT(3plplot), input)
61              The minimum y world coordinate of the rectangular cuboid.
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63       ymax (PLFLT(3plplot), input)
64              The maximum y world coordinate of the rectangular cuboid.
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66       zmin (PLFLT(3plplot), input)
67              The minimum z world coordinate of the rectangular cuboid.
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69       zmax (PLFLT(3plplot), input)
70              The maximum z world coordinate of the rectangular cuboid.
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72       alt (PLFLT(3plplot), input)
73              The  viewing  altitude in degrees above the xy plane of the rec‐
74              tangular cuboid in normalized coordinates.
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76       az (PLFLT(3plplot), input)
77              The viewing azimuth in degrees of the rectangular cuboid in nor‐
78              malized  coordinates.   When  az=0, the observer is looking face
79              onto the zx plane of the rectangular cuboid in normalized  coor‐
80              dinates,  and  as  az is increased, the observer moves clockwise
81              around that cuboid when viewed from above the xy plane.
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AUTHORS

85       Many developers (who  are  credited  at  http://plplot.org/credits.php)
86       have contributed to PLplot over its long history.
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SEE ALSO

89       PLplot documentation at http://plplot.org/documentation.php.
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93                                 August, 2021                   PLW3D(3plplot)
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