v.drape(1)

1v.drape(1)                    Grass User's Manual                   v.drape(1)
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NAME

6       v.drape   -  Converts  2D  vector to 3D vector by sampling of elevation
7       raster. Default sampling by nearest neighbor.
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KEYWORDS

10       vector
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SYNOPSIS

13       v.drape
14       v.drape help
15       v.drape    input=name     [type=string[,string,...]]      [rast=string]
16       [method=string]  output=name  [--overwrite]  [--verbose]  [--quiet]
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18   Flags:
19       --overwrite
20           Allow output files to overwrite existing files
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22       --verbose
23           Verbose module output
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25       --quiet
26           Quiet module output
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28   Parameters:
29       input=name
30           Name of input vector map
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32       type=string[,string,...]
33           Type
34           Feature type(s)
35           Options: point,centroid,line,boundary,face,kernel
36           Default: point,centroid,line,boundary,face,kernel
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38       rast=string
39           Elevation raster for height extraction
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41       method=string
42           Sampling method
43           Options: nearest,bilinear,cubic
44           Default: nearest
45           nearest: nearest neighbor
46           bilinear: bilinear interpolation
47           cubic: cubic convolution interpolation
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49       output=name
50           Name for output vector map
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DESCRIPTION

53       v.drape converts 2D vector point or line data into 3D vector format via
54       sampling of an elevation surface.  Three  sampling  algorithms  adapted
55       fromv  v.sample  were  incorporated into this module: nearest neighbor,
56       bilinear, and cubic convultion.
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NOTES

59       Please run beforehand
60       g.region vect=2D_vector
61        and make sure that the extent of the elevation raster is at  least  as
62       big as the vector to convert.
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64       Additional vertices can be added to the input 2D vector with v.split.
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66       The  module  can be used in conjunction with v.out.pov and r.out.pov to
67       export a complete set of vector and raster data for display in POVRAY.
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EXAMPLE

70       Spearfish example:
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73       g.region -p vect=roads align=elevation.10m
74       v.drape in=roads rast=elevation.10m method=bilinear out=roads3d
75       v.info roads3d
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POVRAY EXAMPLE

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80       #setup the region
81       g.region vect=roads align=elevation.10m -p
82       #export the vector data
83       v.drape in=roads out=roads3d rast=elevation.10m
84       v.out.pov roads3d out=roads3d.pov
85       #export the raster data
86       r.out.pov elevation.10m tga=elevation.tga
87       r.out.png landcover.30m out=landcover30m.png
88       # now write a complete povray-script and launch povray
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ERROR MESSAGES

92       If the following error message appears
93        WARNING: [demname in mapset] - read request  for  row  -1  is  outside
94       region
95        ERROR: problem reading raster cell file
96         it  indicates that the vector map is spatially larger than the raster
97       map.  To avoid this problem, the vector map needs to be clipped to  the
98       raster map extent, for example:
99       g.region rast=demname
100       v.in.region clipbox
101       v.overlay ain=clipbox bin=vectmap out=vectmap_clipped op=and
102       v.drape vectmap_clipped out=vectdrape rast=demname
103        Then v.drape should perform the draping.
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AUTHOR

109       Dylan Beaudette, University of California at Davis.
110       Raster sampling routines borrowed from v.sample.
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112       Last changed: $Date: 2007-07-09 17:15:36 +0200 (Mon, 09 Jul 2007) $
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114       Full index
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116       © 2003-2008 GRASS Development Team
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120GRASS 6.3.0                                                         v.drape(1)