v.drape(1)

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

6       v.drape   -  Convert  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]
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18   Flags:
19       --overwrite
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21   Parameters:
22       input=name
23           Name of input vector map
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25       type=string[,string,...]
26           Type   Options:  point,centroid,line,boundary,face,kernel  Default:
27           point,centroid,line,boundary,face,kernel
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29       rast=string
30           Elevation raster for height extraction
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32       method=string
33           Sampling method Options:  nearest,bilinear,cubic  Default:  nearest
34           nearest:  nearest  neighbor bilinear: bilinear interpolation cubic:
35           cubic convolution interpolation
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37       output=name
38           Name for output vector map
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DESCRIPTION

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

47       Please run beforehand
48       g.region vect=2D_vector
49         and  make sure that the extent of the elevation raster is at least as
50       big as the vector to convert.
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52       Additional vertices can be added to the input 2D vector with v.split.
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54       The module can be used in conjunction with v.out.pov and  r.out.pov  to
55       export a complete set of vector and raster data for display in POVRAY.
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EXAMPLE

58       Spearfish example:
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61       g.region -p vect=roads align=elevation.10m
62       v.drape in=roads rast=elevation.10m method=bilinear out=roads3d
63       v.info roads3d
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POVRAY EXAMPLE

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68       #setup the region
69       g.region vect=roads align=elevation.10m -p
70       #export the vector data
71       v.drape in=roads out=roads3d rast=elevation.10m
72       v.out.pov roads3d out=roads3d.pov
73       #export the raster data
74       r.out.pov elevation.10m tga=elevation.tga
75       r.out.png landcover.30m out=landcover30m.png
76       # now write a complete povray-script and launch povray
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ERROR MESSAGES

80       If the following error message appears
81        WARNING:  [demname  in  mapset]  -  read request for row -1 is outside
82       region
83        ERROR: problem reading raster cell file
84        it indicates that the vector map is spatially larger than  the  raster
85       map.   To avoid this problem, the vector map needs to be clipped to the
86       raster map extent, for example:
87       g.region rast=demname
88       v.in.region clipbox
89       v.overlay ain=clipbox bin=vectmap out=vectmap_clipped op=and
90       v.drape vectmap_clipped out=vectdrape rast=demname
91        Then v.drape should perform the draping.
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AUTHOR

97       Dylan Beaudette, University of California at Davis.
98       Raster sampling routines borrowed from v.sample.
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100       Last changed: $Date: 2007/07/09 15:15:57 $
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102       Full index
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106GRASS 6.2.2                                                         v.drape(1)