1r.out.vrml(1)                 Grass User's Manual                r.out.vrml(1)
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NAME

6       r.out.vrml   - Export a raster map to the Virtual Reality Modeling Lan‐
7       guage (VRML)
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KEYWORDS

10       raster, export, VRML
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SYNOPSIS

13       r.out.vrml
14       r.out.vrml help
15       r.out.vrml elev=string  [color=string]   [exag=float]  output=string
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17   Parameters:
18       elev=string
19           Name of elevation map
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21       color=string
22           Name of color file
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24       exag=float
25           Vertical exaggeration Default: 1.0
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27       output=string
28           Name for new VRML file
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DESCRIPTION

31       This version only outputs raster maps in VRML 1.0  format.   The  newer
32       VRML  2.0 format will be more efficient for geographic applications, as
33       it introduces an "ElevationGrid" node so that only the elevation points
34       will have to be written instead of the whole geometry.  The vast major‐
35       ity of VRML viewers currently only support VRML 1.0.  If the  extension
36       "wrl"  (world)  is  not  present in the he output parameter, it will be
37       added.
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WARNING:

40       VRML is not well suited for large geometrys which can result from  even
41       a  small  geographic  region.   Most viewers seem to bog down with more
42       than 12,000 polygons, depending on your  hardware  &  specific  viewer.
43       Each  grid  cell  results  in two polygons, so a reasonable size region
44       would be something less than about 75x75.  For improved performance and
45       smaller  file  size,  leave off a color map.  Since VRML is ascii text,
46       gzip works very well to significantly compress file size.
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BUGS:

49       Currently the region is transformed to a unit size, so real  geographic
50       location  is lost.  Side effects when working in a lat-lon location are
51       that besides general distortion due to projection, a very  small  exag‐
52       geration  factor (on order of .001) must be used to compensate for ver‐
53       tical units expected to be the same as map units.
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NOTE

56       This is a preliminary release of "p.out.vrml".  For further information
57       about VRML and available viewers for various platforms, see:
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59       VRML Virtual Reality Modeling Language
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TODO

62       Future  plans for this module are to allow draping of sites objects and
63       vector files and using the new sites format available in floating point
64       GRASS to embed WWW links into site objects. It will also be upgraded to
65       support VRML 2.0 and will allow entering multiple preset "views"  using
66       the existing GRASS 3d_view file format.
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68       Other possible additions:
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70                      Allow  animation  of elevation, color, or sites based on
71                     user interaction.
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73                      Degradation of the raster to produce TINs  for  improved
74                     performance.
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AUTHOR

77       Bill Brown, US Army Construction Engineering Research Laboratory
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79       Last changed: $Date: 2006/10/29 15:03:54 $
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81       Full index
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85GRASS 6.2.2                                                      r.out.vrml(1)