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
16       [--verbose]  [--quiet]
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18   Parameters:
19       elev=string
20           Name of elevation map
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22       color=string
23           Name of color file
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25       exag=float
26           Vertical exaggeration
27           Default: 1.0
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29       output=string
30           Name for new VRML file
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DESCRIPTION

33       This  module exports a GRASS raster map to the Virtual Reality Modeling
34       Language (VRML) format for 3D visualization.
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36       This version only outputs raster maps in VRML 1.0  format.   The  newer
37       VRML  2.0 format will be more efficient for geographic applications, as
38       it introduces an "ElevationGrid" node so that only the elevation points
39       will have to be written instead of the whole geometry.  The vast major‐
40       ity of VRML viewers currently only support VRML 1.0.  If the  extension
41       "wrl"  (world)  is  not  present in the he output parameter, it will be
42       added.
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WARNING

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

54       This is a preliminary release of "r.out.vrml".  For further information
55       about VRML and available viewers for various platforms, see:
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57       VRML Virtual Reality Modeling Language
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BUGS:

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

67       Update  to  the more modern GeoVRML format, or probably better the next
68       generation X3D format.  See also the Xj3D project.
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70       Future plans for this module are to allow draping of sites objects  and
71       vector  maps and using the new sites format available in floating point
72       GRASS to embed WWW links into site objects. It will also be upgraded to
73       support  VRML 2.0 and will allow entering multiple preset "views" using
74       the existing GRASS 3d_view file format.
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76       Other possible additions:
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78                      Allow animation of elevation, color, or sites  based  on
79                     user interaction.
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81                      Degradation  of  the raster to produce TINs for improved
82                     performance.
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AUTHOR

85       Bill Brown, US Army Construction Engineering Research Laboratory
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87       Last changed: $Date: 2006-12-13 17:10:28 +0100 (Wed, 13 Dec 2006) $
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89       Full index
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91       © 2003-2008 GRASS Development Team
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95GRASS 6.3.0                                                      r.out.vrml(1)