mbgrd2obj
Section:  MB-System 5.0  (1)
Updated:  22 September 2020 
Index


 
NAME

mbgrd2obj - GMT plug-in module to convert grid to OBJ format 3D model file.

 
VERSION

Version 5.0

 
SYNOPSIS

mbgrd2obj <gridfile> -G<objfile> [-R<west>/<east>/<south>/<north>[+r]] [-V[<level>]]

 
DESCRIPTION

mbgrd2obj is a plug-in module to generate a Geographically located
GeoTiff image from a GMT grid file using GMT (Generic Mapping Tools).
Like mbgrdtiff, mbcontour, and mbswath, mbgrd2obj
is fully compatible with the GMT package version 6.

The OBJ format is used for 3D model files that can be imported into visualization
software or used by 3D printers. This open format was developed by Wavefront Technologies
for it's visualization animation software, and has since been widely adopted in
the 3D graphics and printing industries. This is a text based format that
defines the geometry of objects and surfaces, and can also define color and texture.
The OBJ files generated by mbgrd2obj represent the topographic surface
derived from the input grid file as a set of triangles without color or texture
information (though those capabilities may be added later). The -R option
caan be used to specify the bounds of the OBJ output; these bounds must be a
subset of the area covered by the input grid. Areas of the grid represented as
having no data are not included in the OBJ output. By default, the output OBJ
file is named by replacing the ".grd" suffix of the input grid file with ".obj",
or adding the ".obj" suffix to the input filename if the input does not have a
".grd" suffix. The -G option can be used to specify a different output
OBJ file name.

In order for GMT to successfully execute mbgrd2obj, the
location of the shared library libmbgmt containing this module must be known to GMT.
This can be accomplished by either setting the GMT_CUSTOM_LIBS parameter
in the file gmt.conf that is part of the GMT installation, by setting
this parameter in the file gmt.conf in the user's home directory, or by
using the GMT module gmtset to modify this parameter in the
current working directory. If, for instance, the libmbgmt shared library
has been installed in the file /usr/lib/libmbgmt.dylib, then the
GMT_CUSTOM_LIBS parameter in a gmt.conf file can be set to:

        GMT_CUSTOM_LIBS = /usr/lib/libmbgmt.dylib

On a linux system use the mbsystem shared library, e.g.:

        GMT_CUSTOM_LIBS = /usr/local/lib/mbsystem.so

 
MB-SYSTEM AUTHORSHIP

David W. Caress




  Monterey Bay Aquarium Research Institute



Dale N. Chayes




  Center for Coastal and Ocean Mapping




  University of New Hampshire



Christian do Santos Ferreira




  MARUM - Center for Marine Environmental Sciences




  University of Bremen

 
OPTIONS

-G

<objfile>



Output topography OBJ format file.
Default is to add ".obj" suffix to the input grid
file name (replacing ".grd" suffix if possible).
-R

Specify the min/max coordinates of your data region in user units.



Use dd:mm[:ss] for regions given in arc degrees, minutes [and seconds].



Use -R<xmin/xmax/ymin/ymax>+<unit> for regions given in projected coordinates.
with <unit> selected from e|f|k|M|n|u.



Use [yyy[-mm[-dd]]]T[hh[:mm[:ss[.xxx]]]] format for time axes.
Append +r if -R specifies the coordinates of the lower left and
upper right corners of a rectangular area.



Use -R<gridfile> to use its limits (and increments if applicable).



Use -Rg and -Rd as shorthands for -R0/360/-90/90 and -R-180/180/-90/90.
Derive region from closed polygons from the Digital Chart of the World (DCW):
Append a comma-separated list of ISO 3166 codes for countries to set region, i.e.,
<code1>,<code2>,... etc., using the 2-character ISO country codes (see pscoast -E+l for list).
To select a state of a country (if available), append .state, e.g, US.TX for Texas.
To select a whole continent, give =AF|AN|AS|EU|OC|NA|SA as <code>.



Use +r to modify the region from polygon(s): Append <inc>, <xinc>/<yinc>, or <winc>/<einc>/<sinc>/<ninc>
to round region to these multiples; use +R to extend region by those increments instead [0].



Or use -R<code><x0>/<y0>/<n_columns>/<n_rows> for origin and grid dimensions, where
<code> is a 2-char combo from [T|M|B][L|C|R] (top/middle/bottom/left/center/right)
and grid spacing must be specified via -I<dx>[/<dy>] (also see -r).
-V

Change the verbosity level (currently v). Choose among 6 levels; each level adds more messages:

     q - Quiet, not even fatal error messages.

     n - Normal verbosity: only error messages.

     c - Also produce compatibility warnings [Default when no -V is used].

     v - Verbose progress messages [Default when -V is used].

     l - Long verbose progress messages.

     d - Debugging messages.

 
EXAMPLES

Suppose we have obtained a GRD file called ZTopo.grd that contains seafloor
topography. In order to obtain an OBJ file named ZTopo.obj, we use:




  gmt mbgrd2obj ZTopo.grd -Vl



The output to the shell is:

  mbgrd2obj [INFORMATION]: Processing input grid

  mbgrd2obj [INFORMATION]: Reading grid from file ZTopo.grd

  mbgrd2obj [INFORMATION]: Set boundary condition for all edges: natural

  mbgrd2obj [INFORMATION]: Set boundary condition for left   edge: natural

  mbgrd2obj [INFORMATION]: Set boundary condition for right  edge: natural

  mbgrd2obj [INFORMATION]: Set boundary condition for bottom edge: natural

  mbgrd2obj [INFORMATION]: Set boundary condition for top    edge: natural

  mbgrd2obj [INFORMATION]: 285087 vertices output

  mbgrd2obj [INFORMATION]: 562024 triangles output

 
SEE ALSO

mbsystem(1), mbgrid(1), mbm_grdtiff(1), gmt(1)

 
BUGS

Let us know.



 
Index

NAME

VERSION

SYNOPSIS

DESCRIPTION

MB-SYSTEM AUTHORSHIP

OPTIONS

EXAMPLES

SEE ALSO

BUGS