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<h2>Name</h2>
<B><tt>r.refine</tt></B>: scalable raster-to-TIN simplification.
<p><h2>Description</h2>
<tt>r.refine</tt> takes as input a grid DEM and an error margin and
simplifies it to the desired accuracy into a TIN. The resulting TIN is
guaranteed to be within error epsilon from the grid.
<H2>SYNOPSIS</H2>
<pre>
r.refine -help
Description:
r.refine: scalable raster-to-TIN simplification.
Usage:
r.refine [-dnr] grid=name [epsilon=value] [tin=name]
[output_sites=name] [output_vect=name] [memory=value]
Flags:
-d Do NOT use Delaunay triangulation
-n Include nodata points (in simplification)
-r Render TIN in OpenGL
Parameters:
grid Input raster
epsilon Error threshold, in percentage of max elevation
default: 1.0
tin Output TIN file
default: output.tin
output_sites Name of output sites file.
default: NULL
output_vect Name of output vector file.
default: NULL
memory Main memory size (in MB)
default: 500
</pre>
<p>The user has to specify an error (<tt>epsilon=xxx</tt>); by default
this is 1. Point are be dropped from the grid so that the output TIN
approximates the grid within error <tt>epsilon</tt>. The smaller the
epsilon, the bigger, and more accurate, the TIN.
<p>The output TIN is output in internal TIN format (the name of the
tin can be set by the user with <tt>tin=xxx</tt>); It can be also
output as sites, if the user specifies a sites filename
(<tt>output_sites=xxx</tt>), or as a vector
(<tt>output_vect=xxx</tt>).
<p> The user can specify a main memory size (in MB) to be used by
<tt>r.refine</tt>. The program will at all times use this much memory,
and the virtual memory system will not be in use. In practice the
<tt>mem=value</tt> should be an underestimate of the amount of available
(free) main memory on the machine.
<H2>Examples</H2>
<pre>
r.refine grid=xxx.elev eps=10 tin=xxx.tin output_vect=xxx.vect mem=600
</pre>
<H2>NOTES</H2>
The folder comes with several Makefiles, including a GMakefile for
Grass 5.3. It can be compiled standalone, or under GRASS. To compile
standalone:
<pre>
cd r.refine
make -f Makefile.mac
</pre>
Then run from the command line:
<pre>
./r.refine
</pre>
<p>To compile under GRASS:
<pre>
/path/to/gmake
</pre>
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<address></address>
<!-- hhmts start --> Last modified: Fri Sep 21 14:21:29 EDT 2007 <!-- hhmts end -->
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