Rename classic r.buffer back to its original name, rename the python

version to "lowmem". Describe the alternatives in the help pages.
The classic C version runs more than 40x faster and memory only becomes 
an issue when the map size is abnormally massive. (32000x32000 cells on
a machine with 1 GB RAM, 90000x90000 cells on a machine with 8 GB RAM).


git-svn-id: https://svn.osgeo.org/grass/grass/trunk@52172 15284696-431f-4ddb-bdfa-cd5b030d7da7

raster/r.buffer/Makefile

@@ -1,6 +1,6 @@
 MODULE_TOPDIR = ../..
 
-PGM = r.buffer2
+PGM = r.buffer
 
 LIBES = $(RASTERLIB) $(GISLIB)
 DEPENDENCIES = $(RASTERDEP) $(GISDEP)

scripts/r.buffer/r.buffer.html → raster/r.buffer/r.buffer.html

@@ -29,6 +29,7 @@ <h2>DESCRIPTION</h2>
 </pre></div>
 <br>
 
+
 <h2>NOTES</h2>
 
 The user has the option of identifying up to 250 continuous zones.
@@ -67,6 +68,14 @@ <h2>NOTES</h2>
 The <b>-z</b> flag can be used to ignore raster values of zero instead of NULL
 values in the input raster map.
 <p>
+When working with massive raster regions consider the <em>r.buffer.lowmem</em>
+module if RAM use becomes a problem. The lowmem version can be &gt; 40x slower,
+but will work with minimal memory requirements. The classic <em>r.buffer</em>
+should be able to deal with raster maps of 32000x32000 size on a system with
+1 GB RAM, and rasters of 90000x90000 on a system with 8 GB RAM without going
+into swap.
+
+
 <h2>EXAMPLE</h2>
 
 In the following example, the buffer zones would be (in the default units
@@ -89,10 +98,12 @@ <h2>EXAMPLE</h2>
       6       400-500 meters
 </pre></div>
 
+
 <h2>SEE ALSO</h2>
 
 <em>
 <a href="g.region.html">g.region</a><br>
+<a href="r.buffer.lowmem.html">r.buffer.lowmem</a><br>
 <a href="r.cost.html">r.cost</a><br>
 <a href="r.mapcalc.html">r.mapcalc</a><br>
 <a href="r.reclass.html">r.reclass</a><br>

scripts/Makefile

@@ -25,7 +25,7 @@ SUBDIRS = \
 	i.tasscap \
 	m.proj \
 	r.blend \
-	r.buffer \
+	r.buffer.lowmem \
 	r.colors.stddev \
 	r.fillnulls \
 	r.grow \

scripts/r.buffer/Makefile → scripts/r.buffer.lowmem/Makefile

@@ -1,6 +1,6 @@
 MODULE_TOPDIR = ../..
 
-PGM = r.buffer
+PGM = r.buffer.lowmem
 
 include $(MODULE_TOPDIR)/include/Make/Script.make
 

raster/r.buffer/r.buffer2.html → scripts/r.buffer.lowmem/r.buffer.lowmem.html

@@ -1,10 +1,21 @@
 <h2>DESCRIPTION</h2>
 
-<em>r.buffer</em> creates a new raster map layer showing
+<em>r.buffer.lowmem</em> creates a new raster map layer showing
 buffer (a.k.a. "distance" or "proximity") zones around all
 cells that contain non-NULL category values in an existing
 raster map layer.  The distances of buffer zones from cells
-with non-zero category values are user-chosen.  Suppose,
+with non-zero category values are user-chosen.
+
+<p>
+This is the low-memory alternative to the classic <em>r.buffer</em>
+module. It is much slower than the classic version, but will
+run on massive raster maps without using a lot of RAM. If your
+raster map is larger than 32000x32000 cells on a system with
+1 GB of RAM, or larger than 90000x90000 cells on a system with
+8 GB of RAM, consider using this module.
+
+<p>
+Suppose,
 for example, that you want to place buffer zones around
 roads.  This program could create the raster map layer
 shown below on the right based on road information
@@ -93,7 +104,9 @@ <h2>SEE ALSO</h2>
 
 <em>
 <a href="g.region.html">g.region</a><br>
+<a href="r.buffer.html">r.buffer</a><br>
 <a href="r.cost.html">r.cost</a><br>
+<a href="r.grow.distance.html">r.grow.distance</a><br>
 <a href="r.mapcalc.html">r.mapcalc</a><br>
 <a href="r.reclass.html">r.reclass</a><br>
 <a href="v.buffer.html">v.buffer</a>
@@ -107,5 +120,8 @@ <h2>AUTHORS</h2>
 <br>
 James Westervelt, U.S. Army Construction Engineering 
 Research Laboratory
+<br>
+Low-memory Python version by Glynn Clements
 
-<p><i>Last changed: $Date$</i>
+<p>
+<i>Last changed: $Date$</i>

scripts/r.buffer/r.buffer.py → scripts/r.buffer.lowmem/r.buffer.lowmem.py

@@ -2,9 +2,9 @@
 #
 ############################################################################
 #
-# MODULE:	r.buffer
+# MODULE:	r.buffer.lowmem
 # AUTHOR(S):	Glynn Clements
-# PURPOSE:	Replacement for r.buffer using r.grow.distance
+# PURPOSE:	Low-memory replacement for r.buffer using r.grow.distance
 #
 # COPYRIGHT:	(C) 2008, 2010 by Glynn Clements
 #