[GRASS-SVN] r61097 - grass/trunk/raster/r.horizon

[svn_grass at osgeo.org]

Author: zarch
Date: 2014-07-01 02:27:17 -0700 (Tue, 01 Jul 2014)
New Revision: 61097

Modified:
   grass/trunk/raster/r.horizon/r.horizon.html
Log:
r.horizon: Update the manual page

Modified: grass/trunk/raster/r.horizon/r.horizon.html
===================================================================
--- grass/trunk/raster/r.horizon/r.horizon.html	2014-07-01 09:24:45 UTC (rev 61096)
+++ grass/trunk/raster/r.horizon/r.horizon.html	2014-07-01 09:27:17 UTC (rev 61097)
@@ -35,24 +35,33 @@
 
 
 <h3>Input parameters:</h3>
-<p>The <i>elev_in</i> parameter is an input elevation raster map. If
+<p>The <i>elevation</i> parameter is an input elevation raster map. If
 the buffer options are used (see below), this raster should extend
 over the area that accommodate the presently defined region plus
 defined buffer zones. 
 
-<p>The <i>horizon_step</i> parameter gives the angle step (in degrees)
+<p>The <i>step</i> parameter gives the angle step (in degrees)
 between successive azimuthal directions for the calculation of the
-horizon. Thus, a value of 5 for the <i>horizon_step</i> will give a total of
+horizon. Thus, a value of 5 for the <i>step</i> will give a total of
 360/5=72 directions (72 raster maps if used in the raster map mode). 
 
+<p>The <i>start</i> parameter gives the angle start (in degrees)
+for the calculation of the horizon. The default value is 0.
+
+<p>The <i>end</i> parameter gives the angle end (in degrees)
+for the calculation of the horizon. The end point is omitted!
+So for example if we run r.horizon with step=10, start=30 and end=70
+the raster maps generated by r.horizon will be only for angles:
+30, 40, 50, 60. The default value is 360.
+
 <p>The <i>direction</i> parameter gives the initial direction of the
 first output. This parameter acts as an direction angle offset. For
 example, if you want to get horizon angles for directions 45 and 225
-degrees, the <i>direction</i> should be set to 45 and <i>horizon_step</i> to
+degrees, the <i>direction</i> should be set to 45 and <i>step</i> to
 180. If you only want one single direction, use this parameter to
-specify desired direction of horizon angle, and set the <i>horizon_step</i>
+specify desired direction of horizon angle, and set the <i>step</i>
 size to 0 degrees. Otherwise all angles for a given starting <i>direction</i>
-with step of <i>horizon_step</i> are calculated.
+with step of <i>step</i> are calculated.
 
 <p>The <i>distance</i> controls the sampling distance step size for the
 search for horizon along the line of sight. The default value is 1.0
@@ -87,10 +96,11 @@
 buffer parameters influence only size of the read elevation map,
 while the analysis in the raster mode will be done only for the
 area specified by the current region definition.
-<p>The <i>horizon </i>parameter gives the prefix of the output
+
+<p>The <i>basename</i> parameter gives the basename of the output
 horizon raster maps. The raster name of each horizon direction
-raster will be constructed as <i>horizon_</i>NNN , where NNN counts
-upwards from 0 to total number of directions. If you use <b>r.horizon</b>
+raster will be constructed as <i>basename_</i>ANGLE, where ANGLE
+is the angle in degrees with the direction. If you use <b>r.horizon</b>
 in the single point mode this option will be ignored. 
 
 <p>The <i>output</i> parameter allows to save the resulting horizon
@@ -116,7 +126,7 @@
 the region (see also the <i>bufferzone,e_buff</i>, <i>n_buff</i>,
 <i>s_buff</i>, and <i>w_buff</i>). The the number of lines of sight (azimuth 
 directions) is determined from the <i>direction</i> and
-<i>horizon_step</i> parameters. The method takes into account the curvature
+<i>step</i> parameters. The method takes into account the curvature
 of the Earth whereby remote features will seem to be lower than they
 actually are. It also accounts for the changes of angles towards
 cardinal directions caused by the projection (see above). 
@@ -131,17 +141,17 @@
 Single point mode (output of horizon angles CCW from East):
 <div class="code"><pre>
 # determine horizon angle in 225 degree direction:
-r.horizon elev_in=elevation direction=215 horizon_step=0 bufferzone=200 \
+r.horizon elevation=elevation direction=215 step=0 bufferzone=200 \
     coordinate=638871.6,223384.4 maxdistance=5000
 
 # determine horizon values starting at 90 deg (North), step size of 5 deg:
 # save result in CSV file
-r.horizon elev_in=elevation direction=90 horizon_step=5 bufferzone=200 \
+r.horizon elevation=elevation direction=90 step=5 bufferzone=200 \
     coordinate=638871.6,223384.4 maxdistance=5000 output=horizon.csv
 
 # test point near high way intersection
 g.region n=223540 s=220820 w=634650 e=638780 res=10 -p
-r.horizon elev_in=elevation direction=0 horizon_step=5 bufferzone=200 \
+r.horizon elevation=elevation direction=0 step=5 bufferzone=200 \
     coordinate=636483.54,222176.25 maxdistance=5000 -d output=horizon.csv
 </pre></div>
 
@@ -157,8 +167,9 @@
 Raster map mode (output maps "horangle*" become input for <em>r.sun</em>):
 <div class="code"><pre>
 # we put a bufferzone of 10% of maxdistance around the study area
-r.horizon elev_in=elevation horizon_step=30 bufferzone=200 horizon=horangle \
-    maxdistance=5000
+# compute only direction between 90 and 270 degrees
+r.horizon elevation=elevation step=30 start=90 end=300 \
+    bufferzone=200 basename=horangle maxdistance=5000
 </pre></div>