add examples to help pages

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@41023 15284696-431f-4ddb-bdfa-cd5b030d7da7

visualization/wximgview/wximgview.html

@@ -11,11 +11,31 @@ The display driver must be configure to map the file, with
 <em>GRASS_PNG_MAPPED=TRUE</em>. This ensures that the file will remain
 a constant size, rather than being truncated whenever it is updated.
 
+
+<h2>EXAMPLE</h2>
+
+(bash shell syntax)
+<div class="code"><pre>
+export GRASS_PNGFILE=map.bmp
+export GRASS_WIDTH=640
+export GRASS_HEIGHT=480
+export GRASS_RENDER_IMMEDIATE=cairo
+export GRASS_PNG_MAPPED=TRUE
+export GRASS_PNG_READ=TRUE
+
+d.erase
+wximgview $GRASS_PNGFILE percent=50 &
+d.rast elevation.dem
+d.vect roads
+</pre></div>
+
+
 <h2>SEE ALSO</h2>
 
 <em>
-<a href="pngdriver.html">PNG driver</a>
-<a href="cairodriver.html">cairo driver</a>
+<a href="pngdriver.html">PNG driver</a><br>
+<a href="cairodriver.html">cairo driver</a><br>
+<a href="ximgview.html">ximgview</a>
 </em>
 
 

visualization/ximgview/ximgview.html

@@ -11,11 +11,31 @@ The display driver must be configure to map the file, with
 <em>GRASS_PNG_MAPPED=TRUE</em>. This ensures that the file will remain
 a constant size, rather than being truncated whenever it is updated.
 
+
+<h2>EXAMPLE</h2>
+
+(bash shell syntax)
+<div class="code"><pre>
+export GRASS_PNGFILE=map.bmp
+export GRASS_WIDTH=640
+export GRASS_HEIGHT=480
+export GRASS_RENDER_IMMEDIATE=PNG
+export GRASS_PNG_MAPPED=TRUE
+export GRASS_PNG_READ=TRUE
+
+d.erase
+ximgview $GRASS_PNGFILE percent=50 &
+d.rast elevation.dem
+d.vect roads
+</pre></div>
+
+
 <h2>SEE ALSO</h2>
 
 <em>
-<a href="pngdriver.html">PNG driver</a>
-<a href="cairodriver.html">cairo driver</a>
+<a href="pngdriver.html">PNG driver</a><br>
+<a href="cairodriver.html">cairo driver</a><br>
+<a href="wximgview.html">wximgview</a>
 </em>