SETUP: Wrote paragraph about how to start the web mapper.

SETUP.md

@@ -90,7 +90,35 @@ can also run it as a nightly cron job to dedupe the map on a regular basis.
 
 
 ## Start the web server mtwebmapper
-**TODO: Write me!**
+
+This web server serves the Leaflet compatibles to the browser and is contacted by `mtredisalize`
+if something in the world has changed. In this case the corresponding map tiles are re-generated
+in the background. To start `mtwebmapper` use:
+
+    GOMAXPROCS=3 mtwebmapper           \
+      -colors=/path/to/your/colors.txt \
+      -web-host=""                     \
+      -map=/path/to/your/map           \
+      -web=/path/to/your/static/web    \
+      -redis-host=localhost            \
+      -workers=2
+
+For the `colors=` options applys the same as said above. The `web-host=` is the interface the
+server ist listening on. `""` means all interfaces. The port defaults to 8808.
+For a productive setup you may consider running it behind a reverse proxy.  
+`-map=` has to be the same path as used by `mtseeder`.  
+`-web=` is the path to the static web data (Leaflet, HTML, CSS, etc.). You can take it
+from the [repository](https://bitbucket.org/s_l_teichmann/mtsatellite/src/default/cmd/mtwebmapper/web/)
+
+To fetch the block data from the `mtredisalize` you have to use the option `redis-host=`. If
+you omit this then there will be no background job to re-generate the map. This is useful
+if you want to serve a map that is only generated once whith `mtseeder`.
+
+To see all the available options use `mtwebmapper --help`.
+
+The `GOMAXPROCS=`/`-workers=` setting has to be adjusted to your system capacity. Do not
+give to much ressources to this if you planning to run the mapping webserver on the
+same machine as the Minetest server.
 
 ## Configure and restart the Minetest server
 **TODO: Write me!**