Update 'README.md'

README.md

@@ -45,7 +45,7 @@ Doing so will avoid having a messy `inputs` folder due to region-specific files
 
 ### Generating maps
 
-Only manual generation is supported as of now:
+Only manual generation using `osmosis` is supported currently.
 
 #### Mapsforge file:
 
@@ -68,6 +68,22 @@ bin/osmosis --rb inputs/bretagne/bretagne-latest.osm.pbf  \
     --osm2graph file=outputs/rennes.mapgr writer=insa2018 map-id=0x235
 ```
 
+#### Combining generations
+
+You can combine both generation using the `--tee` option of `osmosis`:
+
+```bash
+# The order is important! You do not want to use osmosis filters/bounding-box before mapfile-writer.
+bin/osmosis --rb inputs/bretagne/bretagne_merge.pbf --tee \
+    --mapfile-writer file=outputs/morbihan.mapfg bbox=$(cat inputs/bbox/morbihan.bbox) threads=2 \
+    --bounding-box $(cat inputs/bbox/morbihan.bbox | tr "," " " | xargs printf "bottom=%f left=%f top=%f right=%f") completeWays=yes
+    --used-node --tf reject-relations --tf accept-ways highway=(cat inputs/highway-filter.cmd) natural=coastline
+    --osm2graph file=ouputs/morbihan.mapgr writer=insa2018 map-id=0x400
+```
+
+**Note**: You can add logging by specifying `--lp` between `osmosis` tasks.
+
+
 ### Bounding box
 
 Bounding box files should contain a single line with comma-separated (**without spaces**) values: