Yes, this was possible at a certain time via the script. Now you should be able to use it via a java command directly:
cd graphhopper
git checkout 0.11
mvn clean install
java -cp tools/target/graphhopper-tools-0.13-SNAPSHOT-jar-with-dependencies.jar com.graphhopper.ui.MiniGraphUI graph.location=graph-cache datareader.file=berlin-latest.osm.pbf graph.flag_encoders=car
Or if you are interested in latest cutting edge version using vector tiles directly from GraphHopper storage (from few hours ago 
), then you can try this branch: https://github.com/graphhopper/graphhopper/tree/experimental-mvt with the help of a special leaflet plugin.