Generates graphs for rails classes
Produce a models diagram to the file models.dot
railroad -o models.dot -M
Models diagram with all classes showing inheritance relations
railroad -a -i -o full_models.dot -M
Model diagram in SVG format
railroad -M | dot -Tsvg > models.svg
Controller diagram in PNG format
railroad -C | neato -Tpng > controllers.png
Other options
-b brief info, not class attributes