Draft newgrf docs https://wiki.openttd.org/Frosch/NotRoadTypes
OpenTTD builds and forked repo
https://www.openttd.org/en/download-ratt
https://github.com/andythenorth/NotRoad ... tram-types
NML fork
https://github.com/andythenorth/nml-and ... tRoadTypes
Windows binary for NML: http://devs.openttd.org/~frosch/nml-nrt ... -win32.zip
Patched Road Hog grf attached, with 2 road types and 2 tram (light rail) types, and some vehicles to suit each.
frosch and Wolf patched OpenTTD, I patched a bit of nml and the Road Hog grf. Thanks also to Alberth and Eddi amongst others

This isn't done-done-done, but a lot of it is there.
- grfcodec appears to work as expected with no changes needed
- (nfo)renum does not work currently, and as yet, there is currently plan to fix it
- no support
- GUI icons only present when using original baseset graphics, OpenGFX and other basesets will need updated
- it will break your savegames
- don't load the patched Road Hog grf in vanilla OpenTTD, it will report an error
- there's no timeline for moving this to trunk, asking will only slow it down
