Inspired by a Post by orudge » 15 Mar 2013 09:05. Checked for relevance and added to on 03 Aug 2026.
For any new users who are confused about NewGRFs and what they do, this post by FLHerne may be of some use:
NewGRFs are not necessarily just ‘art packages’; they can do a lot beyond the visual and many do not even even contain art.
What NewGRFs Do
Depending on the GRF, they can a number of different things:
Add Vehicle Types
- These often have more features than the default vehicles, for example:
- Support for non-default cargo types.
- Speed limits for wagons, and/or locomotives.
- Support for ‘autorefitting’in stations.
- Different graphics depending on date, wagon type, etc.
- Maximum ranges for aircraft.
- Add trams that are not included by default.
- Most vehicle sets can be used together, but not that they might not be ‘balanced’ – the running costs and maximum speeds might make vehicles from one set preferable. Many such sets disable the default vehicles.
- There’s a slight variant:
- Modify the existing vehicles directly, changing the stats or introduction dates.
- There are not many of these, and they can be problematic when used with other GRFs affecting the default vehicles.
Modify Infrastructure
- Add new types of town buildings.
Mostly just for aesthetics, but it is possible for such sets to control the rate of town growth.
These can be used together, but sets trying to do ‘clever stuff’, e.g. TaI, will not be able to do that when used with others. - Add station types.
These are mostly just artistic. Some display the amount and type of cargo waiting, which can be useful.
All can be used together, I believe. - Add new Railway types.
This includes tracks with speed limits, third-rail electrified tracks, or narrow gauge types.
Most such GRFs remove the default game’s Monorail and MagLev tracks in the process.
These can be used together to some extent, but there is a restrictive limit on the number of different track types that can be defined. If you use a combination of sets that combined provide >16 types of track, it will not work properly. - Change Road Appearance.
Some sets may display different road graphics depending on date with No game play effect.
These cannot be used together. They do not alter the road surface on bridges.
A variation on this are tram track GRFs that change the appearance of Tramways.* - Change Bridge Types
These replace the default bridge types, and can have slightly more types of bridges than normal.
They cannot be used together. The road surface on the bridges does not change to match road sets; some bridge GRFs have alternate versions to match various road sets. - Replace airport and dock graphics; allow rotatable airports.
For dock graphics the last one in the NewGRF Active List wins.
Airports have nor changed much inn a while do to the difficult with programming them. Most related GRFs provide graphics as objects to make airports more realistic. They do not change the functionality or airport types.
Modify Industries and Cargo Types
- GRFs can modify the properties of the default industries and materials they supply or manufacture.
They could instead define additional industries or replacements.
These often have different mechanics to the default ones, for example FIRS has a ‘supply’ mechanic, and ECS and TaI both have a ‘stockpiling’ system. Never use multiple industry GRFs together unless they are specifically designed to work together. (You will likely get a warning)
Modify Landscape
- Change the appearance of landscape tiles.
What it says on the tin, really. For obvious reasons, one such GRF msy be used at a time. - Add New Objects.
Purely for looking at (eye candy, so called), they add build-able tiles under the Landscaping toolbar. Harbor walls, trees, wind turbines, flocks of seagulls, etc. These can all be used together.
Modify Base Costs
- This allows changing the price of terra-forming, building, bribing the town local authority, etc. The effects of these are cumulative.
Add Town Names
- By adding a Town Name GRF you can set a new game to use Australian town names, for example instead of the default.
The NewGRF needs to be active and then in a New Game you select it. It should be automatically set but check.)
Set Parameters
- Depending on the GRF, you can override normal game settings affecting time, speed, cost, distance, etc. It is recommended you check the documentation for details and this forum for players feedback and tips.
Precaution and Advice
Remember that a single GRF can do any combination of these things – for example, several sets that add rail stations also replace dock and shipyard graphics, some town sets replace road and bridge graphics. There is one train set (NARS) that actually defines a cargo type and has been known to conflict with ECS industries. Most are reasonably self-contained, however.
More from Owen Rudge: