|This article is about the current version of DF.|
The world painter tool allows you to paint features onto a map, that is then used when generating a world. It is very difficult to use properly, and tends to result in endless rejected worlds, unless you loosen or remove the restrictions placed on biomes and civilizations in the advanced settings. That being said, it is also a very powerful tool, and allows you to generate worlds more to your liking.
The game refers to this tool as "Set Preset Field Values".
To start the world painter, you have to start Dwarf Fortress, select the "Design New World With Advanced Parameters" option, then hit to editing the advanced parameters and finally hit to open world painter ("Set Preset Field Values"). Unlike most other aspects of Dwarf Fortress, the world painter requires use of the mouse. There is no keyboard-equivalent way to paint parameters.
The interface is reasonably simple. Simply left click on a tile and the settings on the right side of the screen with be applied to that tile. To move the view, right click and your active tile will be centered at cursor's location. To make a tile active, paint something there or just press . You can left click on any of the text on the right to change the setting it represents. By clicking on the title of one of the settings, or the <View> text to the right of it, you can replace the default view with a view representing just that parameter (You can return to the normal view by pressing . By clicking the text "brush = ____", you can change the value of that parameter. Clicking on the text "painting" will toggle whether the parameter is painted when you click on a tile, and clicking on "Will Be Saved", will allow the world generator to deal with that parameter, instead of using what was painted.
It's easier to start with elevation by setting painting on only there, and continue with rain and drainage together.
Rainfall goes from 0-100, with 0 making dry areas
Elevation goes from 1-400, with anything below 100 being water, and with 300+ being mountain.
Temperature goes from 25-75, and has little visible effect in the editor, with the exception of creating glaciers and tundra near the edges.
Drainage goes from 0-100, with 0 making areas that retain water, such as swamps and deserts, and 100 making areas that lose any rainfall that comes, such as forests and badlands.
Savagery goes from 0-100, and has no effect on the land, but influences the wildlife that will spawn there.
Volcanism goes from 0-100, with 0 never having volcanoes and 100 always having them, unless a maximum is otherwise specified in the advanced optionsVerify.
For more information, see the Biome page.
Resetting the World Painter
This is a link to the relevant thread on the Bay12 forums.
If you have inadvertently entered and exited the World Painter and are receiving world rejections, re-enter the world painter and click "Will be saved" to toggle the parameters to "Randomize at gen".