Building Rules¶
A Building Rules asset is a reusable building recipe: its volumes, walls, roofs and floor counts. Give the same rules to many buildings and they share a style, while each footprint still gets its own shape.
Creating rules¶
- From a building you've set up: right-click the Building component and choose Create Building Rules From Current Setup..., then pick where to save the asset.
- From scratch: Assets > Create > World Toolkit > Buildings > Rules.
Rules made from a building capture what it generates now: its volumes (or those of its Rules Override), and its current floor and subfloor counts as single entries. A volume with its own Footprint Spline keeps that shape as an Explicit Footprint, since an asset can't point at a spline in the scene: its knots become corners joined by straight walls.
What rules contain¶
- Volumes
- The same volume setup as on a building. See Volumes.
- Floor Chances
- A list of floor ranges, each with a Chance. A building using these rules rolls one entry, then a floor count inside its range, so a street of buildings with the same rules varies in height. Turn on Random in an entry to give it a minimum and a maximum. Chances are weights: an entry with twice the chance of another is picked twice as often. With no entries, buildings get one floor.
- Subfloor Chances
- The same for floors below ground (basements, foundations). With no entries, buildings get none.
The floor chart¶
Above the Floor Chances list, a chart shows what the entries add up to:
- a summary with the average and the range of floor counts,
- a bar with each entry's share of the chances. Drag the divider between two entries to move chance from one to the other, without changing the others (only with a single asset selected),
- a histogram of how likely each floor count is, with the subfloor counts hanging below it. Hover a column to read its chance.
If every chance is 0, the first entry is always used, and the summary says so.
Previewing rules¶
The Building Preview at the bottom of the inspector generates the rules on a test footprint, rolling floors and chances from the preview seed. The asset's thumbnail in the Project window shows the same building.
| Control | What it does |
|---|---|
| Iso | Uses an orthographic camera instead of a perspective one. |
| Wire | Shows the wireframe of the generated mesh. |
| Shape menu | The test footprint: Rectangle, L Shape, U Shape, Octagon or Angled. Concave and angled shapes show how walls and corners behave on inside corners and odd angles. |
| W and D | Width and depth of the test footprint, in meters. |
| Seed and Reroll | The seed the preview rolls with. Reroll picks a random one. |
| Grid | Shows four seeds side by side to compare variations. |
| Reset | Resets the preview camera. Drag in the preview to orbit, scroll to zoom. |
The top of the inspector lists problems in the volumes: volumes without walls, wall entries without a wall asset or with a Chance of 0, walls and roofs that have issues of their own, and corners only some walls of a volume define. Click one to jump to its field.
Using rules¶
There are two ways to give rules to a building, and they behave differently when you edit the rules later.
- As a Rules Override
- Set the building's Rules Override. The building generates straight from the rules, and editing the rules regenerates it. Unlocked floor and subfloor counts are rolled from the rules with the building's seed.
- As a copy
-
These copy the rules' volumes into the building and roll its floor counts:
- New Building Defaults in the Buildings panel, for every new building you draw,
- Apply to Selected in the Buildings panel, for the selected buildings,
- Building Rule Chances on building blocks, for the buildings of each lot.
The building's volumes are its own afterwards, so you can change them on that building alone.
Copies don't follow the rules
Editing a rules asset only updates the buildings that use it as their Rules Override. Buildings that got a copy keep it: apply the rules to them again, or set the rules as their Rules Override. Walls and roofs are shared either way, so editing a Volume Wall or Roof asset updates every building that uses it.
A building can still keep its own floor count: enable Lock Floors or Lock Subfloors on it.