Add a column

A column is a vertical member at one point. You give its position and its section. Its height is the storey height.

Before you start

You have a session from Start a building.

Write the column

This column is at [0, 0] and has a section of 0.3 by 0.3 metres.

import {
  ColumnShape,
  type BmColumn,
  type BuildingSession,
  type ElementListCommand,
} from '@opengeometry/floorkit';

export const cornerColumn: BmColumn = {
  id: 'column-a1',
  shape: ColumnShape.RECTANGULAR,
  center: [0, 0],
  baseOffset: 0,
  width: 0.3,
  depth: 0.3,
};

Add it to the storey

A column is an entry in the columns list of its storey.

export function addColumn(session: BuildingSession): void {
  session.apply(
    {
      kind: 'add-element',
      buildingId: 'building',
      storeyId: 'ground',
      list: 'columns',
      element: cornerColumn,
    },
    session.revision,
  );
}

The add-element command adds the column to the list, and the session builds it. You keep the session and its undo history. The command rejects an id that the list has.

Sections

`shape`	You give
`ColumnShape.RECTANGULAR`	`width` and `depth`
`ColumnShape.CIRCULAR`	`radius`
`ColumnShape.CUSTOM`	`customProfile`, your own outline

In a JSON file, write the shape as text: "RECTANGULAR".

Rules

center is [x, z] in metres. rotation turns the section, in degrees.
baseOffset is the distance from the storey elevation to the base of the column.
The height is the storey height. Set height to change it.
A column is geometry. Floorkit does not calculate loads.

A grid of columns

Make one entry for each position. Give each column its own id.

export function columnGrid(columns: number, rows: number, spacing: number): BmColumn[] {
  return Array.from({ length: columns * rows }, (_, index) => ({
    ...cornerColumn,
    id: `column-${index + 1}`,
    center: [(index % columns) * spacing, Math.floor(index / columns) * spacing],
  }));
}

A grid is a change of many elements at one time. Send it as one batch. The session applies the commands of a batch in order and builds one time. This batch removes the corner column and adds the six columns of the grid.

export function addColumnGrid(session: BuildingSession): void {
  const grid: ElementListCommand[] = columnGrid(3, 2, 3).map((column) => ({
    kind: 'add-element',
    buildingId: 'building',
    storeyId: 'ground',
    list: 'columns',
    element: column,
  }));
  session.apply(
    {
      kind: 'batch',
      commands: [
        {
          kind: 'remove-element',
          buildingId: 'building',
          storeyId: 'ground',
          list: 'columns',
          elementId: cornerColumn.id,
        },
        ...grid,
      ],
    },
    session.revision,
  );
}

One batch is one step: one undo takes the grid away. If one command of the batch fails, the session changes nothing. See A batch of commands.

Define a room

Give a name and an area to a space.

Column API

See each option of a column.

Documentation

Before you start

Write the column

Add it to the storey

Sections

Rules

A grid of columns

Next

Define a room

Column API

​Before you start

​Write the column

​Add it to the storey

​Sections

​Rules

​A grid of columns

​Next

Define a room

Column API

Before you start

Write the column

Add it to the storey

Sections

Rules

A grid of columns

Next