Introducing an open-source, accessible, simple, minimalistic file format for BIM. Built to be easy to read and write.

Created by BIM developers for BIM developers.

An idiot admires complexity, while a genius appreciates simplicity - Terry Davis

Website: https://www.dotbim.net

Quick introduction video: https://www.youtube.com/watch?v=RSV-0-UrzhQ

To see much more extended comparison check out Dion's comparison here: paireks#8

If you're a developer, check out this document: https://github.com/paireks/dotbim/blob/master/DeveloperTips.md

• C# library: you're looking at it right now ;)
• Python library: dotbimpy - https://github.com/paireks/dotbimpy
• Grasshopper plugin: dotbimGH - https://github.com/paireks/dotbimGH
• dotbim-ifc, converts to and from IFC and dotbim: https://github.com/Moult/dotbim-ifc, Author: Dion Moult
• Online 3d Viewer, supports .bim files and converts to other file formats: https://3dviewer.net/, Authors: Viktor Kovacs, Agnes Gaschitz
• Blender add-on: dotbim-blender, imports and exports .bim files https://github.com/paireks/dotbim-blender, Author: Nathan Hild
• dotbim-io-dxf, converts to and from 3d DXF files: https://github.com/Gorgious56/dotbim_io_dxf, Author: Nathan Hild
• Typescript library: dotbim-ts - https://github.com/baid-group/dotbim-ts, Author: Maciej Lutostański
• Archicad addon: dotbim-archicad - https://github.com/kovacsv/dotbim-archicad, Author: Viktor Kovacs
• Revit detailed MEP to schematic 3d model - https://github.com/os4bim/dotbim, Author: Yoann Obry
• SketchUp add-on: https://github.com/MattiaBressanelli/import_dotbim, Author: Mattia Bressanelli

If you're building any app that will use .bim - let me know, I'll post it here :)

https://www.nuget.org/packages/dotbim/

It may require importing another nuget for Newtonsoft.Json library: https://www.nuget.org/packages/Newtonsoft.Json/13.0.1

• .bim
• License: MIT
• JSON structure
• x, y, z coordinates should be in meters
• Decimal point should be used
• JSON objects and properties should start with lowercase and with underscore as a seperator between words, e.g. schema_version

File contains 4 properties:

schema_version is the version of schema used in this file as string. Current one is "1.0.0".

mesh_id is integer >= 0 to reference this mesh later in element.

It is a big array of all coordinates of a mesh. It is structured in this way:

[X0, Y0, Z0, X1, Y1, Z1, X2, Y2, Z2, X3, Y3, Z3, ..., XN, YN, ZN]

Let's say our mesh is defined by 3 vertices: (0.0, 0.0, 0.0), (10.0, 0.0, 0.0) and (10.0, 5.0, 0.0), then your vertices_coordinates will look like this:

[0.0, 0.0, 0.0, 10.0, 0.0, 0.0, 10.0, 5.0, 0.0]

Later in faces_ids we refer to these vertices by their order.

It is a big array of ids (integers) that define all faces in a mesh. It is structured in this way:

[Face1_Id1, Face1_Id2, Face1_Id3, Face2_Id1, Face2_Id2, Face3_Id3, Face3_Id1, Face3_Id2, Face3_Id3, ..., FaceN_Id1, FaceN_Id2, FaceN_Id3]

If we'd like to create one-face mesh using vertices_coordinates from an example above, then it will look like this:

[0, 1, 2]

Pyramid example:

  "coordinates": [
    0.0,
    0.0,
    0.0,
    10.0,
    0.0,
    0.0,
    10.0,
    10.0,
    0.0,
    0.0,
    10.0,
    0.0,
    5.0,
    5.0,
    4.0
  ],
  "indices": [
    0,
    1,
    2,
    0,
    2,
    3,
    0,
    1,
    4,
    1,
    2,
    4,
    2,
    3,
    4,
    3,
    0,
    4
  ]

guid is a string that can be used for comparison of different elements.

"guid": "76e051c1-1bd7-44fc-8e2e-db2b64055068"

Vector places referenced mesh where it should be placed as an element. It should have 3 properties:

1. x (value)
2. y (value)
3. z (value)

  "vector": {
    "x": 9.9266016462536122,
    "y": 3.3910972817343494,
    "z": 52.239445879618685
  }

Rotation rotates referenced mesh how it should be rotated as element. It is a quaternion. It should have 4 properties:

1. qx (value) - first imaginary coefficient of the quaternion
2. qy (value) - second imaginary coefficient of the quaternion
3. qz (value) - third imaginary coefficient of the quaternion
4. qw (value) - real part of the quaternion

  "rotation": {
    "qx": 0.63979295771454925,
    "qy": 0.10626982147910254,
    "qz": -0.12472093047736807,
    "qw": -0.7508770776915008
  }

color should have 3 properties:

1. r (integer between 0-255) - red
2. g (integer between 0-255) - green
3. b (integer between 0-255) - blue
4. a (integer between 0-255) - alpha

  "color": {
    "r": 255,
    "g": 255,
    "b": 0,
    "a": 255
  }

Element type. It is a string that specifies what mesh represents. E.g. "Beam", "Plate".

"type": "Beam"

info is just a dictionary with string as key and value.

  "info": {
    "Name": "Teapot",
    "Price": "2.50$"
  }

.bim file format encourages users to link their data by attaching URLs inside properties of file or specific elements. E.g.:

  "info": {
    "Name": "Metal sheet roofing",
    "Catalogue": "https://pruszynski.com.pl/t-20-roof,prod,99,2294.php"
  }

Such functionality allows also to link one model with another as well. If you're interested in this kind of linking, check this separate document about it: https://github.com/paireks/dotbim/blob/master/LinkingData.md

If you'd like to read more details about this project, a bit background + line-by-line explanation, you might find this article on BIM Corner interesting: https://bimcorner.com/a-new-bim-file-format/

• Multicolor extension: https://github.com/paireks/dotbim-extensions-multicolor

• Wojciech Radaczyński

• Tom Van Diggelen
• Harry Collin
• Marios Messios