3D Model Data Input Specifications

Wide-shot 3D rendering of buildings, houses, roads, and other urban structures

Table of Contents

Last Updated on May 7, 2024

Creating and converting your data into interactive visionary plans.

Data can get pretty complex. We try and keep it simple for you. After 20 years, we know a bit about it. We suggest you contact us for a quick chat. But below are some insights – as we know how busy you are.

This article is about environments and structures like integrated railways, roads, buildings, landscapes, bridges, culverts, OLEs, vegetation and elements.

Movable assets like machinery, plant, rolling stock (trains), characters and cars don’t need to be geo-referenced, but have their own data and discipline requirements, especially for rigging and behavioural simulations.

Simplified steps to making models

Creating

  • Capturing, creating and modelling 2D and 3D spatial data is a big job. Doing it well is important. We craft great 3D models, or digital twins, that perform perfectly in real time from almost any inputs – but the better the input, the more efficient and reliable the output.

Aligning

  • Geo-spatial coordinate systems are critical. Be sure data is in the same spatial reference system so it fits together. We provide services to translate between co-ordinate systems, but it’s better if your surveyors, GIS technicians and digital engineers do it.

Converting

  • Changing formats across myriad types, some of which are listed below, to move them into a graphics-accelerated interactive plan. Usually in an Unreal Engine 5 format. Once converted, the data can all be visualised and experienced in the same space.

Optimising

  • Real-time rendering requires discipline in geometry, materials and textures. A 200GB LAS point cloud file does not drag-and-drop into Unreal Engine, but a 2GB file might. Your low fidelity photomesh with 16k textures and 200 million triangles will need some work or reconsideration to be useful at human scale.

Integrating

  • This is often the toughest bit. Not just the data in the same space, but all connected, vertex by vertex, seamlessly integrated.

Geometric 3D line design and plan drawing of the interior of a commercial
This approach showcases the crafted 3D line design and architectural plan, revealing the interior layout of a dynamic commercial space. Geometric precision intertwines with creative vision, offering a glimpse into the fusion of form and function within the building’s structure.

Geo-spatial coordinate systems

All our models are geo-spatially referenced in the Mercator system in line with engineering standards. We can align the interactives to any co-ordinate system globally. To minimise data handling and costs, ensure your data is aligned to the same coordinate system and datum. Then, all other matters considered (ie quality and optimisation), all the data can overlay precisely.

In Australia, most infrastructure projects are planned and designed, and constructed, in the MGA (Map Grid of Australia) coordinate system. GDA 2020 conversions are moving slowly in the industry, and we can / convert from GDA 2020 as required.

Map projection of the world with latitude and longitude lines lines to represent the coordinate system
Our 3D models follow the Mercator system for geospatial referencing. In the Australian context, the Map Grid of Australia (MGA) takes centre stage in shaping infrastructure projects. Moreover, our transition to GDA 2020 enhances accuracy and reduces data-handling expenses.


Square tile texture map example with 1 x ID and 8k resolution for photogrammetry is the right way to provide texture information.

File structure to be provided in a regular tile format preferably.

Geo-position XML or txt file associated with data set.
Geo-position XML or txt file typical format provided with data set.

Photogrammetry / Photomesh

Geo-positioning

Exact grid and datum/projection used – Eg MGA 56 (GDA 94).

Geo-referencing: provided data should be supplied with metadata .txt or .xml file. The tiles should be close to origin (0,0,0).

Photogrammetry 3D data structure

Bentley reality capture (preferred).

Geometry resolution 2cm, 5cm and 12cm. Crispest geometry and clean edges preferred. No need to provide LoDs unless crazy big files – we will LoD it out.

Output texture resolution – <8k pixels per texture / map / atlas map. Preferable square textures please.

Keep it simple – 1 mesh/tile, 1 material, 1 texture.

Do not mix IDs or multi-subs (sub-materials).

File formats – FBX. OBJ. DWG. DGN.

Edited photogrammetry

Talented surveyors and photogrammetrists can extract and remove information, like trees and shrubs. This is great. But do not mix your IDs or multi-subs when doing so. Keep it to 1 mesh or tile, 1 material and 1 texture map for efficient results.

Survey TIN

Photogrammetry and photomesh

3D TIN geometry mesh – DWG < 1 million triangles per tile.

Survey Strings

3D spline feature survey – DGN, DWG, DXF.

Aerial photography

ECW (preferred) or Geo-TIFF, geo-JPG).

LiDAR / point clouds

ALS (Aerial laser survey), MLS (mobile laser survey) or TLS (terrestrial laser scan). To 2GB per tile LAS (uncompressed). Colourised point clouds preferred. Note LAZ is a compressed version of LAS.

Site photography

For visual reference: file types: JPG, TIF, TGA, DNG, CRR, CR2, RAW, PNG.

For use as production input – include GPS exif metadata with file types: RAW, CR2, CRR, DNG, PNG, TGA, TIF, JPG.

Grayish-white photogrammetric data of building structures on black backdrop
With photogrammetry and photo meshing, we deliver a 3D Triangular Irregular Network (TIN) geometry mesh with remarkable precision— each tile containing less than a million triangles – constructed from a blend of LiDAR survey and on-site survey data.

Survey mesh

A good example of a survey TIN mesh with about 1m triangle – built from LiDAR survey and site survey information.

Aggregated/Federated Design Models (BIM)

BIM design model

Includes all required references and assets eg textures maps, revit families, xrefs.

It is best to have the native input files, as aggregators / federators optimise data and diminish data quality.

File types: NWD, NWC, NWF, DGN, FBX, IFC.

Rail Design

3D design geometry

Includes corridor piers, structure, track, barriers, screens, OLE, etc

File types: FBX, DWG, DGN, OBJ, IFC.

3D design CAD

Includes design strings, centrelines, chainage

File types: DWG, DGN, GENIO, IFC.

2D design CAD

Includes cross-plans, sections, elevations, long-sections, SAPs – signal arrangement plans

File types: DWG, DGN, PDF.

Reports

Design drawing sets. Information on standards, offsets, rolling stock behaviour, safety zones, kinematic envelopes (DKE) etc.

File types: PDF.

3D data modelling specifications for planning

Road / Civil Design

3D design geometry

Include structures, piers, road surface, barriers, screens, furniture.

File types: FBX, DWG, DGN, OBJ, IFC.

3D design CAD

Include design strings, centrelines, chainage.

File types: DWG, DGN, GENIO.

2D design CAD

Includes plans, cross-sections, elevations, long-sections.

Plans to include details such as line-markings, kerbs, medians, etc.

File types: DWG, DGN, PDF.

Architectural Design

3D design geometry

Include references and assets eg textures maps, revit families, xrefs.

File types: RVT, FBX, SKP, MAX, IFC.

2D design

Include CAD plans, elevations, sections.

File types: DWG, DGN, PDF.

Design reports

Architectural and urban design reports and schedules of treatments.

File types: PDF, PPT, DOC etc.

Landscape and Urban Design

3D design

Geo-spatially referenced 3D design models in native formats.

File types: RVT, SKP, MAX, 3DM.

2D design

Includes layout linework, surface treatments, vegetation placement, size and vegetation species.

File types: DWG, DGN, PDF.

Design reference schedules

Includes urban design reports, landscape design reports showing schedule with high resolution images of treatments, material palettes.

Include detail on vegetation species.

File types: PDF, DOC.

data modelling

Media production inputs

Video editor inputs

Adobe AE packaged working files and Adobe Premiere Production working files or equivalent working files for any produced video content.

File types: AE, PP.

Native 3D model content generated to produce video output.

File types: MAX, FBX, IFC, MAYA (MA, MB), C4D, OBJ, PDF, AI, JPG.

Imagery editor inputs

Layered full resolution image file in native file formats to editing application (eg, Photoshop).

File types: PS, AI, PSB, INDD, EPS, SVG, PDF.

Native 3D model content generated to produce image output.

File types: MAX, FBX, MAYA (MA, MB), C4D, OBJ, RVT, IFC.

Video footage

Full resolution, as captured video footage, in native file format.

File types: ProRes, MOV, AVI, MP4.

Drone / chopper video footage

Full resolution, as captured video footage, in native file format.

Include flight logs with detailed camera and lens specifications for camera matching.

File types: ProRes, MOV, AVI, MP4.

Imagery editing inputs

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