Uploading models to Pedestal 3D

Faculty administrators

• Steve Martin (Arts)
• Rita Hardiman (MDHS)
• Joe Barrins (ABP).

Preparing files for upload

File types

Pedestal 3D currently supports 3D models uploaded in either OBJ or GLB format. OBJ files are currently the most widely accepted 3D model file types across a variety of platforms and allow for files to be easily edited in the future. As such, OBJ is the recommended format for uploading to Pedestal 3D. Pedestal 3D will automatically generate GLB files from the uploaded OBJ format models.

For colour data to be displayed on the 3D model, 3D files require an accompanying image texture. Some forms of 3D modelling, such as photogrammetry, will produce image texture files; other forms, such as CT scanning, do not.

Models in OBJ file format require three files to upload with the colour data mapped to the 3D object:

1. OBJ file: This file contains the 3D model data, including the UV coordinates which determine how an image texture is mapped to the 3D model.
2. MTL (Material Template Library) file: Contains text that informs the hosting platform which image textures to apply to the 3D model.
3. Image texture: The image file that is mapped to the 3D object, containing the colour data. Image textures can be uploaded in either JPEG or PNG format.

Photogrammetry software packages (such as Agisoft Metashape) will generate these files for you when exporting the selected 3D object. 3D modelling software that requires users to import image textures (such as Blender) will require you to save your own copy of the texture. It is recommended to keep all associated files (OBJ, MTL, and your image texture) within an identifiable folder specifically for that object to prevent data from being lost.

File sizes

While Pedestal 3D can host large, high-detail 3D models, not all devices will be able to load large files without causing lag or potentially crashing. Pedestal 3D has the option to upload the same 3D model at multiple levels of detail to allow users to switch to the model most appropriate for their device. The ‘Medium’ detail model will load by default. The following 3D mesh and image size are recommended for each level of detail:

• Low: Up to 100,000 triangles and a 2048x2048 pixel texture.
• Medium: 100,000 to 500,000 triangles and a 4096x4096 pixel texture
• High: the full detail model and a 8192x8192 pixel texture
  • If higher resolution colour data is required, it is recommended to upload multiple 8192x8192 pixel images rather than an individually higher resolution image.

3D modelling software packages can be used to reduce the polygon/triangle count of a 3D object. If the 3D model was made using photogrammetry, the best option is to create multiple models within the photogrammetry software itself. If this is not possible, it is recommended to use MeshLab’s ‘Simplification: Quadric Edge Collapse Decimation (with texture)’ tool to create smaller version of the model. This method retains the existing UV maps so that the texture will still apply correctly, which is not the case using decimation tools in other software.

Scaling and position

3D models contain size/scaling data which allow users on Pedestal 3D to take measurements of uploaded objects. Before exporting 3D models, publishers should check to ensure that the scale of their models correspond to the actual size of the object they represent.

If models have been created but not scaled, and the publisher is unable to scale them, scaling can be manually adjusted using height or width information from the original object. Information such as this should be accessible in the university collection records.

3D models should be uploaded with their origin/pivot-point at the x, y, and z coordinates of 0, 0, 0. The object should be rotated such that objects are aligned along the x-, y- and z-axes. This will ensure that models can easily be manipulated in the Pedestal 3D viewport and Pedestal 3D’s cross-section tool functions intuitively. These settings can all be adjusted within most 3D modelling software.

Objects in Pedestal 3D are most easy to navigate when the z-axis, indicated by the blue line in the orthogonal view axes in the Transform module, is aligned towards the camera and the object is positioned at 0, 0, 0 in the move tool options. If you would like your model to be viewed from a different angle, use the rotate tool options to position it as you desire, before returning the move options to 0, 0, 0, then adjust the camera to your preferred position, and in the View module select ‘Set default position’.

Object management

Naming conventions

To preserve generated 3D models for future use and make them manageable by users other than the uploader, it is recommended to follow a comprehensible naming convention that allows future users to identify the 3D model by name. All files (ie the OBJ, MTL, and JPEG/PNG) associated with the 3D model should have the same name.

Users should be able to identify from the filename which faculty is associated with the object, what the object is, how this object can be identified in the university collections, which version of the 3D model we are working with, and what level of detail (high, medium, or low) this file is.

The following convention is recommended, with underscores connecting the elements and avoiding periods:

faculty_object-name_accession-number_version-number_level-of-detail

Example 1

An ancient Greek vase called a ‘lekythos’ has been scanned for teaching archaeology students in the Faculty of Arts. The scanned lekythos is registered in the Potter Collection under the accession number 1931.0003.000.000. After the original upload, some adjustments were made to the model to correct for scaling issues that were missed in the original upload. This model has been reduced in size to 20,000 triangles to allow users to view the model on low processing-power mobile phones.

Given this information, this model should be uploaded under the name:

Arts_Lekythos_1931-0003_v02_lp

• Arts indicates that the object is used by the Faculty of Arts
• Lekythos identifies what it is
• 1931-0003 lets us know which lekythos from the Potter Collection this model represents
• v02 indicates this is the second version uploaded
• lp indicates the model is ‘low poly’.

This way if the model is downloaded and used for research purposes, or one day the University transitions its models to a different hosting platform, the model will be able to be identified by someone other than its creator.

Example 2

A concrete core sample from the Heritage Building Materials Collection has been modelled for teaching in Architecture, Building and Planning. This sample is registered in the Heritage Building Materials Collection under accession number 2.116. This is the first model that was uploaded for this item, and it is the maximum detail version of that model. As such, it should be uploaded under the name:

ABP_Core-sample_2-116_v01_hp

• ABP indicates that the object is used by the Faculty of Architecture, Building, and Planning
• Core-sample tells us what the object is
• 2-116 tells us which core sample is represented
• v01 indicates it is the first version of the model
• hp indicates the model is high-poly, for maximum detail.

Divisions

Multiple instances of Pedestal 3D can be managed using Divisions, allowing for objects and users to be grouped together for different unit purposes. At the University of Melbourne, Division names are equivalent to faculty titles (eg Library, ABP). Divisions are created and managed by users with administrative rights.

Each Division will open into respective galleries, within which objects may be further organised into collections.

Collections

Specific 3D objects will be further categorised into collections. Collections may be used for a variety of purposes.

Some examples of how collections may be used are: an exhibition of a certain object type; objects related to a particular subject or course within the faculty; groups of certain materials that are helpful to be analysed together – looking specifically at crania within the MDHS division, for instance.

Metadata

3D Objects can be further identified by associating or ‘tagging’ metadata to the object. These are distinct identifiers that are manually entered during the uploading process and can be altered at any time. Users can use the search bar to find models associated with metadata terms.

When preparing models for upload, it is recommended to consider the kind of metadata you would like to have associated with the object, as this will influence the future discoverability of the model and the information that is available to people who are accessing it. The kind of metadata relevant to each object will differ based on the type of model, but the following groups of information should be considered:

Title

The name of the object, or a brief description.

Author

The copyright holder of the original item, not the 3D model. In the case of objects that are out of copyright, this will be the faculty in possession of the object.

User

The account uploading the model.

Division

The faculty or department for whom the object is relevant.

Copyright

The standard copyright guidelines for models in the University’s Pedestal 3D collections is to apply an ‘All Rights Reserved’ license to the model.

Copyright of 3D scans is associated with the original scanned object rather than the scan itself, which is considered a reproduction rather than a new creative work. If you wish to apply an alternative copyright license, such as a Public Domain dedication or a CC-BY license, you must respect the copyright of the original scanned object and take this into consideration before uploading the model under one of these other licenses.

Many objects that are scanned by or for the University of Melbourne are out of copyright or are by nature in the public domain. Creative works retain copyright for 70 years after the death of the author, after which they enter the public domain. Natural specimens do not contain copyright and are always in the public domain. These considerations may influence your decision to apply an alternative copyright licence. A CC-BY license may be appropriate if you wish for the university to be attributed as the steward of the original object and/or the creator of the digital model.

If uploading born-digital creative works or scans of creative works produced for the University of Melbourne, you should consult the terms under which the work was created to determine copyright and attribution requirements.

For a detailed description of the various copyright licenses available, consult the selecting a licence for your work guide or for further advice, contact the Copyright Office.

Description

A brief written description of the uploaded object.

Keywords can be included here, which will make the model more discoverable by the search bar.

Long description

A longer written description. This section can contain whatever information the publisher feels could be relevant to users viewing and analysing the 3D model. Web pages can be hyperlinked to connect the 3D model to other records of the original object.

Privacy control settings

Pedestal 3D allows for users to control availability settings of each model when uploading.

These settings include:

• Visibility of the object to the public
• Delegating through which division the object may be found
• Ability to download/or not

How to upload 3D objects

Once you have prepared your 3D model files, determined where in the Pedestal 3D divisions they should be uploaded, and prepared your accompanying metadata, the models can be uploaded by a Pedestal 3D account holder following these steps:

1. Log in. Click the Log In button on the top right hand corner of the Pedestal 3D front page and select Sign in with SSO to log in using your University credentials.
2. Select Create Item in the top right-hand corner of the page.
3. In the Info tab, enter the metadata that will accompany your object.
4. In the Files tab, use the Upload buttons to upload the OBJ, MTL, and image files
   • Low and High detail models can be added using the Add Low and Add High buttons, before these files are uploaded in the same way.
5. Set the availability, choosing between the following options:
   • Unpublished: Item is hidden from public view
   • Public: Item is publicly viewable
   • Unlisted: Item is viewable with link, file does not show up in library.
6. Edit the items:
   • Navigate to the item in the library, and select the Studio View button indicated by the green eye icon next to the blue pencil.
   • Make adjustments to the position of the model, the background settings, or whatever details you would like.
   • In the View module of the left-hand panel:
     • Set the default position - this is how the object will load for others when they access the model.
     • Set the thumbnail that will be displayed as this object’s listing using the ‘Update Thumbnail’ button.
7. Click Save changes, and you’re done! Your model is now accessible via the University of Melbourne Pedestal 3D platform and can be shared or embedded into Canvas pages.

Ensembles

As of the 3.0 release of Pedestal 3D, a new feature has been added known as ‘Ensembles’. Ensembles allow you to display multiple uploaded models in the same scene. Each model can be toggled on and off to view others in isolation, and adjustments can be made to the position, rotation, scale, and appearance of each model separately. This feature is useful for comparing groups of similar objects, connecting models composed of many separate elements, or for creative purposes such as curated groups of objects to convey a certain idea or emphasise a commonality.

Once each of the models you would like to group in an ensemble are uploaded to Pedestal, an ensemble can be created by following these steps:

1. Log in. Click the Log In button on the top right hand corner of the Pedestal 3D front page and select Sign in with SSO to log in using your University credentials.
2. Navigate to the Ensembles page by selecting Ensembles in the left-hand panel and select Create Ensemble.
3. In the Info tab, enter the metadata that will accompany your ensemble.
   1. If grouping models that are already publicly available, it is recommended to provide the key metadata of each model: the title, accession number, and key search terms.
4. In the Items tab, click add item and browse the models available. Models can be found using the search bar.
5. Set the availability, choosing between the following options:
   1. Unpublished: Item is hidden from public view.
   2. Public: Item is publicly viewable.
   3. Unlisted: Item is viewable with link, file does not show up in library.
6. .Edit the ensemble
   1. Find the newly created ensemble in the Ensembles page on the left-hand pane and select the green eye icon to enter studio view.
   2. Make adjustments to the position of each model, the background settings, or whatever details you would like.
   3. In the View module of the left-hand panel:
      1. Set the default position - this is how the ensemble will load for others when they access the page.
      2. Set the thumbnail that will be displayed as this ensemble’s listing using the Update Thumbnail button.