LiDAR & the iPhone 12 Pro – Part 2: 3D Object Scans software and publishing

TL/DR: Use SketchFab, MeshLab, and maybe Blender, be careful in SketchUp also don’t bother scanning individual objects smaller than a cereal box, and think carefully about scanning chairs…

This post is really quick, and is meant to discuss briefly the use of the iPhone to scan objects.  In this case I mean objects that are say domestic chairs to say a car or truck. It follows on from Part 1: Quick scanning tips, tricks, and software.

So, I have tried most of the apps that use the iPhone 12pro’s LiDAR sensor (amongst other techniques) and basically the bottom line here for most people don’t expect great detail for scanning of small objects.  Bookcases, sofas, cars, and Millennium Stones scan well, but smaller objects like chairs, cereal boxes are not ideal. 

Lots of effort is required to get anything good from scanning smaller objects with detail.  And that is 100% to be expected, Apple I think has really designed this as a way of occluding models within room-scale augmented environments so that object disappear through walls rather than sit uncomfortably beyond it.  Chairs come out a disappoint messy mesh, small boxes look wobbly.  My advice don’t bother or don’t expect too much!

Sharing your models/scans

I have had fun scanning cars and trucks and larger objects.  As well as small quarries.  But how can I prove some of this? Well for many people the next question is now what? How do I share with people who don’t have an Apple device (you can share your scans via the USDZ via iMessage but these should be for smaller in file size models).   Well, there’s not much choice!  For GIS professionals you could share it on the Esri platform called ArcGIS Online, but this is not ideal (not built for object navigation) and is expensive overkill for most people.  There is really only one other platform to share your models and many of the 3D scanning apps have an integration with it, that site is called SketchFab.  It is quite frankly brilliant with a huge feature set and a freemium pricing model for those dabbling.  Use this, you can annotate models and embed them in websites.  Honestly do not look elsewhere (no I am not getting paid for saying this).

Getting your model to your computer

Seems simple right?  Well from the iPhone you have some choices, you can email an exported model to yourself. Upload it to SketchFab (if the app has that option), save to ‘Files’ on your iPhone. For most models because I have dropbox I can do a ‘Share’ and ‘Save to Dropbox’.  For really large models sending them over wifi or mobile network can be slow.  If so install iTunes (I know, I know) connect your phone via the cable and basically go to the built-in file browser within iTunes to save your exported models to your PC.  This has the added benefit of you being able to save multiple models at once to your PC.

NB: The above process is referring to how you can do it in the free (and excellent) 3D Scanner App.  You have to click share, select the model file format and do save to files for transferring via cable.  It seems the act of clicking share and a file format actually makes the file.  Experiment like I have and you’ll figure it out!

Software

Depending on what you want to do with your scans, there are many choices out there. It always seems that the most capable software that happens to be free has the most hostile user interfaces.  But do not discount them for that!  For fixing things and doing more technical operations MeshLab is my go to software and supports most 3D formats (DAE and OBJ), and yes mesh can be used as a term for a 3D model although not always (in the file menu in MeshLab goto to ‘import mesh’ and select your scan).

If you want to just view your 3D models/scans then Windows 10 has a 3D Viewer that supports the major formats and is well worth having.

I also use SketchUp a lot (the pro version), yes you can bring scans into SketchUp, a word of warning though!  SketchUp does not like drawing lots of polygon triangles, to speed things up in a new sketchup file ensure draw edges and profiles is turned off for larger more complex models, this speeds things up.

For those wanting more from their 3D modelling software without paying, look at Blender it is fantastic and complex.  Learning this is well worth it, but it’s more for game/vfx/visualisation work than geospatial/architectural/planning.

In Part 3: Building Scans (inside and out) CAD and GIS I’ll be going into a bit more detail and discussion on my real interest in using the iPhone scanning capabilities.