[iPhone12Pro/iPad] 3D scanning with the LiDAR app “Polycam”

With the introduction of the LiDAR feature to the iPhone 12Pro and iPadPro, 3D scanning has become more accessible than ever before.

There are a number of 3D scanning apps out there, and it’s hard to know which one to use.
In this article, I will introduce you to one of these apps, Polycam, and show you how to use it.

*Environment used in this article
Model used: iPhone 12 Pro
Version: iOS14.6

What is LiDAR?

LiDAR is an acronym for “Light Detection And Ranging”.
LiDAR is based on the time it takes for a laser beam to reflect and return to the object when it is photographed, and can be used to obtain information on the depth of the subject space and the 3D shape of the object.

Difference between 3D scanning and photogrammetry

Both methods can be used to create CG models, but is there a difference?
Here is a simple comparison between LiDAR and photogrammetry.

  3D scanning (LiDAR) Photogrammetry
What you need iPhone/iPad + app Camera (normal one is OK) + PC + editing software
How to collect Date Light source Multiple photos
How to take photos As if you were recording a slow movie While paying attention to the overlap.

Detailed comparisons have been covered in past article, so please refer to it for more information.

Polycam, a 3D scanning app for iPhone/iPad

Polycam Preview

Polycam Preview

Polycam can be used on both iPhone and iPad, but please be aware of the following two points

  • Only iPad Pro 12.9″ (4th generation), iPad Pro 11″ (2nd generation), iPhone 12 Pro and iPhone 12 Pro Max models with LiDAR sensor
  • iOS14 or higher recommended

The app is basically free to download, but you can pay to increase the number of extensions you can save and improve usability.

Polycam Pro Yearly 4,400 yen/year
Polycam Pro Monthly  880 yen/month
Polycam Pro 14,000 yen / full purchase

The following formats can be saved.
If you save in OBJ or GLTF format, you can also upload to STYLY or Unity.

Mesh data .obj, .glb, .usdz, .dae, .stl, upload directly to Sketchfab
Point cloud data Export as .dxf, .ply, .las, .xyz, and .pts
Floor plan data .dae

Let’s try to use Polycam

Download it from the AppStore.

Search for Polycam

Search for Polycam

When you open the app after the download is complete, you will see this screen.
If you create a new account, you will be able to share your scanned models on the web and access them from other devices.

Welcome to Polycam!

Welcome to Polycam!

captures

The list of models you have scanned will be displayed.

captures

captures

albums

You can create an album from +create new album.
This is useful when you want to organize your scanned models.

albums

albums

When you create an album for the first time, a screen like this will be displayed.

create your first album

create your first album

Enter a name for the new album and a description of the album (optional), and then tap create.

create new album

create new album

explore

You can view the list of models shared by other users.
Click on the earth symbol in the upper left corner to see models shared near you on a map, and you may discover a new aspect of a familiar place.

explore

explore

3D scanning with Polycam

Now let’s try a 3D scan.

Tap the + symbol

Tap the + symbol

Tap the + symbol in the upper right corner of the app screen to launch the camera.
When you’re ready to take a picture, tap the round button.
Then, slowly move the camera while pointing it at the object you want to scan.

Scan so that the blue area is gone.

Scan so that the blue area is gone.

When you are done, tap the red square button again to finish, and the scanned model will be displayed.
If the scan area is large, it will take a little longer.

The place where you have moved is shown as a green square.

The place where you have moved is shown as a green square.

Tap PROOCESS to process the model and reflect the texture.
The “est: 19seconds” beside it is the approximate time it will take to process, which in this case is 19 seconds.
Change the settings according to your shooting purpose.

FAST Processing speed priority
SPACE Space
OBJECT Object
CUSTOM See the table below

If you specify CUSTOM, you can change the settings during processing by yourself.

CUSTOM setting contents

CUSTOM setting contents

DEPTH RANGE Sets the depth range to be used when processing each frame of the capture sequence.
This is useful for excluding background material when capturing an object.
VOXEL SIZE The minimum voxel size to use when processing this capture.
Smaller voxel sizes take longer to process and require more polygons.
SIMPLIFICATION he level of simplification to be applied to the mesh before texturing.
For example, a value of 40% will reduce the polygon count by 40% before texturing.
The higher the value, the lower the polygon count.
Tap PROCESS and wait a moment for the process to finish.
Processing in progress

Processing in progress

When processing is complete, the model will appear like this, and you can swipe or pinch out to see the completed model from various angles.

The scanned 3D model

The scanned 3D model

Tapping the ① icon will display the model’s shooting information.
From here, you can enter the model’s name or add it to an album.

Model's photo information

Model’s photo information

Tap the ② icon to share the model’s photo to the Polycam explore.

You can also display the model on the map and set it to public or private.

You can also display the model on the map and set it to public or private.

You can also edit the model from the menu below.

PROCESS Process the model again。
CROP Crop the model with a cube-shaped object to remove unnecessary parts.
MEASURE Displays the distance between two specified points in the scanned model.
EXTEND Add another 3D scan of the model.
VIDEO Create and save a video of your scanned model.

Share and upload

Tap the ③ icon to share to SNS or export to CG or other software.
If you have not paid for the software, there is a limit to the extensions you can export.

Share

Share


Export

Export

When you use the model in STYLY, there are following two ways to do that.

  • Share on Sketchfab
  • Select OBJ or GLTF and export to PC

In this article, I will show you how to upload an OBJ model to STYLY.

After selecting the file extension, share it to your computer via AirDrop or Mail.

Tap OBJ.

Tap OBJ.

Select the share method.

Select the export method

Select the export method

The file will be shared to your computer in ZIP format, but you can use it as is without extracting it.

3D scanned model data

3D scanned model data

How to upload to STYLY

Let’s try to upload your 3D model to STYLY.

Create a STYLY account

How to create an account

How to upload to STYLY

How to upload from Unity to STYLY

Tips for a clean 3D scan

If you scan without following the tips, the 3D model will not be generated properly.
So please pay attention to the following points when scanning.

Scan slowly

If you move too fast, the model and texture will not be scanned correctly.
Scan while checking on the screen that the polygons have been loaded properly.

Be careful where you move.

When scanning a building or space, try to move in a single stroke, not back and forth in the same place.
This will overwrite the model you have already scanned and may cause the polygons to shift or disappear.

Scan from different directions

It is advisable to scan the 3D model from as many 360 degrees as possible so that there is thickness to each of the X, Y, and Z axes.
If the model cannot be scanned, the polygons will not be reflected properly because the model information cannot be obtained, and the texture will be stretched.

Example of scanning a low table in my room

Example of scanning a low table in my room

You will get used to it by repeating the process several times, so have fun with it!