# USDZ output for AR

Multiverse provides you of a complete and artist-friendly workflow to generate USDZ assets for Augmented Reality (AR) directly out of any supported version of Maya.

You can then use USDZ assets generated by Multiverse with Apple iOS 12, 13 and Apple macOS 10.14 “Mojave”, 10.15 “Catalina”.

Check out our “Maneki” asset it in action at https://multi-verse.io/ar

TIP

You can download the “Maneki” AR asset, and other assets, on our website (opens new window).

Visually speaking, you can go from this, to this:

Maneki in Maya


Maneki in iOS 3D


Maneki in iOS AR


Maneki in macOS Quick Look


Maneki in macOS Xcode (below in animation)

Watch Video (opens new window)

# What can be written to USDZ

USDZ is still rather new format and in evolutionary phase. Before reading the documentation on how to export assets to USDZ, you should be aware of the native USDZ limitations and characteristics:

“PBR” shading / look development You can use any number of materials in Maya.
The currently supported material is the StingrayPBS and it can be assigned directly to your geometry, or via the hardwareShader parameter that is present on any Maya materials (e.g. on aiStandardSurface).

> Note that StingrayPBS UV offset and UV scale must be left with the default settings.
No refractions
No indirect illumination, though iOS casts soft occlusion automatically and computes some environment illumination.
Geometry Avoid N-gons, loose vertices and non-manifold topology.
Bad topology is never good!
No volumes nor fog
No displacement
Texturing One set of PBR textures per material
Only one single UV set, with all UVs packed in within a [0,1] region, no overlapping UVs
No UDIMs
No per-face assignments
Animated transformations: from TRS Animated affine transformation via animated translations, rotations and scaling of your geometries and transforms.
Animated deformations: from binding of animated joints Animated deformations from binding of joints/skeletons with geometries.


> NOTE — Remember to freeze transformations for all objects before writing the asset.

# Generate USDZ files

In order to correctly generate USDZ file with shading and texturing you must use the “Stingray PBS” material for assignment. This has also the advantage of providing a correct preview for the look of your asset in the Maya Viewport.

Here’s a step by step tutorial:

  1. Launch Maya (2018, 2019, 2020 on all O/S is supported)

  2. Make sure Load the “ShaderFX” plug-in (this plug-in is part of Maya but is typically not loaded by default):

    Load the ShaderFX plugin which provides the StingrayPBS node

  3. Choose which 3D model/asset you want to use, in this case we are using the beautiful Maneki 3D model from J CUBE Inc (the model has a simple hierarchy and a total of 9K polygons):

  4. Assignment of materials — You can either:

    1. Direct assignment StingrayPBS → Shape — Assign one or more StingrayPBS materials to your geometries.
    2. Indirect assignment StingrayPBS → Any Material → Shape — You can do this through the hardwareShader parameter of any Maya materials, such as aiStandardSurface this will allow you to use one single shading network where you can both have your final lookdev shading network as well as you can pipe StingrayPBS to the .hardwareShader input connection of Maya materials (this attribute is usually hidden, and if not present it can be created: it will be recognized automagically by Maya).

    In both cases the supported for StingrayPBS textures are:

    - Color
    - Metallic
    - Roughness
    - Emission
    - Normal
    - Occlusion
    - Opacity (for transparency effect)
    
    1
    2
    3
    4
    5
    6
    7

    Maya Attribute Editor

    Maya Shading Network using the StingrayPBS material

    Special attention: About Opacity If your asset requires (semi-)transparent objects, in order to correctly you must make sure to set the Preset Material to Standard Transparent in the StingrayPBS property editor and then enable both Use Color Map and Use Opacity Map (because the default preset does not provide opacity support and settings from the material). Then, the opacity map must be used in Alpha channel of the Base Color texture. The material should now be able to pick it up and preview it in the viewport.

    NOTE — The opacity attribute will be ignored, always use the alpha channel on the base color texture instead.

Settings for enabling opacity support in StingrayPBS

  1. Preview the look in the Maya Viewport 2.0 before writing out to USDZ. This can be very helpful in iterating your work so, make sure you have enabled hardware texturing in the viewport:

  2. Write the asset to USDZ:

    1. Select the root node for the hierarchy of the asset in Maya outliner, then click on Multiverse USD (Asset) Write (the first icon on the left of the the Multiverse shelf)
    2. Write the asset with .usdz extension:

Output a static USDZ file… …or use the frame range to output an animation

Your USDZ file has been written to disk. You can read back your USDZ asset in Maya with a Multiverse read operation if you wish.

It’s time have fun and view it in 3D or AR and Let’s augment your reality!

View your asset in 3D or AR in iOS

If you have a iOS 12, 13 device, you can preview your asset in the following built-in iOS apps: Safari, Messages, Mail, News, Notes.

Supported AR iOS Apps

You can now natively Quick Look your USDZ files of virtual objects in 3D or AR by placing your 3D objects in the real world. You will see incredible detailed renderings, including reflections of real world surroundings in shiny virtual objects.

To insert an asset in your website, such as in in the http://j-cube.jp website here:

Simply write the following HTML markup for Previewing usdz in Safari:

<a href="JCUBE_Maneki.usdz" rel="ar" >
  <img src="maneki_stand.png" alt="Maneki AR">
</a>

NOTE — you can download the “Maneki” AR asset, and other assets here: https://j-cube.jp/solutions/multiverse/assets

Now browse on your website for your iPhone/Ipad and you will be able to click and see the asset in 3D Object and AR:

Maneki in iOS 3D Maneki in iOS AR

View your asset in 3D in macOS and Xcode

If you are on macOS 10.14 “Mojave” or 10.15 “Catalina” you may preview the saved asset in macOS directly using “Quick Look” or XCode:

Maneki in macOS Quick Look Maneki in macOS Xcode (below with animation)

https://www.dropbox.com/s/77qh89gk0uvv2n2/Nov-17-2018%2009-08-56.mp4?dl=0

Last Updated: 7/8/2020, 11:44:39 AM