# 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:
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. |
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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:
Launch Maya (2018, 2019, 2020 on all O/S is supported)
Make sure Load the “ShaderFX” plug-in (this plug-in is part of Maya but is typically not loaded by default):
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):
Assignment of materials — You can either:
- Direct assignment
StingrayPBS → Shape
— Assign one or moreStingrayPBS
materials to your geometries. - Indirect assignment
StingrayPBS → Any Material → Shape
— You can do this through thehardwareShader
parameter of any Maya materials, such asaiStandardSurface
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 pipeStingrayPBS
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)
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7Special 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.
- Direct assignment
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:
Write the asset to USDZ:
- 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)
- Write the asset with
.usdz
extension:
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.
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:
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:
https://www.dropbox.com/s/77qh89gk0uvv2n2/Nov-17-2018%2009-08-56.mp4?dl=0