MF.OV.MVR and MF.OV.GDTF

Brings support of MVR and GDTF files to Omniverse and USD. This repository contains two different extensions.

GDTF (General Device Type Format) defines an asset format that collects technical information about Audiovisual devices. It is currently centered on lighting fixtures and provide accurate digital twins of lighting devices from 100+ manufacturers.

MVR (My Virtual Rig) is a scene format that can describe an complete rig of lights, using GDTF assets at its core while adding capabilities to define groups, layers, DMX address and more to allow lighting designer to build virtual replicas of their lighting rigs and enforce a single file format from show design to previz to operation.

This repository contains two separate extensions :

• MVR extension
• GDTF extension

Requirements

• Requires Omniverse Kit >= 105
• Tested in USD Composer 2023.2.2 and 2023.2.0

Build

Build for Omniverse

• Just run build.bat
• Once the build is complete, the FileFormat dlls should be located under : _install/windows-x86_64/release

Build for USDView

The dependency configuration is contained in the usd-deps.packman.xml file To switch to the correct OpenUSD version for USDview compilation, it may be required to edit the packman configuration file to :

<project toolsVersion="5.6">
  <dependency name="nv-usd" linkPath="../_build/usd-deps/nv-usd/${config}">
    <package name="usd.py310.${platform}.usdview.${config}" version="0.23.05-tc.47+v23.05.b53573ea" />
  </dependency>
  <dependency name="python" linkPath="../_build/usd-deps/python">
    <package name="python" version="3.10.13+nv1-${platform}" />
  </dependency>
</project>

source setenvwindows

Test with usdview resources/scene.usda

Note : light meshes will not show up unless you have a GLTF FileFormat plugin enabled.

Alternate builds

At the bottom of this Readme, you will find alternative ways of building for Unreal 5.3 and Blender 4.0.

Using the extension

To enable the extensions in USD Composer:

• Window > Extensions
• Search for MF GDTF Converter or MF MVR Converter in commuunity and enable them with the "autoload" checkbox.
• Restart USD composer.

Sample files

MVR samples :

• 7-fixtures-samples.mvr
• fixture-line-gltf.mvr

GDTF sample

• Robin_MMX_Blade

Thousands of GDTF files are available on GDTF-share.

For example the very last version of the GDTF sample file we provide can be downloaded from here

Reference MVR/GDTF files

To reference an MVR or a GDTF file, just drag and drop the file on your viewport or your Stage Window.

Convert MVR/GDTF files

Note: to properly work with MVR files, both extension have to be enabled.

1. In the content tab, browse to the folder where you want to import your MVR or GDTF files.
2. Click the +Import button and select "External Assets (FBX, OBJ...)
3. Choose a MVR or GDTF file and wait for it to import.
   • MVR import
     • The import result will be stored in a folder with the same name as the imported file in the current content browser directory.
     • If GDTF files are referenced, they will be converted to USD in a subfolder.
   • GDTF import
     • The import result will be stored in a folder with the same name as the imported file in the current content browser directory.
4. To finalize the import, drag the freshly converted USD file in your project or open it.

Implementation notes

MVR.USD USD schema

Note : not every aspect of the MVR specification is currently implemented for USD, as we focused on the ability to retrieve the lighting fixture information.

1. Under the Root, you'll find Scope representing the different Layers of the MVR scene.
2. Inside them you'll find each GDTF Fixture represented by an Xform pointing to an USD payload.
3. Xform are named using their names and their uuid to ensure unique naming.
4. Xform also have custom properties (see Raw USD Properties) using the following convention: mf:mvr:property.

Root/
└─📁MVR-Layer1 (Scope)
|  ├─💠Make_Model_UID1 (Xform with payload)
|  └─💠Make_Model_UID2 (Xform with payload)
└──📁MVR-Layer1 (Scope)
   └─💠Make_Model_UID1 (Xform with payload)
   └─💠Make_Model_UID2 (Xform with payload)

MVR Raw USD Properties

When importing an MVR files, some properties specific to MVR and not compatible with USD will be imported as raw USD properties of an Xform holding a lighting fixture :

Example

GDTF.USD USD Schema

GDTF can have multiple structure type, but here is a typical example for a moving light.

Root/
└─💠 Base (Xform)
   ├─💠model (Xform)
   │  └─🧊 mesh (Mesh)
   ├─💠Yoke (Xform)
   │  ├─💠model (Xform)
   │  │  └─🧊 mesh (Mesh)
   |  └──💠Head (Xform)
   │      └─💠model (Xform)
   │         └─🧊 mesh (Mesh)
   └─📁Looks (Scope)

GDTF Raw USD Properties

Properties affecting the USD Prims properties

Fixture

Beam (Light)

XML Notes

Example of a fixture defined in a MVR file (contains some, but not all properties):

<Fixture name="Sharpy" uuid="C63B1F8D-6DAD-438C-9228-E33C6EF2947E">
    <Matrix>{-1.000000,0.000000,0.000000}{0.000000,-1.000000,-0.000000}{0.000000,0.000000,1.000000}{-766.333333,4572.000000,7620.000000}</Matrix>
    <GDTFSpec>Clay Paky@Sharpy [Bulb=MSD Platinum 5R 189W].gdtf</GDTFSpec>
    <GDTFMode>Vect</GDTFMode>
    <Addresses>
        <Address break="0">21</Address>
    </Addresses>
    <FixtureID>102</FixtureID>
    <UnitNumber>0</UnitNumber>
    <FixtureTypeId>0</FixtureTypeId>
    <CustomId>0</CustomId>
    <Color>0.312712,0.329008,100.000000</Color>
    <CastShadow>false</CastShadow>
    <Mappings/>
</Fixture>

Some notes on the properties:

• Matrix is in millimeters (applies to the last part, the translation).
• Color is in CIE 1931 color space and represent the color of a color gel or similar apparatus and not of the fixture itself.

Alternate builds

Build for Unreal 5.3

Unreal 5.3 uses USD 23.02 Use the following dependency

<dependency name="nv-usd" linkPath="../_build/usd-deps/nv-usd/${config}">
    <package name="usd.py310.${platform}.usdview.${config}" version="0.23.02-tc.1+pxr-23.02-build-patch.9ed269df" />
  </dependency>

• In your Unreal project, enable the USD Importer plugin
• Create a subfolder in your Unreal Project ex : MyProject/Content/USDPlugins
• Copy the plugInfo.json and the mvrFileFormat.dll at the root of this folder
• Adapt the plugInfo.json :
  • "LibraryPath": "mvrFileFormat.dll"
  • "ResourcePath": ".",
  • "Root": "."
• Add the MyProject/Content/USDPlugins in Edit > Project Settings > USDImporter > Additional Plugin Directories

Note.
Unreal is gonna complain about missing dll. Dirty fix is to add the following dll (take the one from packman) into the ...UE_5.3\Engine\Binaries\Win64

• boost_python310-vc142-mt-x64-1_78.dll
• python310.dll

Build for Blender 3.6.x or 4.0

Waiting for a cleaner way to provide build support for Blender, here is a step by step. Use the following dependency.

<dependency name="blender_usd" linkPath="../_build/usd-deps/nv-usd">
    <package name="blender_usd" version="63380-py310-usd23.05-windows-x86_64"/>
  </dependency>

In the repo.toml Modify the USD dependencies.

usd_lib_dependencies = [
    "ms"
]

Remove %{config} after usd_root

usd_root = "${root}/_build/usd-deps/nv-usd"

Copy the Plugin folder : omniverse-mvr-extension/_install/windows-x86_64/release/mvrFileFormat

into your Blender Plugin folder BLENDER_ROOT/blender.shared/usd

Resources

• Inspired by : NVIDIA's usd-plugin-sample
• MVR and GDTF homepage with Fixture Library
• Specifications Github repostory
• Gdtf.eu

Known limitation

• GDTF files using 3ds model are supported but will require python 3.10 cli installed on the host computer.
• Some MVR or GDTF files might fail to convert due to invalid or incomplete files.
• Only lighting devices are supported, prefer for importing mvr file not contaning trusses for instance. It could lead to strange behaviors and crashes.