Few Bug to report and talking

Omniverse Apps
1

Bug Report：
On Maya 2020, Some of the mesh from USD file will be convert as a empty maya group.
On Maya 2020, If you made some model and import a lookdev USD file, the Lookdev USD file will not be a refrence file.
it will increase usd file size. and not easy to manage and change.
On Create, when adjust scene unit nothing happen, this is a problem between Maya with Houdini scene.
In Houdini, scene size will be cm not m.
On Create, import refrence usd from top manu sometime empty, but on brower, you can drag in to stage.
On Create, Exposure not currect, I must manully adjust those value.
On MDL, theres not ocio, for safty work, you guys should telling every user when making texture, the color space should use srgb, cause If some texture are linaer, when Usd fill the texture on mdl shader, and use create for render.
the color space change from linaer to srgb and convert to aces for viewport.

Personal confusion:

How to render muilt usd file and genarate thumbnails,
for our studio, every asset before package as usd, we always refrence our Lookdev file to Render a mp4 to upload ftrack manage.

when we can use VDB sequence?

and for years ago, alpha test time, I am cerrently use Substance Designer for making MDL shader, but now, when i move on Create and modify MDL Shader, I am so comfuse about those name, wtf for those overlay name, even I try to find a float type node i need drag every overlay node to find whick one is float1 or float3.
and i feel sad about i spend over half years look mdl handbook pdf and test many shader, and try to remenber every single bsdf vdf etc…
now it disappear for Create.
for artist , MDL absolutely unartist, 90% artist cant handle those thing.
for tech art, it didnt have enough document for learn how to build cunton shader.

For omniverse, most material in those app using MDL and USD.
No matter what type of work for USD, even somebody not a tech art, they can learn USD from pixar web or most dcc like Houdini and maya.
but for MDL , its so hard to learn, MDL cant systemly learn all the knowlage for product now.
over 3 month, most people ask me how to build a shader like someting.
the only anser i can say is “try to read those pdf”

here is my test lookdev:
https://drive.google.com/file/d/1d5PiXpGzRVqXhHNmkpJ237U5z_f-n7fZ/view?usp=sharing

Hopfully Omniverse better
Cheers
Jiucao

2

Hi @Jiucao! Thanks for reaching out! I am working on getting answers to all of your bug reports and questions. I appreciate your patience.

3

On Maya2020, When livesync On, if switch HDR texture from skies broswer, Maya will crash,same as asset.

4

(Link to our documentation: https://docs.omniverse.nvidia.com/)

Bugs

I need some general information about your system environment for each of your bugs

  • Operating System
  • GPU
  • GPU Driver
  • Application & Version

Maya 2020 Questions & Bugs

(Link to our Documentation: Maya Connectors — Omniverse Connect documentation)

  • “Some of the mesh from USD file will be convert as a empty maya group.”

    • Can you explain the steps you use when converting a mesh from USD?
    • Can you please zip and send me a link to your log files when this happens? C:\Users\ [YOUR NAME] \ .nvidia-omniverse\logs
    • Also send me any console errors that appear

  • “If you made some model and import a lookdev USD file, the Lookdev USD file will not be a refrence file. it will increase usd file size. and not easy to manage and change.”

    • Notified Developer to help answer this question

Create Questions & Bugs

(Link to our documentation: Create Overview — Omniverse Create documentation)

  • “when adjust scene unit nothing happen, this is a problem between Maya with Houdini scene”

    • Can you explain the steps you use to adjust the scene?
    • Can you please zip and send me a link to your log files when this happens? C:\Users\ [YOUR NAME] \ .nvidia-omniverse\logs
    • Also send me any console errors that appear

  • “import refrence usd from top manu sometime empty, but on brower, you can drag in to stage.”

    • Can you send me a screenshot or video of this happening?

  • “Exposure not currect, I must manully adjust those value.”

    • Can you explain the process you use or send me a screenshot for an example?

  • “When livesync On, if switch HDR texture from skies broswer, Maya will crash,same as asset.”

    • Can you explain the steps you used to create this crash?
    • Can you please zip and send me a link to your log files when this happens? C:\Users\ [YOUR NAME] \ .nvidia-omniverse\logs
    • Also send me any console errors that appear

Houdini Questions & Bugs

(Link to our documentation: Houdini — Omniverse Connect documentation)

  • “scene size will be cm not m.”
    • Are your scenes importing from Houdini with the wrong measurement reference?

MDL Questions & Bugs

(Link to our documentation: Omniverse MDL Materials — Omniverse Materials and Rendering documentation & NVIDIA Material Definition Language)

  • “theres not ocio, for safty work, you guys should telling every user when making texture, the color space should use srgb, cause If some texture are linaer, when Usd fill the texture on mdl shader, and use create for render. the color space change from linaer to srgb and convert to aces for viewport”

    • Notified Developer to help answer this question

  • Need better documentation on MDLs

    • I will notify our documentation team about this request

  • “how to build cunton shader”

    • Notified Developer to help answer this question

Questions

  • “How to render muilt usd file”

  • How to “genarate thumbnails”

    • Thumbnail Generation is off by default. You can enable it here: Preferences > Thumbnail Generation > Save USD Thumbnail on Save.

  • “for our studio, every asset before package as usd, we always refrence our Lookdev file to Render a mp4 to upload ftrack manage.”

    • Did you have a question here? I want to make sure that we answer all of your questions!

  • “when we can use VDB sequence?”

    • For the moment, VDB support is limited to the Flow NanoVDB emitter. This support primarily allows VDB to influence the Flow simulation, but can also be used in a limited capacity for visualizing the volume.
    • Broader and more generic support is in progress
    • You can view our Public Roadmap here: Trello

  • “I am cerrently use Substance Designer for making MDL shader, but now, when i move on Create and modify MDL Shader, I am so comfuse about those name, wtf for those overlay name, even I try to find a float type node i need drag every overlay node to find whick one is float1 or float3.”

    • I have notified the developer to help answer this question
5

Hello @Jiucao! Here are some answers for you from the Development team.

“If you made some model and import a lookdev USD file, the Lookdev USD file will not be a refrence file. it will increase usd file size. and not easy to manage and change.”

  • We don’t currently support import as a reference. we merge the usd file.
  • We can consider this in a future release.

“scene size will be cm not m.”

  • Houdini units are in cm to match Create’s units.
  • We can consider adding unit conversion tools to help with unit conversion ( (e.g., scale the scene and update the stage meters per unit value, etc.)

About your MDL feedback, it seems to be about the MDL node set that comes with the graph editor.

  • This can be solved with the graph editor where float and float3 conversions, and applicable nodes, are easier to find and use than by reading the MDL specification document.
6

Sorry for delay.
I am using Windows10, Ryzen 3950X , X570 motherbord, 128G Ram, RTX3090 *2, The Driver version is 471.11 studio, Houdini 18.5.499,Maya 2020.4

For Maya Part, When i Using Houdini Build a USD file but None Pack any polygon, i guessMaya connect plugin seem to define polygon to Group.

For unit, i mean, when i change setting inside Create, it wont automaticly change scene unit or tell me restart project for resize scene, that is what i confuing…

cause someting create unit not easy to manage, for example, when we create a dome light then open that usd from maya or houdini, we need manully change that value, then what ever i did someting for this usd file, i need carefully those value i has changed, otherwise, teammate will get some trouble.
so i seggest every conncect plugin build a preset or make a list tell people what value we qerrid should be convert unit.

for exposure part. the question is, measure exposure cerrect or not by using eye are stupid. so that is the reason we are using ocio for make sure everybody render are cerrect, for most render engine they have a feature when you move mouse you can get the exposure value.
because every project or everybodys computer are diffrent, i think build a measure tool better then measure by eyes.

for livesync crash, i guess it the reason is when you click skies broswer HDR, it base on weblink, when livesync on, conncect plugin will direclly send the file string on maya, but real process is when we click broswer asset, it will download frist,then create will load it,but for connect it didnt make a buffer for download process.

For MDL, when i telk about MDL, i am tring be a artist not a tech art or enginer, i belive mdl for anybody who have coding backround are not hard.
but for artist, i mean, for most graphs guy, building a mdl shader is hard.
i will say at that moment, every single nvidia mdl shader are amazing, but for artist, it didnt have a smooth leaning curve, it didnt have enough information and transparency to know how to build a shader like you guys build,
that a big problem for user, cause create cerrently just using mdl and usd , right?

for muilt render, sorry about my word, its not clearly to help developer understand what that meam.
I mean, i wanna know how to using python api to calling kit or create render 100 or 1000 file without open file and render one by one.

I have already gave you guy my test file as google drive link.