OR MDL support - SDK released as open source

[linvanchene]

Update 2018 08 19

Nvidia released the Material Definition Language software development kit as open source:

https://blogs.nvidia.com/blog/2018/08/1 ... e-mdl-sdk/

https://developer.nvidia.com/mdl-sdk

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Original post:

OctaneRender 3 announcement, April 5, 2016

Native plugin ecosystem: OctaneRender will enable easy loading of plugins through ORBX modules that continuously update the host application with new features. New plugins will also enable support of different shader languages beyond OpenSL, including support for Nvidia’s Material Definition Language (MDL).

Source:

https://home.otoy.com/octanerender-3-an ... ap-update/

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Wed Dec 07, 2016 3:37 pm

We are exploring making it a module after OSL is done.

Source:

viewtopic.php?f=44&t=57905&hilit=MDL#p297617

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Statement at 22:25

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Fri Apr 28, 2017 2:35 am

Or we may add MDL shaders in Octane 3.1+ directly if Nvidia open sources the MDL compiler for it to truky become an open stadnard like OSL is today.

Source:
viewtopic.php?f=30&t=60989&p=314582&hilit=MDL#p312089

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From the outside it is very difficult to understand what exactly is happening behind the scenes.
As a customer I read the announcement that MDL would be supported and took this as a fact and assumed that this was going to happen in the year following the announcement.

I find it odd that now after more than a year has passed MDL is treated as an "option" only if Nvidia will make MDL open source.
Did Nvidia provide Otoy any assurance before the original announcement in 2016 that gave the impression that MDL is going to be open source?

1a) Did Nvidia change their mind after April 2016?
or
1b) Did Otoy change their mind after April 2016?

2) Why can Otoy not support MDL if it is not open source?


3) When will we know if Nvidia is going to agree making MDL open source?

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Side Note - Why does this matter to me:

I rely on using affordable licensed 3d content to create images in a reasonable time to quality relationship.
In 2013 I hoped that Otoy would partner up with DAZ3D with the goal that artists would start to produce licensed content with OctaneRender materials included.
Unfortunately in 2015 Iray and with it the Nvidia MDL was adapted as the official solution.
Afaik currently no one is providing licensed 3d content with OR materials on a large scale.
This means I currently am facing the following choice:

a) I render with Nvidia Iray but then can not use all the advanced production ready features of OctaneRender.
b) I invest large amounts of time to manually adjust basic auto conversion of MDL materials to the OR node system.

The best solution for me as a customer would be if Nvidia and Otoy could cooperate in a way that licensed content including MDL could be read directly without auto-conversion by OctaneRender.

I hope that both Nvidia and Otoy can find their place in a GPU render workflow.
It would be great if both companies could mutually support each other.
Otoy could support MDL.
Nvidia could support .ORBX

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[Goldorak]

1a) Did Nvidia change their mind after April 2016?
1b) Did Otoy change their mind after April 2016?

OTOY and NVIDIA both want MDL in Octane in 3.x and we're still going to try to do this ASAP.

But - we are also working to get Octane on AMD GPUs, mac AMD, etc. and if we add a dependency to the core engine that only works (well) on NVIDIA GPUs, we may be blocked from ever getting feature and speed parity on other devices and platforms . Not ideal...

2) Why can Otoy not support MDL if it is not open source?

NVIDIA told us they wanted to open source MDL and make it an industry standard just like OSL, which is why we felt good about supporting it after OSL was done. The issue is that without source code to a working shader compiler to see how MDL to bytecode is being generated, it's a black box - and not an open standard on par with EXR, OSL alembic and others that provide this src as well as spec (you want both). With OSL, the full compiler source is on gitbub, and it makes a huge difference in terms of how we brought it into Octane.

If we had full source to MDL compiler, we could, for example, have a shot at real time MDL -> OSL/OSO (by adding a new compiler target to NVIDIA's MDL compiler) , so we would not have to do anything special to support MDL materials in Octane 3.1+ on all platforms.


3) When will we know if NVIDIA is going to agree making MDL open source?

They say they are looking into it, but no date has been given. After we are done with OSL, and if this is still unchanged, we may look into an whether we can get MDL output cross compiled to OSL, even without the MDL compiler source. But it's really not ideal, and shouldn't be something we have to do if NVIDIA is going to follow through with making MDL open source.

[linvanchene]

Thank you for your detailed answers.
The additional possibilities with "open source" sound very exciting.
Let's hope for the best.
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[Goldorak]

Thank you for your detailed answers.
The additional possibilities with "open source" sound very exciting.
Let's hope for the best.
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We'll get there. I think it's what all parties want in the end.

[Leonides02]

I'm in the same boat as you, linvanchene. I'm a licensed customer who doesn't ever use Octane anymore because the conversion from MDL to Octane is simply too onerous. Any reduction in render times due to better production capabilities is annihilated with having to tweak / recreate shaders.

[linvanchene]

Blog entry from August 13, 2018 by Nvidia


"Security, customizability, flexibility and cost are a few of the benefits of open-source software for developers.
They’ll get all these and more from NVIDIA’s Material Definition Language software development kit, which is available starting today as open source."

source:

https://blogs.nvidia.com/blog/2018/08/1 ... e-mdl-sdk/

SDK download:

https://developer.nvidia.com/mdl-sdk

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Are the requirements now met so Otoy can support MDL in Octane?

[wader]

I'm wondering about the above references, as well.

Is the public MDL SDK not enough for Octane to use towards the purpose of converting MDL to/from OSL - either in real-time or offline?

[wader]

Somewhat related to the above . . .

If the below statement is accurate, then it seems OTOY actively makes our lives more difficult because the Universal Material Converter product could have potentially delivered script-based Iray <-> Octane material conversions for 3DS Max users, but stopped that work by request:

http://www.scriptspot.com/3ds-max/scrip ... -converter

Octane cancelled because OTOY did not want me to make it.

[Goldorak]

Somewhat related to the above . . .

If the below statement is accurate, then it seems OTOY actively makes our lives more difficult because the Universal Material Converter product could have potentially delivered script-based Iray <-> Octane material conversions for 3DS Max users, but stopped that work by request:

http://www.scriptspot.com/3ds-max/scrip ... -converter

Octane cancelled because OTOY did not want me to make it.

The above is news to me and I should know if it were accurate. Most likely a misunderstanding. About MDL, the SDK going open source was pushed for years by us, and I am glad NVIDIA finally did it. We will revisit MDL support after we have completed the major work on the new material layer and substrate changes coming in Octane 2019.x shortly, which will be the largest (and hopefully best and most artists friendly) change to Octane materials ever made, as it will basically replace the need for mixed materials. MDL shader support could be implemented along the lines of how we do OSL shaders now and in the future after the the 2019.x material system changes.

[wader]

Promising to hear @Goldorak , thanks for sharing your perspective.