Vray doesn't render procedural streamed meshes

[vandigital]

Vray isn't rendering any procedrual meshes.

Like if I stream bin files from realflow they wont render. Octane render picks them up as well as maxwell render.

Easy way to test is to create a procedural mesh in MODO.

[vladimir.nedev]

That's not entirely true. It depends on how the procedural mesh item was coded. If it provides all necessary interfaces, V-Ray for MODO will pick it up.
For example, the Gear and Rock procedural meshes work just fine.

Octane will work with procedural items that don't provide all interfaces only if you enable the Use Mode Render Cache option.

But the Render Cache still has bugs, so I prefer to use it only for items that cannot be exported in another way.

Beside the realflow bin files, what other procedural mesh items do you have in mind ?
I can add them to the list of item types exported using the MODO Render Cache API.

Greetings,
Vladimir Nedev

[vandigital]

Off the top of my head no.

Would be great if we could get support for the meshes that come from this plugin http://www.mootzoid.com/plugin/emreader

Pretty critical for VFX shots that have liquid since its one of the only ways to get the simulations into modo smoothly.

[vladimir.nedev]

Did you use emReader to load the .bin file ?
I was just testing with it since obtaining a Maxwell demo is a bit more complicated.

emReader should actually work without the render cache, it works with Octane even without the Use Mode Render Cache option.

This is either a bug in my code, or a bug in emReader that I can work around, considering Octane is able to load it.

Thanks for the pointer. I will let you know when I have progress on this.

Greetings,
Vladimir Nedev

[vandigital]

Thanks alot for looking into this!

Could you reply back here when its in a nightly build?

[vladimir.nedev]

Yes, I will reply here when the fixes are in the nightly builds.

I got it working, not sure whether the blame can be put on V-Ray for MODO or emReader.
The MODO SDK help doesn't provide a clear explanation of how the interface that V-Ray and emReader communicate with is to be implemented.
emReader implements it in a slightly different way compared to the MODO Gear and Rock items.

I need to fix a few more things before it is useful though.
Currently V-Ray won't detect animation on a procedural mesh.
Also changes to the procedural mesh channels won't be picked up RT.

Lastly, since you are going to use emReader with liquid sims, this probably means that the mesh has changing topology from frame to frame.
At the moment V-Ray for MODO will determine velocity by using the vertex positions at two consecutive frames, but this doesn't work when topology is changing.
So, I will need to provide an option (probably in the V-Ray Geometry Properties) where you can choose to use the provided velocity vectors.

Greetings,
Vladimir Nedev

[vandigital]

Yes will defiantly be animation heavy.

The velocity vectors are also needed for specific functions like motion blur, stretching and stuff like that.

[vandigital]

Any progress on this?

[vladimir.nedev]

Any progress on this?

I got it working in a single frame like I said before, and I am currently running the build to go in the nightlies ( 2016.07.20 ).

I ran into problems with animation though.
I modified my code and it works with both an animated Gear and Rock item (will not be in the 20th July nightly).
For example, animating the thickness of the Gear or some other channel. But, of course, this is pretty useless.

But the animation doesn't work with emReader or emPolygonizer5. It would work through the Render Cache API, but I don't have support for animation with it yet.
There must be something that emReader does incorrectly.
Basically you need a 3D viewport/MODO render window to force the mesh to be updated or emReader won't return it correctly.
It just returns the last mesh shown in a 3D viewport or requested through the Render Cache (which includes rendering with MODO).

Do you have contact information for the developer of emReader ?
I can't find it on his site.

Also, if you have the full version of Octane, can you check if Octane works with an animated emReader ?
I am interested to know if it works when Use Render Cache is not enabled.

Greetings,
Vladimir Nedev

[vandigital]

I got it working in a single frame like I said before, and I am currently running the build to go in the nightlies ( 2016.07.20 ).

I ran into problems with animation though.
I modified my code and it works with both an animated Gear and Rock item (will not be in the 20th July nightly).
For example, animating the thickness of the Gear or some other channel. But, of course, this is pretty useless.

But the animation doesn't work with emReader or emPolygonizer5. It would work through the Render Cache API, but I don't have support for animation with it yet.
There must be something that emReader does incorrectly.
Basically you need a 3D viewport/MODO render window to force the mesh to be updated or emReader won't return it correctly.
It just returns the last mesh shown in a 3D viewport or requested through the Render Cache (which includes rendering with MODO).

Do you have contact information for the developer of emReader ?
I can't find it on his site.

Also, if you have the full version of Octane, can you check if Octane works with an animated emReader ?
I am interested to know if it works when Use Render Cache is not enabled.

Greetings,
Vladimir Nedev

Yes I will point him to this thread.

Octane does work with animated emReader. However I think you have to reload each frame, which it does automatically. Ill test it out again and let you know!

[mootzoid]

Hi guys,

I am the developer of emReader and emPolygonizer5.
Today I installed the demo version of VRay for Modo and was able to reproduce the rendering issues.
I tried to find and fix the problem, but unfortunately without success.

@vladimir.nedev : could you get in touch with me directly? You can find my email address on my web site www.mootzoid.com: just scroll down and on the bottom right you will see a little letter icon. Then we can try and figure out what the issue might be.

Thanks!
Eric Mootz

[vladimir.nedev]

Hi guys,

I am the developer of emReader and emPolygonizer5.
Today I installed the demo version of VRay for Modo and was able to reproduce the rendering issues.
I tried to find and fix the problem, but unfortunately without success.

@vladimir.nedev : could you get in touch with me directly? You can find my email address on my web site www.mootzoid.com: just scroll down and on the bottom right you will see a little letter icon. Then we can try and figure out what the issue might be.

Thanks!
Eric Mootz

Thank you for looking into this, I sent you an e-mail.

Greetings,
Vladimir Nedev

[vandigital]

Thanks guys for looking into this.

On a second note would exporting as .abc from realflow mean I can import using vray proxy and render that way?

[vladimir.nedev]

Thanks guys for looking into this.

On a second note would exporting as .abc from realflow mean I can import using vray proxy and render that way?

Yes, you can try this and see how it goes, it should work.
We also support vertex colors from Alembic files. You can access them by using MODO's Weight Map Texture.

Greetings,
Vladimir Nedev

[vandigital]

Yes, you can try this and see how it goes, it should work.
We also support vertex colors from Alembic files. You can access them by using MODO's Weight Map Texture.

Greetings,
Vladimir Nedev

Ya I will try it out and let you know if motion blur and all that renders. I suspect it will this is how it works in maya/vray.