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Unnaceptable Revit Workflows - Light and Materials

PostPosted: Mon May 07, 2018 4:15 pm
by SamuelAB
Last year, when I tried the Revit plugin, there were two major limitations that made the plugin useless.

Lights were not created automatically, users had to create a whole new geometry to host the IES file instead of using then build in Revit light geometry.

Materials that were not default Revit materials had to be processed manually.

These additions to the workflow make the plugin a nuisance instead of a useful tool. Have these problems been fixed yet or will they be fixed within any foreseeable timeline?

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All other Revit rendering plugins do not require additional work to render from Revit, you just press Render and it knows that materials and lights in the models. This is quite unfortunate since Octane is otherwise the best tool for the job. I would love to tell people to get rid on Vray, but this additional work makes that impossible. I cannot wait to use Octane to render my Revit buildings!

Re: Unnaceptable Revit Workflows - Light and Materials

PostPosted: Thu May 10, 2018 1:11 am
by face_off
Lights were not created automatically, users had to create a whole new geometry to host the IES file instead of using then build in Revit light geometry.
Octane requires geometry to emit light from, so some Revit lights will work, and others require the addition of polygons as emitters.

Materials that were not default Revit materials had to be processed manually.
The Revit 2018.1 and 2019 releases of the plugin locate custom textures used in Revit materials, so this issue should now be addressed (assuming I understand your concern correctly).

Paul

Re: Unnaceptable Revit Workflows - Light and Materials

PostPosted: Mon May 14, 2018 7:23 pm
by SamuelAB
Hi Paul,

Adding geometry to lights is not a workable solution. Every other render engine uses the built in light emitting surfaces (special internal geometry). Placing additional geometry in lights would obstruct the light and change the lighting result on top of creating an extra work step.

Why is Enscape, Vray, Corona and Revit able to do all this without us creating extra geometry? It seems like Octane is missing something fundamental about the lights.

Re: Unnaceptable Revit Workflows - Light and Materials

PostPosted: Tue May 15, 2018 12:46 pm
by SamuelAB
If anything, Octane needs to copy and paste the existing light meshes in Revit. You can export the file as an FBX if you cannot find these meshes.

The burden should not be on the user, especially if it will be ruining their model for anything else than Octane rendering.

Re: Unnaceptable Revit Workflows - Light and Materials

PostPosted: Tue May 15, 2018 1:23 pm
by face_off
I am not sure what you mean by "special internal geometry". Revit provides all scene geometry to Octane, so if it has an emitter surface (like a light fitting), this will be present in the Octane scene, and you can change that geometry's material to an emitter (if it was not already done automatically by the plugin). Octane is a physically accurate rendering, so it needs geometry to emit light from. There is no concept of a point light, or directional light in Octane (since these light produce light from nothing, which is not possible in the real world).

Paul

Re: Unnaceptable Revit Workflows - Light and Materials

PostPosted: Wed May 16, 2018 2:12 pm
by SamuelAB
Revit uses a 'Light Source definition'

This source can be:
Point (just create a small sphere to imitate this, but I agree that no source is infinitely small)
Line (Just create a thin rectangle)
Rectangular (nothing to change here)
Sphere (nothing to change here)

The contribution can be:
Spherical (meh, unreal)
Hemispherical (meh, unreal)
Spot (Meh, unreal)
Photometric Web - This is using an IES file, this is the only 'real' distribution. Anything else is seen as invalid in photogrammetry software like Elumtools.

Any emitting material in unrealistic for photogrammetry since it cannot be associated with an IES files (except in Octane).

So using the proper geometric pieces, you can create your own geometry. If I create a Octane sphere to emit light, it will block my sphere that already emits lights for every other rendering software out there! so all of a sudden, iray, Corona, Vray, Arnold, Revit, Elumtools and Enscape will stop working!

When you export a Revit FBX to 3ds Max, it already comes in with all the lights. Points become small square or circles and lines become thin rectangles. Actually what I do when working in 3ds Max is use the Vray converter to convert my lights to Octane (Octane does not provide this functionality, but the Vray converter works for it).

I now work in a large firm of 200+ people and I would love nothing more than to recommend Octane in Revit!! I just need the light to work for it to make sense. It seems like we were already able to fix the materials thanks to the 2018 material SDK. Just need one more thing!

Re: Unnaceptable Revit Workflows - Light and Materials

PostPosted: Wed May 16, 2018 2:14 pm
by SamuelAB
Forgot to attach this image

Light.jpg

Re: Unnaceptable Revit Workflows - Light and Materials

PostPosted: Thu May 17, 2018 12:18 am
by face_off
If I create a Octane sphere to emit light, it will block my sphere that already emits lights for every other rendering software out there!
Can you send me a scene where other renderers are picking up the emitter geometry but Octane is not pls?

Thanks

Paul

Re: Unnaceptable Revit Workflows - Light and Materials

PostPosted: Fri May 18, 2018 5:46 pm
by SamuelAB
Here you go!

I've placed an image showing you how to expose the light source IES web.

There is also the original IES files in there, sorry it is a bit of a mess. Has some zipping problems.

There is only one RVT file in there. Thanks for looking into this!

Re: Unnaceptable Revit Workflows - Light and Materials

PostPosted: Wed May 30, 2018 3:31 pm
by SamuelAB
Hi Paul,

Any luck or update on this?

Also, I don't seem to get notifications from the forum where there is an answer, so sometimes I forget to check back in.