IRay, UE4 and DAZ Tech Discussion
Joe.Cotter
Posts: 3,362
Hi all, I wanted to have a central place for discussing some of the current and forthcoming IRay, UE4 (and DAZ related) tech in hopefully an easy to digest manner.
There are a number of discussions going on here about IRay, but I would like to focus on the underlying technology and expand that into educated perspectives on the future directions of this technology. With that in mind, I'd like to kick it off with a couple quick links...
As people add links, I may copy their links to these first couple of posts so that people don't have to root through the whole discussion for links that are particularly popular or pertinent.
Due to the nature of updating this front page with new links as they become available, anyone interested in this topic will want to check in on the front page from time to time for updated information.
Nvidia Physics Hair: Thanks to Luv Lee for pointing this one out. While I've been watching IRay demos for a while now, this one slipped past me and was the inspiration for the thread.
Nvidia (Official) Physics Flex video
NVIDIA PhysX FleX v0.25 【Tech Demo】 i7 4770K GTX 780Ti 【1080p 60 Fps】Another Flex video that showcases some of the great features of Flex
NVIDIA Iray: Light Path Expressions and Compositing Elements Light Paths and compositing are very powerful tools that aren't currenlty exposed in the DAZ environment but are common tools in most advanced environments, including Blender, VRay and many other render environments. This technology was brought out in a product by Dreamlight for the 3DL environment (don't remember the name atm..) Hopefully we will see this technology in a near future update to DS. Forum link to discussion on LPE in IRay.
London Loft in UE4. While most of us have probably seen some of the many Realtime Archtectural demos in UE4, this is a nice quick example that is included to open the discussion related to this type of use of the technology and perhaps where DAZ might fit into that environment.
Nvidia's IRay Home Page Some good information here
IRay Origins For the curious.
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Comments
Some cool effects:
3ds max Car peeling effect - Nvidia Iray
(Also a placeholder for other cool effects as we discover them.)
Techniques:
Dreamlight has a quick video that covers basic lighting in IRay, which is a good starting point.
Sickleyield has some videos on her channel which expand on the basics.
Tutorial Subsurface Scattering - 3DsMax & IRAY I know this is 3DS Max, but sometimes we need to look to other environments to expand our techniques in our preferred environment. I thought this would be a good example of when this might be helpfull.
Forum link: Creating IRay Shaders
Vincent Brisebois has a couple of interesting videos on Youtube worth checking out. One is a lighting tutorial and another is a Shader Mixer tutorial.
Unreal Engine supposedly imports IRay/Mental Ray shaders but I haven't found a good link on this yet. If you have found a good link demonstrating this, please share. :)
DAZ Specfic IRay Links:
Popular Videos - DAZ Studio & Iray Youtube #DAZStudio playlist.
Other Sites and Resources:
IRay is independent of the platform that feeds it for the most part, so shaders, light resources, HDRI sources, etc... should be pretty much universal, whether from Autodesk, DAZ, or other sources to some extent if we go back to the source (mdl etc...) It would be interesting to see what we can come up with for importing/exporting resources from various environments, both techniques and resources.
HDRI:
Forum Link: The importance of true HDR in HDR images
Free Red Cliffs HDRI map. "This is a 32 bit HDR 16K image shot in California with a Canon 70D.The full range of light in this scene is contained in the HDR image and will be strong enough to illuminate your 3D scene and cast shadows. Zip file also contains 10 5K jpg backplates"
Environment Comparisons:
While we might all have our favorites, or be limited in what we have available, it is good to be aware of the range of envoronments out there, their strengths and weaknesses. I believe well rounded understanding is usually of benefit.
iRay vs Octane vs Corona
Iray & complex Scene
Comparing Global Illumination (GI) Renderers, Blender.org and The associated PDF. Dispite the title, this is not just about Blender. It centers on Radiance, which evidently is the parent of many of the features of modern render engines such as HDRI as a light source and sun/sky features with latitude/longitude/time of day. Some features of Radiance have not been implemented in most environments yet, such as rayfiles. Rayfiles are a light source definition like IES but they contain more information for the render engine and as a result are both faster and more accurate. Some implementations of Radiance include Autodesk360, Autodesk's cloud rendering service, and a Luxrender implementation. The primary users of radiance aka rayfiles appear to be ArchViz and some VR implementations currently. If anyone has more information on this topic I would be interested in seeing it.
(NVidia) Geforce Next Generation Graphics and VXGI (Voxel Graphics Illumination)
Feel free to comment and/or share as this is meant to be an open discussion. :)
Very useful resources for future discussions
thanks
The only question that comes to mind for me right now is:
How do I add that hair to my worrkflow ASAP?!?!?!
Flex, too, but I don't really need particles much. Through I am getting tired of postworking dragon fire... lol
Well you could export your figure to Blender and render in cycles... which would also give cloth soft body physics for your clothing.. and for a free bonus, wind to deform the clothing, hair, grass, trees, etc... ;)
Yeah, I'd happily import into blender and bring it back in to render, but I have no idea how to make hair, and all the tutorials I've looked at are way over my head. I haven't been able to find a store or repository with hair that would work with it, either. Seems like I'm SOL.
Bookmarked - Thank you
Well hair in Blender is a particle based system, so exporting it back to DAZ would end up being a pretty large file. Really it's only a solution for people who are familiar with Blender and plan on either doing their render in Blender Cycles or at least a portion of it, compositing it with something rendered in another engine such as IRay, which has it's own complexities in having the different components blend properly.
The actual reason I mentioned it is that Blender Cycles does have all of these features, so for all of the excitement over IRay, it points out when/where people might want to explore other environments while waiting for said feature(s) to come to their preferred environment.
On a related note, Blender has a well developed node based shader setup similar to the DAZ Shader Mixer. Since the environment in Cycles is similar (with some differences) to IRay and there are many tutorials on doing shaders in Blender, there is some crossover knowledge to be gained by studying Cycles shaders just as people did with Octane (Blender of course being free.)
I'm not getting how the Unreal Engine fits w/ Daz and Iray.
The main interest in iray is the ease of which everything integrates with DAZ. No need to learn an entirely new software. At leasr for me.
As for the Unreal Engine reference, I believe he's just mentioning that it has the capibility to work with Iray, but I'm a little confused too.
Many reasons for the UE4 reference actually. For one, there is a new level of interaction between realtime and non realtime environments. PBR is a new and big factor in both, most environments are looking at new ways to integrate or provide crossover points for the two, and in some cases the line has blurred just a bit more. There is a trend to push this even further, including in the DAZ environment.
People use DAZ for many things, not just still rendering. There are people who use DAZ assets to create their own games and UE4 is as ground breaking on this front as IRay is in DAZ.
Using game environments people have been taking and stitching together clips from their favorite games to tell stories. With new levels of integration between these once disparate environments, it provides a way to do this on a new level where people create their own world rather then having to rely on someone else's game. Amature animators have a new avenue potentially with game engines for recording live performances similar to a digital play.
There is a big push by some to use UE4 for areas such as Realtime Archviz. Areas like this are perfect for premade asset markets such as DAZ. And with UE4 there comes an asset store. Epic sees real value in this and DAZ has probably the longest history of current companies in that area so there are opportunities for potential expansion and integration there.
This integration also provides one bridge to VR. With VR, many of the above points apply, including the fact that many people doing VR are more interested in the VR then creating their own assets. Related to this, I'm sure many people in the DAZ environment would love to have some way to move into VR, so if this bridge does develop in the coming years I'm guessing there would be some happy people here.
Many of the new areas that are developing like indy games, VR, indy animation and film, are more interested in their particular area of interest rather then creating their own assets wherever they don't have to, much like many of the artists here. Finding areas where there are common interests can only strengthen all of our positions in the end it would seem.
Basically, the point of the thread is to look at the current environments and beyond, to synthesis between environments, to what we can take from the various environments to enrich our current one. Hopefully this adds some clarity?
I like to think of this type of discussion as brainstorming, where we let our creativity flow, explore nooks, crannies and corners that aren't always directly related to the end goal but do have some connections.
Unlike What features would you like to see appear in dazstudio 5? which is more directed and with a specific goal in mind, this is meant to be more of a creative free flowing discussion that looks at the underlying tech and possibilities, and in that way sort of acts as a type of feeder to the previously mentioned thread.
I also hope to bring together some references and information directly related to these areas, including IRay, so even if some of the other content isn't of interest to some people, the links and information related to IRay might be.
I'm planning on trying hairworks tonight. I watched a 18 minute tutorial on maya on how to make hair to export of hairworks. I'm going to see if I can export a figure as an FBX, do so maya hair stuff, convert it into hairworks, and then export it back into DS. I'll try to post with results!
That triggered a random thought about FBX/Collada vs Alembic. Since this directly relates to interop between different environements, discussion of what peoples experience with each (along with simple obj import/export) would be interesting.
As far as bringing in geometry from Maya Hairworks, it would face some of the same challenges as those metioned in relation to Blender. It would still be worth trying however to see what you get. It may work well, and even if it proves to be too costly the experience gained will come in handy at some point in the future.
So, take a minute to watch this quick video on Speed Level Design of a Winter Scene in Unreal Engine. I'm sure you will be amazed and find it well worth the few minutes to watch it. Afterwards, post if you would like to use DAZ assets to build your own world you could escape to at times.
I loved world building in various environments over the many years. There is something very satisifying about it for me. While one cannot share their creation without getting all of the necessary commercial licenses, even having it for personal relaxation can be very enjoyable, and who knows, maybe DAZ and the related artists would consider an in-between license for non commercial sharing some time in the future.
* If you found that one interesting, take a minute to check this one out Quick Night Lake Scene.
Hey Gedd - I recently discovered "The Engine" (as it has become known in my house lol).
Quick question. Any idea how one would export a model (with IRAY materials) from Daz so that when one imports the resulting .fbx file, it retains the emissive part of the model? Or do I ahve to add a light within Unreal? Specifically, there's a panel in Stonemasons Sci-Fi Kit 2016 that has lights along the bottom. When I import it into UE, the emissive lights don't illuminate anymore.
Thanks for this thread and any info on this.
In Unity there is an emissive setting on the standard shader material, it is probably the same in UE4. The standard shader in Unity is PBR so basically iRay and I'd be surprised if that weren't true in UE4 too.
Thanks Gedd I will add this to my book marks.
You can't transfer a model with materials attached between different environments at the moment. You have to 'rebuild' materials in the shader in the new environment. This is because of differences in the various environments. This isn't as problematic as it might first seem but there is a bit of a learning curve. I'm sure with time this will be solved, but the community as been talking about 'solving' this for 20 years so who knows. Part of the problem is that the technology keeps evolving, that there are only so many hours availabe for doing development and trying to create a method for moving materials between environments remains a moving target. PBR is providing some much needed standardization and the ubiquity of Substance is now making this much more of a reality, so we may be on the verge of actually cracking this nut in the near future.
As for the emissive, nonesuch00 is right, it is a pretty simple fix really. Take a look at some of the tutorials on the UE4 site and that should do what you need. Also, a quick youtube search on 'emissive materials in ue4' should give you a list of videos to watch if you like that format.
Isn't this the whole idea behind NVidia's MDL (defining materials as opposed to writing shaders)?
"The NVIDIA Material Definition Language (MDL) is a programming language for defining physically based materials for rendering. A rich vocabulary of material building blocks based on bidirectional scattering distribution functions (bsdf) allows creation of a wide range of physical materials such as woods, fabrics, translucent plastics and more. The language is flexible enough to allow applications to add support for popular material models without additional changes in a renderers core shading code, examples would be the Epic’s Unreal physical material model or the material model used for in X-Rite’s SVBRDF model. MDL is defined in a way that it's abstract enough to allow renderers of various architectures to support it. A C-like language for defining texturing functions allows the implementation of custom texturing workflows, texture projections and procedural textures."
https://developer.nvidia.com/mdl-sdk
- Greg
Yes, but I haven't seen an implimentation that allows moving IRay materials between environments except to a limited extent Substance and DAZ. IRay hasn't become well established in other environments and I am under the impression that among other things it's development on shaders is somewhat stagnant. Also, a lot of energy has been going into realtime types of projects like Unity/Unreal and VR/Games/Mobile. A lot is getting split. For instance, high end architectural rendering is still being done in products like 3DS Max with VRay while Unreal is threatening to eclipse it due to the ability to output high quality realtime VR which are the current darling for marketing purposes, even if it's not fully developed as the technology holds so much promise for being able to 'walk around' in a space. Point is, a lot of resources took a left turn.
Thank you kindly.