Crash Course to Karma - Houdini 19

For more resources, and tutorials, visit cgforge.com
In this series of videos, we will be exploring the wonders of Karma - Houdini's new render engine that is out of beta with the release of Houdini 19. Throughout this free series, I'll be going over the basics of Karma, new features in Houdini 19, and a detailed review of everything towards the very end.

[@roachdoggjr722]

Loved this tutorial. Walking through it, right there with us the whole time.

[@wsadxc]

You can create a render region using the 2D Camera (camera icon on the left -> 2D Pan and zoom). Then you can shift drag in the viewport to render region and ctrl + shift + click in the viewport to reset the region.

[@FabianStrube]

Thanks, i really need this to finally start my karma journey!

[@ifaisalstudio]

So glad to see this session 😍

[@tbarsnessvfx]

I think of USD like a well organized storage shelf. Everything in your scene is organized into each shelf automatically. No matter what items your take out to use their location to the storage stays the same. A good example is when you take items like models into your scene. The model stays in the same location on the network even when you publish updates to that model. Maya would do this via references. But that gets messy real quick and requires a multitude of asset management tools to keep things tidy.

[@lolvonlolipopp]

The main pixel sample is probably how many rays we shoot from the camera at each pixel and min/max samples is the range of bounces after the ray intersection.

[@cgforge]

Yeah, that sounds about right. I'm not sure how they are imagining the terminology here, but ill most likely append this series once I get a more complete idea.

[@ToulaLee1]

Thank you so much for this. I am so glad that I don't have to get into the USD world just yet in order to try out Karma.

[@paoloricaldone6273]

thank you

[@enotbert]

Thanks for the video. Karma node is a thing. All those Solaris stuff is so disturbing. Instead of being focused on the final result users have to fit themselves in a new concept.

[@artfive]

Great

[@PaperKrane]

Thank you for this. Totally off topic from the immediate tutorial but will you be updating the ACES installation? I just read that the variable cannot be set in the houdini.env file. Not sure where to set that up now haha!

[@cgforge]

Hmm good question - I'll take a look at it again. For now, try doing edit --> color settings --> color correction --> OCIO Config

[@PaperKrane]

@@cgforge Yeah I tried that too and it wont even load v1.2 .ocio. I have a feeling it's a small bug.

[@cepwin]

Thank you for the video! I noticed something odd....when I look at the karma perspective and have it render it (either the original karma viewport of the scene viewport it shows my object with a bunch of white lines and a circle surrounding it. I can also see the HDRI that I set on the environment light. When I render to disk or render to mplay the background is black, no weird lines and the HDRI is not visible except some reflections on the object Is this how it's supposed to be? It looks like you got your environment background?!

[@cgforge]

Hmm that does sound rather strange. It might be worth looking into the "Background Plate" LOP to get this working properly. Beyond that, I'm not sure what might solve your problem there.

[@cepwin]

@@cgforge Thank you so much!!

[@evanrudefx]

lol, you said something in houdini isn't very intuitive. I feel that accurately describes a lot of things in houdini : )

[@rickvdvulkaan]

You say ''this is probably the way you want to use karma if you are a solo artist'', when talking about the rop, instead of using solaris. Why exactly? I'm really having a headache about ''choosing'' between the obj and solaris. In the launch video from sidefx they showed off alot of cool features like the layout-lop. which you can use to easily ''paint'' objects in your scene. Also alot of other features to manage all your objects and lights are found in the stage level. OBJ feels like a dead end. It looks like they are really going all in with the stage/solaris level, and diving in now could be a smart move when learning houdini. I wish they just had one level with the best of both worlds though.

[@cgforge]

That's a great point with all the new features on the layout-lop. For individual artists, there's a lot in Solaris to love. The reason why I mentioned the ROP context is because you can change things in the sop or object level and see updates in your render. At the moment, if you're rendering in the Solaris layout using your viewport, this is not possible because it jumps out of the render as soon as you switch to the obj context. So, if you want to prevent a ton of overrides from happening in LOPs, it's best to get things as close to what you want in the Geo level first, and then rely on LOPs. I agree that these "two worlds" are a bit jarring - as I mentioned in the final review. In a pipeline, it will take some forethought as to how you want to go about it.

[@magiciseverywhere2]

@@cgforge You can prevent jumping out of Karma render by enabling "not follow selection" pin icon. See image here: drive.google.com/file/d/1t70FlZXu2g1g2VcBdEds0EUkYVApdeU2/view?usp=sharing

[@birdaid5242]

the best way to use karma is in solaris not on the sop level! please refer to the houdini youtube channel for more.

[@cgforge]

In this section, I mentioned that it's best to check your changes on the obj level by using the ROP ipr because changes will not automatically update when switching back and fourth in solaris. The other benefit of doing obj level changes this way is that it forces the stage to re-import everything again once you re-kick the IPR. There have been cases where the LOPs/Solaris context failed to re-import geometry on the obj level, and that situation can be quite confusing when you're trying to make any changes on the obj level. So - within the context of that conversation - it is still the best idea, in my opinion, to update via the ROP context IPR.

[@Kumodot]

karma is ignoring all my cameras, not sure how to make them appear to it.

[@cgforge]

Usually it's something simple like setting your visibility flag to the right location. Or you could try double checking your render settings so that it is selecting the correct one.

[@Aviba]

Its so complicated for such simple things. Coming from Max i am sometimes baffled by Houdini.

[@cgforge]

Houdini has a tendency to make simple things feel complicated and complicated things feel simple. SideFX has also been a company that constantly creates new things / features, and as a result, it can be a bit like sorting through a messy room. Some things relate to older workflows, other things relate to new ones. And the reason why it feels like a messy room is because there are things scattered everywhere based on a variety of ideas that have collected over many years. But, my advice is to understand what you're trying to use Houdini for. It gets overwhelming if there is not a specific goal in mind, but it becomes much more interesting once you focus in on something in particular. I'll be replacing Houdini for the New Artist with an upgraded version once H20 comes out, so try giving that a go if you're interested in giving it another try. Good luck!

[@brandoncyoung]

karma needs to just copy how vray sampling works.

[@erikhall1146]

*Goes Into Solaris* *Houdini instantly crashes* Yeah sounds about right xD

[@job_hobby9752]

А чё в смысле?

[@cgforge]

Это значит, что я научу вас пользоваться Karma.

[@job_hobby9752]

@@cgforge Thank you, Tyler, you never stop trying to teach us how to use this context, but even in version 19 it seems unnecessarily complicated :)