One of the touted features of Grooms is the ability to auto-generate cards for your groom for LOD purposes. I can’t for the life of me get this working (I can generate the cards but they’re untextured). I’ve also looked for tutorials but haven’t found any.
Does anyone know how to do this?
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Any movement on this? I’m curious about it too.
Sounds like Total BS to me.
Hair cards need a lot to work correctly, including a flow map which is predicated on a UV of the whole set unwrapped within it.
Yea, in theory you could sort of do it with vertex colors. In practice you need at least one vertex color channel to do other stuff, so you can’t.
On the other hand, grooms have never worked right since release…
Also, to get from a texture to a card in an “automated” process of any sort, you would need to shoot and bake the hair render onto a texture - the engine doesn’t write files to disk that way, so pretty sure it wouldn’t work.
You’d have to manually save out the result of a render target or have a pyton powered script do so.
All in, I have always suggested that evereone should learn how to make their own hair cards…
Yeah, it’s just weird that it was a feature that they talked about. There’s even a button to do it, but as I said, it doesn’t work. I just ended up creating my own cards. Sad though.
Out of sheer curiosity.
Did the generwtion thing make UV mapped cards or were they just geometry?
Its probably useless since it doesnt make the require work any easier, but if the cards happen to be UV mapped, maybe its possible to hack a texture in there…
It’s been so long since I attempted to do this. I’m pretty sure it just made the geo without UVs, but don’t hold me to that statement 
*Oh, actually I found the original file on my HD. It does indeed have UVs:
I think I remember the issue was that it didn’t render the material properly in the editor. Like the strands were too thin and wouldn’t show on the cards.
It’s strange there’s no documentation for this.
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It DOES work you are mis-understading what the promise was. The idea as that for MOST of the hair Grooms upon launch, there would be high end Strand Groom and accompanying Cards that can be used alternatively. (The button you speak of (Checkbox) But this is not to turn the grom INTO a Cards it is to make use of the isting Cards avaiable (or not ) for the given Groom. There caveat being that for some of the hair Grooms, there are only 0 and 1 LODs (and though it does not say so, the same is true for Cards for those particular grooms.).
So for most of the Grooms the Cards work, but theGrooms with no Cards (and LODs only for 0 and 1) are the ones that generate the YELLOW Text Warning in Bridge.
Sorry, I’m not understanding what you’re saying. It sounds like you’re saying that it’s going to use existing cards instead of the groom at different LOD levels, but that’s not what I’m talking about. The engine has the functionality to create the cards for you, as I’ve shown. It literally generates cards based on the groom. It also creates textures for you but they are blank. It is like the process of baking the groom data isn’t working.
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As far as I have ever known with Metahumans, The only time it ‘Automatically Generates Cards’ is when you GENERATE a MetaHuman. The cards are avaialble to use when you switch to them. Some Hair come with the WARNING that LODS exist only for LOD 0&1. Those same Grooms NEVER come with CARDS. Whatever cards are availabe (OR NOT) are then set at that time. THE PROOF IS THE FACT THAT YOU YOURSELF HAVE CARDS FOR SOME but NOT OTHERS.
------> Are you referrring to the experimental Card Generation that was introduced in 4.26? Easy fix if you are importing Grooms or Alembic: Install 4.26,
import your Grooms, make cards for them then Migrate the Groom and Cards to your 5.1 or 5.2 project
YES I know you can’t get a Groom to go from 5.2 to 4.26 to ‘Card It’… BUT Maybe you can!: (I did some research for you, I never like to take No for an answer 
(5254) Ornatrix UE: Procedural groom export in UE5 - YouTube
Maybe theres some sort of language barrier or something.
We all appreciate the posts and you trying to help, but the funcionality @TorQueMoD is after was broken in .26 as well.
Would be really nice if it wasn’t maybe.
Then again by now I have a hair salon set up in blender that even bakes the flow map out, so i don’t particularly care anymore myself…
Really, the one misunderstanding is you.
Perhaps try to re-read the original posts and actually understand what was being tested.
You know, before making other Assumptions…
I’ve also moved past it. It’s easier to manually create your hair cards and skip the option entirely. Would have been nice to have an auto generator though
It’s been so long that I’m getting two different projects muddled together
I thought this conversation was about my custom groom imported from Blender for a non-MetaHuman character, but apparently, in my title I put (metahuman) in parentheses. LOL
So regardless of whether or not you use MetaHuman, when you have a groom in the editor (not in MetaHuman creator, in Unreal Engine itself), there’s an option to convert the groom to cards (yes, the experimental card generation). The engine will generate the card meshes for you (the UVs I posted were from a Werewolf character with a custom Blender groom) and supposedly will bake the groom onto said cards so that you can use them as a distant LOD and it will look the same as your groom. The functionality seems broken though because it will generate the cards for you and UV map them, but the textures don’t bake properly. It did create textures for me, but they were blank. I did also get some really thin hairs showing on some of the textures, but nothing was visible in the game, so I posted here to see if anyone else knew the workflow. If there was a way to increase the thickness of the groom hairs during the bake, it might fix the problem. There is no documentation that I could find covering baking the cards, so I assumed it was supposed to just work. I was also talking about UE4.26 when I posted this. I’m not using UE5. You video is a tutorial on how to export a groom from UE5 which is not at all what I’m talking about.
Since the grooms are so intensive anyway, I was thinking this would be a good method for creating a custom groom in blender, then bringing it into UE, baking it to cards, and then just using the cards as they are more performant.
Id suggest skipping grooms altogether and using Blender’s hair to comb the cards directly.
There’s a somewhat hidden option that will align the mesh with the hair particle, including respecting the particle’s lenght.
This allows you with some styling work (which is a nightmare even for a hair stylist, had one try) to directly edit and curate the cards to use in engine without needing the groom.
Usually, we make the hair cards an apex cloth material with a dedicated (vertex color driven) mobility value thats rather low but enough to add some visual feel (If you prevent self penetration it works best, but costs more).
The flow maps are also somewhat important to bake, for complex grooms at least. So anyone wondering why the material doesn’t look quite correct should try out setting up flow maps in the material (and baking a flow map out).
Even with cards, .24 had issues with point lights and lighting hair in general.
This could all still be true even in 5…
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Hooray! They’re finally working on updating the tool!
It takes a good 5 minutes to restart the editor after you enable the tool, but at least it works
Also, if you’re using the hair that comes with Metahuman, they already come with all the cards automatically created. You just need to open your groom and switch whatever LOD you want to be cards to “Cards” instead of Groom. You can also duplicate the groom and set all of the Strands to Cards for a cards-only version of the Groom.
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