On our groom assets we were wondering how we can use the Groom/Hair Group Index feature on cards that are made without strands and without the hair card generator plugin? Groups appear to work with the strand hairs that we’ve made but we haven’t found a way to get them to work with cards yet.
So far we have been using separate card meshes with their own materials instead of using the group index to drive some parameters for that group. I haven’t been able to find how this works elsewhere but feel free to redirect me if there’s explanations for how the groups work somewhere already.
Thanks for your question. Do you have a simple example of what do you want to achieve? We have 2 kind of grouping here. The strands groups which you can see in the groom asset details and used for physics, interpolation… And the cards groups which are usually set on strands when building them from maya/houdini…the cards groups are usually used to create all the cards in the generation pipeline. So in your case do you want to override the strands at strand group 0 for example with a given card mesh for LOD1 and to override strands at strand group 1 with another card mesh for LOD1? Thanks, Michael
Hello! As far as I know there is nothing in place allowing to create custom groups. The simplest solution seems import a strands groom (it could be just a few strands aligned on your cards or something like that) and select cards geometry for all LODs. This way you can create & split groups as you want to and still have a card-only groom.
In your favorite DCC tool, create a strands groom, with only a few strands (e.g., a strands per cards, or even less). Assign the strands to various groups as desired, in order to obtain the desire group structure (1/2/3/… groups). If you need simulation, you can also add simulation guides.
Export this groom as alembic file
Import this into the engine to create a groom asset. The groom should now have the correct group structure.
Add the cards meshes into you groom asset and assign them to the precreated group structure.
For the card deformation you can either use the generated card guides, or you can use the imported strands if they aligned will enough with the cards.
Hey sorry for the delay! I missed the notification
Basically our artists wanted to use the groups so that the group index pin used by the hair attributes material node would output something that we could use to do things with (like tint groups differently).
We’re only planning on authoring strands for characters in cinematics. For everything else in gameplay we’re only going to be authoring cards directly in DCC. They were trying to set the group index on the Cards tab (pictured) to see if it would be picked up in the material, or trying to find a way to embed it in the cards or textures they make in dcc so that it could be read by the material later.
If I’m reading you correctly it sounds like neither of those would work here. If so is there an equivalent way to do that?
Let me know if you need more details![Image Removed]
Thanks! Would you have a simple example of how to set that up? I passed this along to our artist and he gets the concept but isn’t sure how to approach it exactly with the tools available