Do you hate painting hair cards by hand?
The Hair Card asset only requires the free version of Houdini (Apprentice) and Substance Designer for baking an opacity mask. More importantly, Substance Designer provides group baking by mesh name, which Houdini doesn’t do. Group baking by mesh name isolates baking to specific meshes in a 3D scene as opposed to baking everything high poly to everything low poly. This is CRUCIAL to baking a high poly hair mesh to low poly hair cards. As you can imagine, baking an entire head of hair onto a cluster of hundreds of hair cards would produce a mess. Substance Designer’s “Bake By Mesh Name” feature allows us to bake individual cards with their high poly clump counterparts assigned to them without interference with surrounding hairs that belong to other hair cards. Houdini doesn’t allow this so that’s why we need Substance Designer to get a cleaner bake.
Make a hair style using Houdini’s hair system and have that prepared. Plug in each hair generate node into the Hair Cards asset. Make sure the hair generate nodes have a hairclump node inside the graph. The hair cards asset REQUIRES a clumpid attribute that the hairclump node initiates. Adjust the sliders to suit your tastes and scalp’s needs. The first output on the left will output a low poly hair card mesh. The second output on the right will output a high poly hair mesh made from Houdini’s hair system. Export both as a .obj then proceed to bake in Substance Designer clicking “by mesh name” for each map.
Follow this link to find the full guide and documentation.