Ground Strands
Many Ornatrix operators need a distribution surface beneath the strands they work on - to compute texture coordinates, to deform strands with the mesh, and to inherit surface properties. The Ground Strands operator attaches strands that have no surface of their own to a mesh, so the rest of the pipeline can treat them like ordinary surface-grown hair.
A common case is importing curves to use as guides: on their own they float in space with no surface beneath them. Grounding them onto a mesh lets operators such as Hair from Guides Operator generate dense hair from them.
What grounding does
Grounding projects each strand root onto the chosen mesh to find the closest surface point, then stores that surface relationship on the strand. From then on the strand follows the surface as it deforms, and gains the texture coordinates and surface data that downstream operators rely on. Grounding also aligns the strands object with the distribution mesh, so the two share the same space.
Using the operator
- Add a Ground Strands operator to the stack.
- Choose the geometry to use as the distribution mesh.
- Attach the roots, which projects the strands onto the surface.
The strands now follow the surface. To detach them again, release the roots.
Things to know
- Ground strands at the start frame so the surface relationship is captured cleanly before any deformation.
- When projecting, a strand whose tip is nearer the surface than its root may be flipped so it points outward, which preserves its shape but can occasionally attach a strand to an unexpected spot.
Related
- Hair and Guides explains roots and surface dependence.
- Baked Guides and Baked Hair often need grounding after import.