On The Job Hair Card Generator

On The Job, is a series of shorts produced by Noggin to showcase different jobs, and teach kids foundational skills along the way. While it was a wildly successful project, our timetable for producing episodes was very short. Typically a character only had 2 weeks after the design was locked to be modeled, textured, and rigged. Usually design was updated a week into it.

We were curious what a hair system might look like, but given the constraints, we settled on a test of hair cards. The goal was to build a system that would allow for cards to be created by anyone on the team and for results to be fast and art-directable. We were forced to move on, but it still presented some fun challenges and an interesting result.

I built the system in Houdini, but never got to the HDA. It took a base geo, and from there cards were automatically oriented on the surface. Using a vector brush hair flow could be refined. A series of parameters could be promoted to allow stilizing.

The most interesting bit in my opinion was how the system dealt with the final hair card renders. Similarly long hair was lumped into groups, these groups shared UV islands. Then a Houdini hair system was generated on top, and parameters were adjusted to achieve the final look. At this point, the hair could be previewed within Houdini. The vast majority of parameters could be adjusted without recalculating the UVs or rerendering the hair. This would have given artists a better view of the final result while working.

CG Generalist | [email protected]