L'Oreal virtual hair… because your games are worth it

OK now that the bad advertising pun is out of the way, here’s the science bit…

L’Oreal have been working with the games and film industry and claim to have come up with a world first: an accurate way to map and animate lifelike hair for CGI games and films.

As anyone who’s struggled with their hair will testify, it’s very complex. In fact, there are between 120-150,000 strands of hair on the average head, which means a lot of processing power for a computer to model, and great difficulty in making it look realistic.

Apparently this benefits both industries. Films and games will get more realistic hair modelling, whilst L’Oreal will be able to see what happens to hair when various parameters are modified, and develop new products from it.

Over several decades, L’Oreal had built up a database of knowledge detailing all the parameters expressing the properties of a single strand of hair. The challenge came in translating that into a whole head of hair, where individual strands interact with one another, with the head and shoulders. Initial animations were unrealistic, so the team developed a static hair model whereby they mechanically animated 100 to 200 master hairs, depending upon the hair type, and then used a combination of interpolation and extrapolation to achieve a whole head of hair including hundreds of thousands of individual hairs.

They then proceeded to try and implement a dynamic model, whereby they reworked the single strand of hair model by using arcs called superhelices to describe the hair, instead of rectilinear rods. This solution is more difficult to implement, but has the advantage that only a few elements are required to reproduce complex movement. The final, dynamic, configurable model was unveiled in the Spring 2006.

It was then presented to the 2006 Siggraph (Special Interest Group on Computer Graphics and Interactive Techniques) in Boston and welcomed by the profession as a world first worthy of interest.

So, expect more realistic hair in future games and films, thanks to L’Oreal.