Frostbite Hair Rendering and Simulation

One of the guiding principles of Frostbite is to be at the forefront of real-time technology. We try to constantly push the limits of what current hardware is capable of. As an example of this, we'll be sharing an in-depth view into one area of our research: hair rendering and simulation.

Our purpose is to produce a step change in real-time hair and reach results close to movie and offline rendering. Starting last year, a small group of frostbite physics and rendering engineers have been working on pushing this technology forward, and, while we still have quite a lot of work ahead of us, we're proud of what we achieved. This wouldn't have been possible without the help of a few amazing Criterion content creators whose assets and constant feedback drove us forward.

This series of blog posts will share some internal details about this new hair technology, and offer a glimpse into how future Frostbite-powered games will look like.

Here's a sneak peek:

In the coming months, we'll publish blog posts about each part of this new system. On the physics side we'll look at our Eulerian/Lagrangian model and its various applications, our different constraints, and our style preservation technique.

On the rendering side, we'll focus on our shading model, multiple scattering simulation and our approach to fine, antialiased hair.

For now, here are a few of the things this new system can do.

Believable natural and artificial coloring

The video below shows dynamic changes of the hair melanin and smoothness parameters, which produces a natural colour change:

This video exhibits a dynamic change of an artificial colouring of the hair:

Volume preservation

Our simulation allows content creators to tweak a large number of parameters to achieve a wide range of behaviors, and we'll discuss this in more details in future posts. For the moment, we'll leave you with this video showing volume preservation amped-up to 11!

Post Authors: Jon Valdes, Robin Taillandier

Contributors to Frostbite Strand Hair Technology: Pedram Karimfazli (Criterion), Jeremy O'Brien (Frostbite Physics), Simon Gomer (Frostbite Physics), Robin Taillandier (Frostbite Physics), Leo Taslaman (Frostbite Physics), Jaco van Dyk (Frostbite Physics), Yasin Uludag (Frostbite Rendering), Jon Valdes (Frostbite Rendering)

A big thank you to Sebastien Hillaire and Charles de Rousiers for their contributions to this product