Kicking off the list of innovations unique to the PC version, Tomb Raider features a technology called “TressFX Hair.” This technology is the result of months of close collaboration between software engineers at AMD and Tomb Raider’s developer, Crystal Dynamics.
TressFX Hair revolutionizes in-game hair by using the DirectCompute programming language to unlock the massively-parallel processing capabilities of the Graphics Core Next architecture, enabling image quality previously reserved for pre-rendered images. Building on AMD’s previous work on Order Independent Transparency (OIT), this method makes use of Per-Pixel Linked-List (PPLL) data structures to manage rendering complexity and memory usage.
DirectCompute is additionally utilized to perform the real-time physics simulations for TressFX Hair. This physics system treats each strand of hair as a chain with dozens of links, permitting for forces like gravity, wind and movement of the head to move and curl Lara’s hair in a realistic fashion. Further, collision detection is performed to ensure that strands do not pass through one another, or other solid surfaces such as Lara’s head, clothing and body.
Finally, hair styles are simulated by gradually pulling the strands back towards their original shape after they have moved in response to an external force. Graphics cards featuring the Graphics Core Next architecture, like select AMD Radeon™ HD 7000 Series GPUs, are particularly well-equipped to handle these types of tasks, with their combination of fast on-chip shared memory and massive processing throughput on the order of trillions of operations per second.
