[目录] [Building the Myths of Rise of the Tomb Raider] [Finding Inspiration for Rise of the Tomb Raider] [Research and Reference in Rise of the Tomb Raider] [Building from Life] [Creating Believable Hair and Fur] [Creating Believable Materials] [Creating Believable Skin and Character Material Effects] [Creating Motion and Emotion with Animation] [Bringing Lara to Life with Blendshapes] [Physically Based Rendering and Post Effects] [Building Larger Worlds with More Fidelity] [Snow Tech and Houdini Simulations] [Scoring Dynamic Combat with Procedural Music] [“I Must Not Fear”] [The Bear Chase] [Rise of the Tomb Raider for Stealth Gamers] [Rise of the Tomb Raider for Puzzle Gamers] [The Evolution of Tomb Raider Hubs] [Expedition Modes] [A Little Thing About A Little Thing]
Dev Blog: Bringing Lara to Life with Blendshapes, PBDs, and Spline-Based Hair
Kam Yu, Lead Character Artist
[Leading into the launch of Rise of the Tomb Raider, we’ll feature a variety of developer blogs that lift the curtain on the creation of Lara’s first great tomb raiding expedition.]
The facial animations in Rise of the Tomb Raider utilize some of the latest blendshape technology in video games. With this system we are able to capture every nuance in an actor’s performance and bring it to life on our characters.
In the past, facial animation was dependent on a system of bones that drove the mesh. The more intricate the facial shapes, the more bones you would need to get the desired results. The whole skeleton would often become very large and cumbersome.
With blendshapes, though, we’ve eliminated the need for bones. Instead, Lara’s facial expressions are broken up into discreet shapes that can be animated in combinations to achieve a very life-like performance. Lara herself uses over a hundred different shapes to define her facial movements. Through this system, we are able to animate even the smallest of details on her cheeks and forehead. Even Lara’s eyelids follow her gaze as she looks around.
Pictured below are some of Lara’s blendshapes.
Another way we enhance the realism of blendshapes is through the use of wrinklemaps. These are specific maps that we apply to certain areas of the face to give the impression of surface changes in the skin. Wrinkles can be made to appear along with changes in blood flow (redness).
A wrinkle map on Lara’s forehead below is used to emphasize the surface detail.
Pose-Based Deformers
Pose-Based Deformers (PBDs) are correctives that are used to achieve a specific deformation on the body that skeletal weighting alone cannot attain. They can be used to fix any stretching that occurs when the mesh is posed. They can also be used to show muscle flex. Another use is to create the broad folding on clothes when a character bends a joint.
In the images below, the shape of the shoulder was corrected using a PBD. On the left is the shoulder with weighting only. On the right is the corrected shape.
The shape of Lara’s arm was refined using PBDs, as shown below.
Often, the PBDs are used in conjunction with wrinkle maps to show more detailed surface changes. The wrinkle maps are either derived from scans or high resolution sculpts.
Pictured below is Lara’s knee with PBDs turned on (left) and off (right). You can see how the wrinkle pattern changes when the PBDs are turned on.
The following is a render of the vertex color activation on the leg. Red indicates where the compression map will be displayed while green indicates the expansion map.
Spline Hair
Lara’s hair is very unique in video games. Video game hair is usually comprised of polygonal alpha cards arranged in a manner that simulates hair volume. Lara’s, on the other hand, is made of actual strands. There are over 30,000 strands of hair on Lara’s head. These in turn are controlled by a series of master strands. It’s the movement of the masters that drives the individual hairs making them react naturally to the physical forces in the game.
Lara’s hair will react differently in various situations due to specific “profiles” that are scripted. For example, her hair will become more stiff and heavy when wet. It will also become buoyant when Lara is submerged under water. The ponytail will bob from side to side when she is running. The way the hair reacts to movement is very close to what you would see in real life.
The following is a screenshot of Lara’s spline-based hair.
Blendshapes, wrinklemaps, pose-based deformers, and spline-based hair all combine to make Lara feel more alive than ever before.
Kam Yu
Lead Character Artist, Rise of the Tomb Raider
