[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: Creating Believable Hair and Fur
Michael Svymbersky, 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.]
Without a doubt, hair is among some of the hardest things to get right in computer graphics. CG hair should unify the character and not be noticeably distracting to the viewer/player. It’s a technically and artistically challenging endeavor as we never want hair to look like a wig but that it belongs to the character. It’s an important thing to get right because creating believable hair can go a long way in enriching particular details about a character’s background and/or place in the world. As such with Rise of the Tomb Raider we spent a great deal of effort to bring our characters and animals alive by creating the appropriate hairstyles and fur patterns.
When creating hair and fur for all of our non-player characters and animals we use the method of Alpha Card creation and arrangement. Alpha Cards are geometry planes that have the shape of individual clumps of hair. Applied to these geometry planes is a texture that can be broken down to its most important parts: the Color map and Alpha map.
The color map, is a painted/photo-sourced texture, while the Alpha map dictates transparency. The color black will tell the texture to render invisible while the white color will stay visible. With the texture and arrangement of cards, we can nail the appearance of hair.
The shader tells our game engine how to render the object. It will use all the textures we input to control the highlights and lighting conditions that are in effect.
The arrangement of these alpha cards are the key to this whole process. Many artists have different workflows, but the most tried and true method is the manual placement and evaluation for each individual Alpha Card. We place the cards down to fill out the character and to add the appropriate silhouette changes. Regardless of the content that we are creating, the same techniques are applied across the board for animals, character hair, beards and props.
As demonstrated on the bear, we are manually placing the Alpha cards on the model, creating the texture and adjusting the shader for correct highlights. It’s a very back and forth process and we go through multiple iterations before achieving the final look.
Hopefully this gives you a little peek behind the scenes for how we approach hair and fur. We believe that it’s these little nuances that achieve a believable presence and help ground these characters into the Tomb Raider world. While it’s an artistic and technically challenging endeavor, it is also one that’s very rewarding to see in Rise of the Tomb Raider.
Michael Svymbersky
Character Artist, Rise of the Tomb Raider
