• Team Fortress 2
    Game Production Focus - 1 December 2007


    Valve Software has certainly come a long way since the Team Fortress 2 game appeared on our horizon. Portal 1 & 2, Left 4 Dead 2, Half Life 2, all available under Steam, it's always nice to go back and read how an original game came together.
    CGSociety :: Game Production Focus
    Paul Hellard, from 1 December 2007


    The Team
    Valve is an entertainment and technology software company located in Bellevue, WA in the USA. The company is best known for its ‘Half Life’ and ‘Counter-Strike’ series of games, which to date, have received over 100 ‘Game of the Year’ Awards, and been called nice things like “Best PC Game Ever”, selling over 20 million copies. They recently released The Orange Box, which contains the latest episode of Half-Life 2, a new game called ‘Portal’ and ‘Team Fortress 2,’ a class-based multiplayer game.

    First, some details about Valve Software. “We have around 140 people, although our individual game production teams are usually around 25,” explains Jamaal Bradley, Animator at Valve. “There are no middle managers, assistants, producers, or directors. Instead, we believe in a simple mantra: Whoever designs something, builds it. As a result, our design is entirely collaborative, made up of a wide variety of disciplines, where everyone in the room can contribute to the design knowing that ultimately, they'll be responsible for implementing it.

    As a result, we look for highly self-motivated production folks who care about the product as a whole, and are able to prioritize and choose their own constraints, so they can work effectively when someone isn't there to manage them. We've hired veterans from places like Blizzard, Pixar, WETA, Sony Imageworks, ILM, Blue Sky, and DNA. Conversely, we've picked up motivated youngsters who've built interesting and innovative games, from FPS mods to college projects. We hire for the long term, not to fill some number of production slots.”
    Team Fortress 2 Background
    Released in 1996, the original game ''Team Fortress'' was a team-based multiplayer ''Quake'' mod developed by three Australian college students. ''Team Fortress'' popularized the notion of class-based multiplayer gaming, in which each player chooses to adopt an explicit role, usually defined by unique weapons and abilities.

    Since it was a mod developed by a small team of students, the original ''Team Fortress'' had no real art direction beyond the look defined by ''Quake''. In 1998, the ''Team Fortress'' mod team was hired by Valve and produced the next incarnation of the franchise in the form of ''Team Fortress Classic'' using the technology of the ''Half-Life'' engine. Again, the team chose a modern realistic military style, but combined it with a saturated cartoon color scheme.

    ''Team Fortress Classic'' was built on a very quick schedule in just three months, so the team didn't have the time to try out alternative visual approaches, but that would all change with the development of ''Team Fortress 2''.

    The initial art direction of ''Team Fortress 2'' again focused on a realistic contemporary military style, with all of the usual camouflage gear, tactical helmets, combat boots and hardcore weapon detail. After play testing the game, however, the team came to a crucial realization: the gameplay and art direction were fighting each other. Some of the most basic multiplayer problems, like visually identifying other players against the scenery, were failing.

    In the real world, soldiers do everything they can to avoid being seen but, in multiplayer games, this can ruin the fun. Real world soldiers also wear uniforms, which tend to make them all look alike. Again, this conflicted with the core gameplay of ''Team Fortress 2'', which has nine distinct character classes. It is critical for players to be able to tell the classes apart at a glance, even in a darkly lit environment or at such a great distance that they end up just an inch tall on the screen.
    Beyond the visual differentiation of the classes, the ''Team Fortress'' franchise features a number of gameplay elements that make no sense at all in the realistic military world. For instance the medic class can shoot a healing beam into another player in order to boost the other player’s health. Right off the bat, a weapon that a player shoots at his teammates is a challenge for the player wielding it to understand.

    Then there are surrounding problems, like enemies needing to understand that the guy they're shooting at, is being healed by the medic via his healing beam. There weren't enough generally recognizable clichés that the team could leverage in the realistic military world to help players understand what they were looking at in these cases.
  • Art reDirection
    Because of this issue with the medic beam and a number of other similar challenges, the team decided to rethink the game’s art direction. The team enumerated all of the gameplay problems that more deliberate art direction could solve, right down to the specific details of the most outlying weapons, characters and objects.

    From this list, the ''Team Fortress 2'' team was able to extract high level goals for a new art direction. First off, the new art direction needed to be exaggerated, to match the over-the-top combat style of the game. It also needed to focus on incredibly unique characters, yet still ensure that the classes looked like a cohesive team when shown together. Additionally, the art direction needed to support a variety of unrealistic weaponry and a variety of player goals, from collecting objects to holding territory.

    On top of this list of gameplay requirements, the team identified important product requirements such as the need to stand out visually from Valve’s other products, not to mention the competition. The look needed to be inspirational and it needed to project "fun" rather than "hardcore." With all of these design goals and constraints in hand, the team would be able to evaluate the fitness of proposed concepts as they went back to the drawing board.
    Visual Design
    Due to the importance of the nine character classes to the gameplay, the team focused on them first. They established a "read hierarchy", a prioritized list of the information that players needed to extract from the character model. From most to least important, this was: the player's team, the player's class, and the player's current weapon, which usually implies the player's intent in our game.

    They used the model color palette to represent the team, a somewhat suboptimal solution for varying lighting conditions, but a good tradeoff given the technology constraints. “We found that silhouette and animation were better long-range identification characteristics than texture detail or color,” says Jamaal Bradley, “so we used those for class identification. Finally, we tackled the weapon by using contrast and color gradients to draw the player's eye to the chest area, where the weapons are held.

    ”“We tried out a variety of implementations before settling on our final one. Once we had it on paper, our artists worked closely with our engineers to invest in technology that could deliver the desired visuals. The shading techniques were designed to quickly convey geometric information using rim highlights as well as variation in luminance and hue, so that game players are consistently able to visually 'read' the scene and identify other players in a variety of lighting conditions.”
    Inspiration
    The crew used a variety of different references to help understand illustrate visual goals. In particular, the three commercial illustrators J. C. Leyendecker, Dean Cornwell and Norman Rockwell were primary sources of inspiration. These artists were known for illustrating characters using strong, distinctive silhouettes with an emphasis on clothing folds.

    They tended to use shading techniques which accentuated the internal shape of characters with patterns of value, while rim highlights rather than dark outlines to pull their silhouettes out of the background. Other principles included making sure the shading obeyed a warm-to-cool hue shift, and shadows going to cool and not black. Ensuring that saturation increased at the terminator with respect to a given light source, where the terminator is often reddened, and being selective in omitting high frequency where possible.

    Some of these became design principles whereas others, like the saturation and reddening at the terminator, led to specific shader features implemented and used across the board.

    Character Development
    Each of the character classes needed to be visually distinct from one another in a world where there is little control over the circumstances, and none over the camera. “We spent a long time designing just the silhouette shapes so that, when viewed only in silhouette with no internal shading at all, the characters are readily identifiable to players from all angles,” says Jamaal.

    “While we do have control over the lighting, and worked to ensure our characters never appeared in such unflattering conditions within the game, we used this method to validate the character designs at the concept phase. We focused on using the body proportions, and weapon lines produced by footwear, hats and clothing folds to explicitly craft a unique silhouette for each character.

    In the shaded interior areas of a character, the clothing folds were explicitly designed to echo specific shapes in order to emphasize silhouettes, as observed in the commercial illustrations which inspired our designs.”

    “We found that silhouette and animation were better long-range identification characteristics than texture detail or color.”


  • World Creation
    The visual design of the environments is borne out of similarly well-defined design principles. The maps are usually made up of two enemy bases separated by a neutral space. In particular, the bases tend to be unrealistically near each other, as if each team somehow built a fortress without noticing their enemies doing the same on the other side of the road. “Fictionally, we focused on the idea that each base was the classic spy fortress, hidden by an innocuous façade,” explains Jamaal.

    “We wanted unique visual designs for each area so that players could see at a glance where they where in the overall space. For the architectural elements of the world associated with each of the two teams, Blue and Red, we defined specific contrasting properties. While the Red team's base tends to use warm colors, natural materials and angular geometry, the Blue team's base is composed of cool colors, industrial materials and orthogonal forms.

    We maintained a minimal level of repetition and visual noise, and used an almost impressionistic approach to modeling. This was designed to help the characters stand out against the background, allowing players to quickly spot enemies.”


    “This impressionistic philosophy was also central to our texture painting style throughout the game. Much of the world texture detail in TF2 comes from hand-painted albedo textures, which intentionally contain loose details with visible brush strokes, intended to portray the tactile quality of a given surface.

    In the early stages of development, many of these 2D textures were physically painted on canvas with watercolors and scanned to make texture maps. As we refined the art style of the game, texture artists shifted to using photorealistic reference images with a series of filters and digital brush strokes applied to achieve the desired look of a physically painted texture.

    Not only does this hand-painted source material create an illustrative NPR style in rendered images, we have also found that these abstract texture designs hold up under magnification better than textures created from photo reference, due to their more intentional design and lack of photo artifacts. Furthermore, we believe that high frequency geometric and texture detail found in photorealistic games can often fight the designer's desire to both compose the environment and to emphasize specific gameplay features.”
    Creating with the Cabal
    Cabal is the name of Valve ’s internal design and production process. It's built around the concept of cabals, which are usually small groups of four to six people, of varying disciplines. A cabal is formed to solve a specific problem, which they'll be responsible for both designing and then implementing. “We find this simple rule, that whoever designs something builds it, solves a variety of issues surrounding ownership, investment, and prioritizing,” explains Jamaal.

    Most important is that the cabal contains a spread of disciplines, so that it uses the right tool for the job. Some problems that take weeks of programming can be done in a day of animation, or vice versa. The crew finds cabals to be the most effective process for tackling problems that are a collision between creative choices and technology and resource constraints.
    Meet the Team
    When Valve decided to introduce the characters to the world, they knew the most important thing was to create something that was appealing. “Although it is a fantastic feeling to escape into another reality,” says Jamaal, “we thought it would be better to connect with characters that have familiar behaviors and personalities. Even with some of there extreme absurdities, there are several identifiable attributes in each of the nine classes.

    The animators had to pull from the existing behaviors that were setup in the game, but the big advantage there was the animators that created those were the same animators that would work on the shorts. And not only would the animators get to create the performances, they would also direct the segments. The end result would be the game driving the movie character traits and the movies driving some of the game behaviors.”

    Team Fortress 2 has come through many iterations and the dev team’s sights were set on something that would push them as artists, designers, and engineers. Building a game on design and artistic principles to enhance the experience of gameplay has proven to be an effective way of making an even more cohesive product that excites the players. “Creating TF2 is something that is broadening our scope to various avenues of design, and methods we can take to future projects,” says Jamaal, finishing up. “Ultimately we had fun making, playing, and seeing the public enjoy the final results of our work.”
     
    Related Links:
    Orange Box
    Valve Software
    Steam Powered
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