FUNDAMENTALS OF GAME DESIGN, SECOND EDITION
Gameplay and Victory Conditions
The primary challenge in playing any vehicle simulator is in controlling the vehicle: learning to speed it up, slow it down, and steer it without crashing it into something. Without being able to feel the G-forces on his body, the player has to depend on other cues to determine how fast he is going and how hard he is braking.
In the case of flight simulators, you can make this challenge simple, requiring the player to know almost nothing about aerodynamics, or extremely difficult, accurately modeling the behavior of an airplane. Unlike a car, airplanes respond rather slowly to their controls, often beginning to execute a maneuver a few seconds after the player has first moved the yoke or joystick. Players used to driving a car will
tend to overcontrol the plane when they find that it doesn't respond immediately.
If you want to present a realistic challenge, you can model this problem accurately; to keep the game easy, treat the plane more like a car.
In military flight simulators, the player must not only fly the aircraft but also achieve the mission's objectives, usually attacking enemy aircraft and ground installations. Modern air-to-air combat, conducted with long-range guided missiles and often directed by Airborne Warning and Control System (AWACS) planes, is a rather cerebral exercise. Hence the continuing popularity of World War I and II flight simulators and fictional battles such as those in Crimson Skies (see Figure 17.1). These let the players dogfight, twisting and turning through the sky, hiding behind clouds, diving out of the sun, and blasting away with bullets at short range. It's a much more action-packed experience.
The role of the aircraft being simulated defines the gameplay for military flight simulators. Fighter planes are designed primarily to attack enemy aircraft and to protect friendly aircraft and ground units from air attacks; attack planes are designed to attack moving ground targets; bombers are designed to attack stationary ones. Most military flight simulators offer a series of missions, often with primary and secondary objectives such that achieving either or both of them constitutes victory. Being killed or having the player's plane shot down constitutes a
loss. However, you don't have to establish binary victory conditions; you can allow for partial success by rating the accomplishments of a mission according to the number of objectives achieved, the length of time it took, and the amount of damage sustained by the aircraft, for instance. You can also assign bonus points for a swift and safe return.
Civilian flight simulators such as the excellent Microsoft Flight Simulator (see Figure 17.2) seldom include any victory conditions unless they implement racing or tests of flying ability. Many of them simply let the player fly and try different things with the aircraft rather than present him with a specific mission to accomplish. However, civilian flight sims can present a wide variety of challenges: flying at night; flying in rain, fog, or strong winds; and using visual flight rules or instrument flight rules. Landing smoothly and safely, particularly in adverse weather conditions, is always the most dangerous moment in a flight and usually represents the toughest challenge that a civilian flight simulator offers. Most provide an autoland function that simply returns the plane to the ground without the player's having to perform the landing.
Organized racing simulations, like sports games, take their gameplay from the real thing. The challenge is primarily to win races without crashing. This may be just as complicated as real racing, including such details as refueling, managing the tires, and compensating for the weather. Some games also include an economic element: The player wins prize money for doing well in a race, and the prize money enables her to buy better equipment. This produces positive feedback that must be counteracted to balance the game; as the player improves, her artificial opponents must also improve to offer her a worthy challenge.
In more arcadelike driving games, the games often include other challenges such as running other drivers off the road, gathering up collectibles or power-ups, weaving through hoops or cones, shooting at enemies or dropping devices to delay them, and so on.