At GDC 2014 this week, Kenneth Yeung from Capybara Games explained how the science of quantum mechanics was used to solve the problem of time manipulation in Super Time Force.
Super Time Force is a 2D Contra-style side scrolling action game from Capybara Games. The central gameplay conceit is the ability to rewind time, allowing you to reply sections of a level. However, your previous actions are layered, ghost-like, on top the current field of play. What’s more, those actions from the past stack and combine with those in the present. Kenneth Yeung, Lead Programmer as Capybara, described the mechanic at his Game Developers Conference talk as “single player co-op”.
Yeung described how the original vision for Super Time Force was to create a simple and fun action game. However once the time-rewind elements were added the game became more complex. Paradoxes were created, and just like the writers of time-travel fiction Yeung and the team had to find a way of making these paradoxes work. They wanted the game to remain simple however, and so looked to the science of quantum mechanics to help them define and solve these problems.
Yeung said that making the game engine was “the easy part”, the difficulty was finding a way to facilitate the intuitiveness of the game’s nonlinearity, or to put it another way, make the effects of the time mechanics make a ‘natural sense’ to the player.
Paradoxes, cause and effect, and entropy all had an impact on development. Ultimately the team had to acknowledge that the decisions they made around these mechanics “may not always make physical sense, but they would feel more correct” to the player.
Yeung explained that the rule of thumb was that, despite the complexities thrown up by the game’s design, there had to an equilibrium between the players actions and the game’s response. No matter what the player did with the time-rewind element the result should never be that “enemies are better off, or the player is worse off”
Classic scientific concepts such as Schrodinger’s Cat also played their part. In Super Time Force this translates into the rule that objects do not exist in the game until they are observed. For example, crates off-screen can’t be destroyed, even if gunfire is pointed in their direction. Again, this may not make physical sense, but it feels correct within the game’s context.
The result is a game that harks back to the golden age of side-scrolling action titles but with a thoroughly modern twist. The application of scientific principles, even if they are bent a little, has allowed Yeung and the team to keep the game simple yet allow for an layer of complexity that remains consistent within the game world and easy for the players understand.
Super Time Force is due for release on Xbox One and Xbox 360 later in 2014.