1. A method implemented by a computing device, the method comprising: detecting, by the computing device, an input comprising a plurality of parameters; determining which gesture of a plurality of gestures the input corresponds to based at least in part on the plurality of parameters; wherein the plurality of gestures include: at least a first gesture defined by a first parameter with a first threshold that varies as a function of a second threshold of a second parameter, such that the first threshold increases when the second threshold increases and the first threshold decreases when the second threshold decreases, and at least a second gesture defined by a third parameter with a third threshold that varies as a function of a fourth threshold of a fourth parameter, such that the third threshold decreases when the fourth threshold increases and the third threshold increases when the fourth threshold decreases; and causing an operation to be performed that corresponds to the determined gesture.