1. A computer-implemented method for designing a wireless power transfer system, the method comprising: through a computer-implemented user interface: defining one or more attributes of a source resonator and a device resonator forming the wireless power transfer system; defining a relative position and orientation between the source resonator and the device resonator, wherein the relative position is defined in three-dimensional coordinates; and defining a range of a sweep parameter which determine conditions of the wireless power transfer system; calculating, using a processor, an electromagnetic performance of the wireless energy transfer system for the conditions determined by the range of the sweep parameter; and generating, through the computer-implemented user interface, a visual representation of information about the modeled electromagnetic performance of the wireless energy transfer system based on the range of the sweep parameter.