1. A computer-implemented method, comprising: displaying, by a computer processor and in a graphical user interface, a first user-manipulable control, in response to a manipulation of which a first threshold is modifiable, the first threshold defining an extent to which a volume of activation (VOA) of tissue estimated to be activated by a stimulation is required to correspond to a target volume of tissue to be stimulated; subsequent to a manipulation of the control, comparing, by the processor and to the first threshold as set by the manipulation, an extent of correspondence of an estimated VOA to a target volume, to determine whether the estimated VOA satisfies the requirement: if the estimated VOA satisfies the requirement, determining, by the processor, a set of stimulation parameters that each satisfies at least the first threshold; and outputting the set of stimulation parameters corresponding to the VOA to initiate stimulation of patient tissue using a leadwire implanted in the patient tissue.