1. A method comprising: receiving, by a programmer, a patient-specific patient anatomy data set that describes at least one characteristic of patient tissue proximate to an electrical stimulation lead having a complex electrode array geometry implanted within a patient, wherein the stimulation lead comprises a plurality of non-contiguous electrode segments located at different angular positions about a circumference of the lead and different axial positions along a length of the lead; receiving, by the programmer, user input that defines stimulation parameter values; generating, by the programmer, a stimulation field model that represents where electrical stimulation will propagate from the electrical stimulation lead based upon the patient-specific patient anatomy data set and the stimulation parameter values; displaying, by the programmer, the stimulation field model in conjunction with a representation of the electrical stimulation lead, the representation illustrating the complex electrode array geometry; receiving, by the programmer, stimulation field input from a user that modifies at least one of a size, shape or location of the stimulation field model relative to the representation of the electrical stimulation lead, wherein receiving stimulation field input comprises receiving input that drags a boundary of the stimulation field; and determining, by the programmer, at least one new stimulation parameter value based on the modification of the stimulation field model.