1. A system for surgical imaging and display of the type indicating tool position together with an image of a patient undergoing surgery, and including a display and an image processor for displaying such image in coordination with an image of the tool for visual navigation of the tool during the surgical procedure, the system being configured for use with a fluoroscope that includes an x-ray source and an imaging system, and such that at least one image in the display is derived from the fluoroscope at the time of surgery, wherein the system comprises: a fixture including a three dimensional array of markers and adapted to be rigidly affixed to a fluoroscope for automatically imaging the array of markers as a fluoroscope image is acquired with the fluoroscope; a tracking assembly including a first tracking element associated with the tool and a second tracking element associated with the fixture, the tracking assembly being effective to automatically determine relative position data of the marker array and the tool; a marker determination unit operative on the fluoroscope image to identify a subset of said markers in the image; a processor operative with said identification to calibrate the system; and a correction unit responsive to the system calibration and to said position data to determine an image transformation such that a representation of the tool is correctly positioned and oriented in the fluoroscope image.