a method for determining 3d distances on a 2d pixelized image of a part or object includes acquiring a real 2d pixelized image of the object , creating a simulated image of the object using the 3d cad model and the 2d pixelized image , determining a specified cost function comparing the simulated image with the real 2d pixilated image and repositioning the simulated image in accordance with iterated adjustments of a relative position between the cad model and the xid pixilated image to change the simulated image until the specified cost function is below a specified value . then , the workstation is used to generate a 3d distance scale matrix using the repositioned simulated image , and to measure and display distances between selected pixels on a surface of the real image using 2d distances on the 2d pixelized image of the object and the 3d distance scale matrix .