Abstract: Methods and systems for computing distance data for a structure. A scan surface that represents an inspection area of the structure is identified. A plurality of sample points on an outer surface identified from a model of the structure and a corresponding plurality of projected points on an inner surface identified from the model of the structure are generated using the scan surface, a first geometric representation of the outer surface, and a second geometric representation of the inner surface. Distance data is computed using the plurality of sample points and the corresponding plurality of projected points. The distance data identifies a distance between a point pair formed by a sample point of the plurality of sample points and a corresponding projected point of the corresponding plurality of projected points.