A method for mapping, consisting of receiving an initial set of measured values of a physiological parameter, which were measured at respective locations in a body organ and receiving a three-dimensional (3D) map of the organ including an array of spatial map elements. The method includes forming a correspondence between the respective locations at which the measured values were measured and a sub-group of the map elements, and in response to the correspondence, associating respective element values of the physiological parameter with map elements other than the sub-group. The method further includes adjusting the respective element values so that contiguous sets of the map elements form a geodesic, and displaying a map of the organ showing the adjusted element values.