A method of heating at least one selected portion of an object, comprising the steps of: projecting, with a device comprising a scanner, an energy beam onto a surface of the object (100; 206) so as to produce a primary spot on the surface, and repetitively scanning the beam in two dimensions in accordance with a scanning pattern so as to establish an effective spot on the surface, the effective spot having a two-dimensional energy distribution, displacing the effective spot in relation to the surface of the object (100; 206) to progressively heat the at least one selected portion of the object, wherein displacing the effective spot in relation to the surface of the object (100; 206) comprises displacing the effective spot following a track featuring at least one change of direction; characterized in that the method comprises maintaining the effective spot aligned with the track by modifying operation of the scanner in correspondence with the at least one change of direction; wherein: - the step of maintaining the effective spot aligned with the track is carried out without pivoting the device around any axis for the purpose of aligning the effective spot with the track, and/or - the step of modifying operation of the scanner is carried out so as to turn the effective spot around an axis substantially aligned with the energy beam, without turning the device and without turning the object (100, 206) around any axis substantially aligned with the energy beam, and/or - the track extends in a plane (X-Y), and wherein the step of modifying operation of the scanner is carried out so as to turn the effective spot around an axis substantially perpendicular to the plane, without turning the device and without turning the object (100, 206) around any axis substantially perpendicular to the plane; and wherein the method further comprises the step of modifying a geometric shape of the effective spot and/or of the scanning pattern (12a, 12b; 12c, 12d) in correspondence with said at least one change of direction. projecting, with a device comprising a scanner, an energy beam onto a surface of the object (100; 206) so as to produce a primary spot on the surface, and repetitively scanning the beam in two dimensions in accordance with a scanning pattern so as to establish an effective spot on the surface, the effective spot having a two-dimensional energy distribution, displacing the effective spot in relation to the surface of the object (100; 206) to progressively heat the at least one selected portion of the object, wherein displacing the effective spot in relation to the surface of the object (100; 206) comprises displacing the effective spot following a track featuring at least one change of direction; characterized in that the method comprises maintaining the effective spot aligned with the track by modifying operation of the scanner in correspondence with the at least one change of direction; wherein: - the step of maintaining the effective spot aligned with the track is carried out without pivoting the device around any axis for the purpose of aligning the effective spot with the track, and/or - the step of modifying operation of the scanner is carried out so as to turn the effective spot around an axis substantially aligned with the energy beam, without turning the device and without turning the object (100, 206) around any axis substantially aligned with the energy beam, and/or - the track extends in a plane (X-Y), and wherein the step of modifying operation of the scanner is carried out so as to turn the effective spot around an axis substantially perpendicular to the plane, without turning the device and without turning the object (100, 206) around any axis substantially perpendicular to the plane; - the step of maintaining the effective spot aligned with the track is carried out without pivoting the device around any axis for the purpose of aligning the effective spot with the track, and/or - the step of modifying operation of the scanner is carried out so as to turn the effective spot around an axis substantially aligned with the energy beam, without turning the device and without turning the object (100, 206) around any axis substantially aligned with the energy beam, and/or - the track extends in a plane (X-Y), and wherein the step of modifying operation of the scanner is carried out so as to turn the effective spot around an axis substantially perpendicular to the plane, without turning the device and without turning the object (100, 206) around any axis substantially perpendicular to the plane;