A computer implemented method for determining the bounding box of a computerized graphic shape comprising more than one vectorial primitives described in vectorial mode, wherein the bounding box is calculated by applying analytical mathematical formulas to the vectorial description of the vectorial primitives constituting the shape without preliminarily performing a phase of drawing and displaying of the shape through resolution of the vectorial primitives that compose it, the method comprising: calculating the bounding box for each vectorial primitive, and combining the bounding boxes of the individual vectorial primitives by union, in which the more than one vectorial primitives include the following elementary vectorial primitives: - an elementary vectorial primitive describing a segment of straight line, possibly with thickness, and - an elementary vectorial primitive describing a cubic Bezier curve, possibly with thickness, Characterized in that: the calculation of the bounding box of the elementary vectorial primitive describing a cubic Bezier curve includes: - calculating the points of horizontal and vertical tangency to the Bezier curve: - if such points of horizontal and vertical tangency lie on the curve, taking the coordinates, in a reference system of coordinates, of such points of tangency as coordinates of the sides of the bounding box: while - if at least one of the points of horizontal and vertical tangency does not lie on the curve, taking as coordinates of the side of the bounding box the coordinates of the extreme point of the curve closer to the point of tangency that does not lie on the curve. calculating the bounding box for each vectorial primitive, and combining the bounding boxes of the individual vectorial primitives by union, in which the more than one vectorial primitives include the following elementary vectorial primitives: - an elementary vectorial primitive describing a segment of straight line, possibly with thickness, and - an elementary vectorial primitive describing a cubic Bezier curve, possibly with thickness, Characterized in that: the calculation of the bounding box of the elementary vectorial primitive describing a cubic Bezier curve includes: - calculating the points of horizontal and vertical tangency to the Bezier curve: - if such points of horizontal and vertical tangency lie on the curve, taking the coordinates, in a reference system of coordinates, of such points of tangency as coordinates of the sides of the bounding box: while - if at least one of the points of horizontal and vertical tangency does not lie on the curve, taking as coordinates of the side of the bounding box the coordinates of the extreme point of the curve closer to the point of tangency that does not lie on the curve. - an elementary vectorial primitive describing a segment of straight line, possibly with thickness, and - an elementary vectorial primitive describing a cubic Bezier curve, possibly with thickness, - calculating the points of horizontal and vertical tangency to the Bezier curve: - if such points of horizontal and vertical tangency lie on the curve, taking the coordinates, in a reference system of coordinates, of such points of tangency as coordinates of the sides of the bounding box: while - if at least one of the points of horizontal and vertical tangency does not lie on the curve, taking as coordinates of the side of the bounding box the coordinates of the extreme point of the curve closer to the point of tangency that does not lie on the curve.