It is provided a computer-implemented method for designing a modeled volume. The method comprises providing a set of dexels (S10) that represents the modeled volume, each dexel comprising a set of at least one segment representing the intersection between a line and the modeled volume, wherein the set of dexels is partitioned into groups of neighboring dexels, and wherein a memory space depending on the maximum number of segments comprised in each of the dexels of the group is allocated to each group; providing a sculpting operation (S20) on the modeled volume; and updating (S30) the set of dexels in response to the sculpting operation. Such a method improves the design of a modeled volume represented by a set of dexels.