Geometric reasoning in sketch-based volumetric decomposition framework for hexahedral meshing

This paper presents a sketch-based volumetric decomposition framework using geometric reasoning to assist in hex meshing. The sketch-based user interface makes the framework user-friendly and intuitive, and the geometric reasoning engine makes the framework smarter and improves the usability. The system first generates a database that contains both the B-rep and 3D medial object to capture the exterior and interior of the input model, respectively. Next, the geometric reasoning process determines sweeping direction and two types of sweepable regions and provides visual aids to assist the user in developing decomposition solutions. The user conducts decomposition via the sketch-based user interface, which understands the user’s intent through freehand stroke inputs for smart decomposition. Imprint and merge operations are then performed on the decomposed model before passing it to the sweeping algorithm to create hex meshes. The proposed framework has been tested on industrial models.