Shape Healing

Shape Healing can be used to improve obtained shapes.


Shape Healing library provides algorithms to correct and adapt the geometry and topology of shapes imported to OCCT from other CAD systems.

Shape Healing algorithms include, but are not limited to, the following operations:

  • analyze shape characteristics and, in particular, identify the shapes that do not comply with OCCT geometry and topology validity rules by analyzing geometrical objects and topology:
    • check edge and wire consistency;
    • check edge order in a wire;
    • check the orientation of face boundaries;
    • analyze shape tolerances;
    • identify closed and open wires in a boundary.
  • fix incorrect or incomplete shapes:
    • provide consistency between a 3D curve and its corresponding parametric curve;
    • repair defective wires;
    • fit the shapes to a user-defined tolerance value;
    • fill gaps between patches and edges.
  • upgrade and change shape characteristics:
    • reduce curve and surface degree;
    • split shapes to obtain C1 continuity;
    • convert any types of curves or surfaces to Bezier or B-Spline curves or surfaces and back;
    • split closed surfaces and revolution surfaces.

Each sub-domain of Shape Healing has its own scope of functionality:

Sub-domain Description Impact on the shape
Analysis Explores shape properties, computes shape features, detects violation of OCCT requirements. The shape itself is not modified.
Fixing Fixes the shape to meet the OCCT requirements. The shape may change its original form: modification, removal or creation of sub-shapes, etc.)
Upgrade Improves the shape to fit some particular algorithms. The shape is replaced with a new one, but geometrically they are the same.
Customization Modifies the shape representation to fit specific needs. The shape is not modified, only the mathematical form of its internal representation is changed.
Processing Mechanism of shape modification via a user-editable resource file.  

For more details refer to Shape Healing User's guide.

See also: E-learning & Training.