A sculpting brush is implemented by the BrushOperation class which derives directly from Node. A BrushOperation holds the properties of the brush tools like size, strength, direction, falloff, etc.

Falloffs (BrushOperation::FalloffData()) are arrays containing the points of a NURBS curves with degree 3. The falloff curve control points are set when the brush is created. Brushes can have stamps that modify the affected area.

The Mesh class has a number of functions for enumerating the faces starting from a given face using an enumerator object which decides whether to continue or halt enumeration in a given direction. This callback is used by the rest of the sculpt operation. The enumeration always starts from a selected (picked) point.