Global Properties of Shapes

The Global Properties of Shapes component provides algorithms for computing the global properties of a composite geometric system in 3D space, and frameworks to query the computed results.

The global properties computed for a system are :

- its mass,

- its center of mass,

- its matrix of inertia,

- its moment about an axis,

- its radius of gyration about an axis,

- and its principal properties of inertia such as principal axis, principal moments, and principal radius of gyration.

Geometric systems are generally defined as shapes. Depending on the way they are analysed, these shapes will give properties of:

- lines induced from the edges of the shape,

- surfaces induced from the faces of the shape, or

- volumes induced from the solid bounded by the shape.

The global properties of several systems may be brought together to give the global properties of the system composed of the sum of all individual systems.

The Global Properties of Shapes component is composed of :

- seven functions for computing a shape's global properties: one function for lines, two functions for surfaces and four functions for volumes. The choice of functions depends on input parameters and algorithms used for computation (BRepGProp global functions),

- a framework for computing global properties for a set of points (GProp_PGProps),

- and a general framework to :

- bring together the global properties retained by several more elementary frameworks, and

- provide a general programming interface to consult computed global properties.