Concept definition

template<typename Shape>
concept geom::InteriorMeasurableObject =  DimensionalObject<Shape> and
    requires (const Shape& s)
{
    { s.measure_interior() } -> std::convertible_to<typename Shape::elem_t>;
}

Detailed Description

A shape which can measure its interior region.

For a 2D shape, this is the area; for a 3D shape, this is the volume; higher-dimensional shapes measure their hypervolumes.

These methods avoid the use of "area" and "volume" in their names to avoid confusion with the measure_boundary() method. ("Area" would measure the interior of a 2D shape, but the boundary of a 3D shape).