Perimeterpin

Perimeterpin is a term used in some geometry, computer graphics, and design contexts to refer to an anchor or reference point located on the boundary (perimeter) of a shape. It is not a formal standard term, but rather an informal or domain-specific label for points that delineate or influence the shape’s boundary.

Definition and concept

A perimeterpin denotes a position on the boundary of a shape, often associated with a parameter or coordinate that identifies where along the perimeter the point lies. In practice, perimeterpins can serve as handles for deformation, sampling, or alignment, enabling operations that depend on the boundary rather than the interior.

Typical usage

- Boundary parameterization: perimeterpins mark specific parameter values along a boundary curve or polygon, facilitating operations like subdivision, offsetting, or morphing.

- Shape deformation: sets of perimeterpins can drive deformation by constraining boundary points while keeping interior structure coherent.

- Educational and visualization tools: pins on the perimeter help illustrate concepts such as circumference, arc length, or boundary curvature.

Representation and properties

In software, a perimeterpin is usually represented by a reference to a boundary entity (edge, curve, or polygon) and a parameter locating the point along that boundary. Depending on the system, the parameter may be a normalized distance along the boundary, an angular measure about a center, or a fractional position along a curve segment. Pins may also store orientation or a local tangent direction for downstream operations.

Relation to other concepts

Perimeterpins are related to anchor points, control points, and boundary representations. They are distinct from interior points and are often used in conjunction with boundary-centric algorithms in CAD, vector graphics, and geometric modeling.

Notes

Because perimeterpin is not a universally standardized term, its exact meaning can vary by application.