Geometry 2D

The geometry classes were the easiest to write after I made the decision to build from the APIs my apps were using down to the macOS and Windows hosts. They were also the first I finished. The primitives herein pretty much align with what Taligent's Albert project had, though some of the names changed a bit. The simplest classes explicitly avoid virtual functions and avoid allocating memory. As such they do not require a virtual constructor and as a convenience they offer public members. The idea was those public members weren't going to change. Thirty three years later (as of August 2021) that idea still holds. All of the geometries are based on the special type Coord. It is used for all geometric members and parameters. Coord equates to the Guildhall scalar type fdual and that in turn to the 64-bit floating point type. Here are the geometry primitives.

Primitive	Description
TPoint	a 2D point with public members fX and fY
TRPoint	a 2D point with public members fX, fY, and the rational value fW
TLine	a 2D line with public TPoint members fStartPoint and fEndPoint
TRect	a 2D rectangle with public members fLeft, fTop, fRight, and fBottom
TEllipse	a 2D ellipse with a public TRect member fBounds
TRoundRect	a 2D rounded rectangle with a public TRect member fBounds and a public TPoint member fCurvature
TPointArray	an array of TPoint instances
TRPointArray	an array of TRPoint instances
TPolyline	a subclass of TPointArray that manages the polyline geometry
TPolygon	a subclass of TPolyline that adds the winding number boolean and closes the polyline to effect polygon geometry
TCurve	a subclass of TRPointArray that adds a knot vector and curve order to manage a NURB curve geometry
TShape	a subclass of TCurve that adds the winding number boolean and closes the curve to effect NURB shape geometry

The knot vector used in the TCurve class is a TCoordArray, discussed in the Arrays section.

Additonal Constructible Classes

TPath (experimental)
TRectArray (utility class)