A geometric object shall be a combination of a coordinate geometry and a coordinate
reference system. In all of the operations, all geometric calculations shall be done in the coordinate
reference system of the first geometric object accessed, which is normally the object whose operation
is being invoked. Returned objects shall be in the coordinate reference system in which the calculations
are done unless explicitly stated otherwise. The interface defined in this package are basically those
of set theory. In general a geometric object is a set of geometric points, represented by
DirectPosition. Object instantiations of geometric objects are
Geometry. Object instantiations of geometric points, when used as values,
DirectPositions. General set theory operations defined at
Geometry differentiate further down the class hierarchy depending on
whether or not the boundary
DirectPosition are included as set
elements. Subtypes of
Primitive do not contain boundary points,
while subtypes of
Interface Summary Interface Description AffinePlacementA placement defined by linear transformation from the parameter space to the target coordinate space. ArcArc of the circle determined by 3 points, starting at the first, passing through the second and terminating at the third. ArcByBulgeEquivalents to the
Arc, except the bulge representation is maintained.
ArcStringSimilar to a line string except that the interpolation is by circular arcs. ArcStringByBulgeA variant of the arc that stores the parameters of the second constructor of the component arcs and recalculates the other attributes of the standard arc. BezierPolynomial splines that use Bezier or Bernstein polynomials for interpolation purposes. BicubicGridA gridded surface that uses cubic polynomial splines as the horizontal and vertical curves. BilinearGridA gridded surface that uses line strings as the horizontal and vertical curves. BSplineCurveA piecewise parametric polynomial or rational curve described in terms of control points and basis functions. BSplineSurfaceA rational or polynomial parametric surface that is represented by control points, basis functions and possibly weights. CircleSame as an arc, but closed to form a full circle. ClothoidThe clothoid (or Cornu's spiral), a plane curve whose curvature is a fixed function of its length. ConeA gridded surface given as a family of conic sections whose control points vary linearly. ConicAny general conic curve. CubicSplineCubic splines. CylinderA gridded surface given as a family of circles whose positions vary along a set of parallel lines, keeping the cross sectional horizontal curves of a constant shape. GenericCurveCommon interface for curve and curve segment. GenericSurfaceCommon interface for surface and surface patch. GeodesicTwo distinct positions joined by a geodesic curve. GeodesicStringSequence of geodesic segments. GeometryFactoryA factory of geometries. GriddedSurfaceA parametric curve surface defined from a rectangular grid in the parameter space. KnotControls the constructive parameter space for spline curves and surfaces. LineSegmentTwo distinct direct positions (the start point and end point) joined by a straight line. LineStringA sequence of line segments, each having a parameterization like the one
OffsetCurveA curve at a constant distance from the basis curve. ParametricCurveSurfaceThe surface patches that make up the parametric curve surfaces. ParamForPointThe curve parameter for a point. PlacementTakes a standard geometric construction and places it in geographic space. PointArrayA sequence of points. PointGridA grid of points. PolygonA surface patch that is defined by a set of boundary curves and an underlying surface to which these curves adhere. PolyhedralSurfaceA surface composed of polygon surfaces connected along their common boundary curves. PolynomialSplineA polynimal spline. PositionA type consisting of either a direct position or of a point from which a direct position shall be obtained. SphereA gridded surface given as a family of circles whose positions vary linearly along the axis of the sphere, and whose radius varies in proportion to the cosine function of the central angle. SplineCurveRoot for subtypes of curve segment using some version of spline, either polynomial or rational functions. TinA triangulated surface that uses the Delaunay algorithm or a similar algorithm complemented with consideration for breaklines, stoplines and maximum length of triangle sides. TriangleA planar polygon defined by 3 corners. TriangulatedSurfaceA polyhedral surface that is composed only of triangles.
Class Summary Class Description BSplineSurfaceFormIndicates a particular geometric form represented by a
KnotTypeThe type of a B-spline. SplineCurveFormIndicates which sort of curve may be approximated by a particular B-spline.