gml:CubicSpline

The number of control points shall be at least three.
vectorAtStart is the unit tangent vector at the start point of the spline. vectorAtEnd is the unit tangent vector at the end point of the spline. Only the direction of the vectors shall be used to determine the shape of the cubic spline, not their length.
interpolation is fixed as "cubicSpline".
degree shall be the degree of the polynomial used for the interpolation in this spline. Therefore the degree for a cubic spline is fixed to "3".
The content model follows the general pattern for the encoding of curve segments.

Element information

Namespace: http://www.opengis.net/gml/3.2

Schema document: external/ogc/gml/3.2.1/geometryPrimitives.xsd

Type: gml:CubicSplineType

Properties: Global, Qualified

Content

Choice [1..1]
- Choice [2..*]
  - gml:pos
  - gml:pointPropertyThis property element either references a point via the XLink-attributes or contains the point element. pointProperty is the predefined property which may be used by GML Application Schemas whenever a GML feature has a property with a value that is substitutable for Point.
  - gml:pointRep
- gml:posList
- gml:coordinates
gml:vectorAtStart [1..1]
gml:vectorAtEnd [1..1]

Attributes

Name	Occ	Type	Notes
numDerivativesAtStart	[0..1]	xsd:integer	Default value is "0". from type gml:AbstractCurveSegmentType
numDerivativesAtEnd	[0..1]	xsd:integer	Default value is "0". from type gml:AbstractCurveSegmentType
numDerivativeInterior	[0..1]	xsd:integer	Default value is "0". from type gml:AbstractCurveSegmentType
interpolation	[0..1]	gml:CurveInterpolationType	Fixed value is "cubicSpline".
degree	[0..1]	xsd:integer	Fixed value is "3".

Used in

Type gml:ArrayAssociationType (Element gml:members)
Type gml:CurveSegmentArrayPropertyType (Element gml:segments)

Substitution hierarchy

gml:AbstractObject
- can be substituted with gml:AbstractCurveSegment
  - can be substituted with gml:CubicSpline

Sample instance

<gml:CubicSpline>
   <gml:pos>1.0 1.0</gml:pos>
   <gml:vectorAtStart>1.0 1.0</gml:vectorAtStart>
   <gml:vectorAtEnd>1.0 1.0</gml:vectorAtEnd>
</gml:CubicSpline>