xml-elliptical-arc

This is a non-composite and composite builder that constructs an elliptical arc geometry. The following elliptical arc definition is supported:

  1. An elliptical arc defined by a circle’s center, start and end point, primary-radius, secondary-radius, direction, rotation, and rotation-direction.

builder type: non-composite/composite, accepts point geometries in composite mode.

geometry constructed: arc geometry.

data parameters:

Data Name

Value

Required/
Optional

data-string

  1. The coordinate data string denotes the center, start and end point of an arc when the “direction” data parameter is present.

The coordinate data may be received as point geometries. These control points can be named or unnamed. The named point geometries can also be received in any order: their names must be one of “center”, “start” or “end”, or any of their equivalents (see below). If the point geometries are unnamed, then the order of the points is significant, the first point received is assumed as the center point, the next point as the start point, and the last point as the end point of the arc.

Equivalent control point names: The following names may be substituted for “center”, “start” and “end”:

  • center: CentrePoint
  • start: FromPoint
  • end: ToPoint

 

Range: String

Optional if the control points are to be passed in as point geometries; otherwise Required

primary-radius

The length of the primary axis for the ellipse the arc is based upon.

Range: A positive real number.

Default: There are no default values.

Required
secondary-radius

The length of the secondary axis for the ellipse the arc is based upon.

Range: A positive real number.

Default: There are no default values.

Required

direction

Specifies the traversal direction from the start to the end point the elliptical arc.

Range: cw | ccw

Default: There are no default values.

Required

rotation

The rotation of the ellipse that defines the arc. The rotation angle specifies the angle in degrees from the horizontal axis to the primary axis in the direction specified by the rotation-direction data parameter.

Range: A positive real number.

Default: 0.0

Optional

rotation-direction

Specifies the rotation direction. See the rotation data parameter.

Range: cw | ccw

Default: ccw

Required

axis-order

Indicates the axis for a coordinate.

Range: A permutation of the numbers 1..N, where N is the number of dimensions.

Each number is separated by a comma “,”.

Default: “1,2,...,N”

Optional, used only if data-string is specified

dimension

The dimension of the coordinates.

Range: String representing a positive integer, or the “implicit” literal, which forces the dimension to be automatically determined even if axis-order is specified.

Default: When not specified the dimension will be automatically determined.

Optional, used only if data-string is specified

axis-separator

The string separating each axis of a coordinate in the data-string.

Range: String | “whitespace” – this includes the tab, newline, and space characters.

Default: “,”

Optional, used only if data-string is specified

coord-separator

The string separating each coordinate in the data-string.

Range: String

Default: “whitespace” – this includes the tab, newline, and space characters.

Optional, used only if data-string is specified

decimal

The string representing the decimal point for each real number in the data-string.

Range: String

Default: “.”

Optional, used only if data-string is specified

coordinate-system

Specifies the coordinate system name. If the expression sequence for the coordinate-system evaluates to the empty string, then the coordinate system for the feature being built will not be set.

Range: String

Optional

demote-incomplete-geometry

This optional data parameter allows the xml-elliptical-arc geometry builder to return a non-geometrical object when no data-string is given or when the value of the data-string is the empty string.

Range: false | true

Default: false

Optional

incomplete-geometry-traits

This optional data parameter takes effect only when the demote-incomplete-geometry data parameter is set to true. This parameter lists the xml-elliptical-arc data parameters that should be loaded into the demoted arc geometry as traits. For example, when this geometry builder fails to construct an arc and demote-incomplete-geometry is set to true and the value for this parameter is set to “radius direction”, then the builder will construct a null geometry with radius and direction traits.

Range: whitespace separated list of arc data parameter names

Default: There are no default values.

Optional

name

Specifies the geometry’s name.

Range: String

Optional