ArcClose2D

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ArcClose2D

ArcClose2D : X3DGeometryNode { 
  SFNode   [in,out] metadata    NULL  [X3DMetadataObject]
  SFString []       closureType "PIE" ["PIE"|"CHORD"]
  SFFloat  []       endAngle    π/2   [-2π,2π]
  SFFloat  []       radius      1     (0,∞)
  SFBool   []       solid       FALSE
  SFFloat  []       startAngle  0     [-2π,2π]
}

The ArcClose node specifies a portion of a circle whose center is at (0,0) and whose angles are measured starting at the positive x-axis and sweeping towards the positive y-axis. The end points of the arc specified are connected as defined by the closureType field. The radius field specifies the radius of the circle of which the arc is a portion. The arc extends from the startAngle counterclockwise to the endAngle. The value of radius shall be greater than zero. The values of startAngle and endAngle shall be in the range (0, 2π). If startAngle and endAngle have the same value, a circle is specified and closureType is ignored.

A closureType of "PIE" connects the end point to the start point by defining two straight line segments first from the end point to the center and then the center to the start point. This forms a pie wedge as shown in Figure 1. ArcClose2D node pie closure

http://www.web3d.org/x3d/specifications/ISO-IEC-19775-X3DAbstractSpecification/Images/ArcClose2DPie.gif
Figure 1 - ArcClose2D node ("PIE" closure) depiction

A closureType of "CHORD" connects the end point to the start point by defining a straight line segment from the end point to the start point. This forms an arc segment as shown in Figure 2. ArcClose2D node CHORD closure)

http://www.web3d.org/x3d/specifications/ISO-IEC-19775-X3DAbstractSpecification/Images/ArcClose2DChord.gif
Figure 2 - ArcClose2D node ("CHORD" closure) depiction

Textures are applied individually to each face of the ArcClose2D. On the front (+Z) and back (-Z) faces of the ArcClose2D, when viewed from the +Z-axis, the texture is mapped onto each face with the same orientation as if the image were displayed normally in 2D. TextureTransform affects the texture coordinates of the ArcClose2D (see 18.4.9 TextureTransform).