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NurbsSet

Overview

NurbsSet collects a set of NurbsSurface nodes into a common group and treats NurbsSurface set as a unit during tessellation, thereby enforcing tessellation continuity along borders.

The NurbsSet node belongs to the NURBS component and requires at least level 2, its default container field is children. It is available from X3D version 3.0 or higher.

Hierarchy

1
2
3
+ X3DNode
  + X3DChildNode
    + NurbsSet (X3DBoundedObject)*

* Derived from multiple interfaces.

Fields

SFNode [in, out] metadata NULL [X3DMetadataObject]

Information about this node can be contained in a MetadataBoolean, MetadataDouble, MetadataFloat, MetadataInteger, MetadataString or MetadataSet node.

Hint

SFFloat [in, out] tessellationScale 1 (0,∞)

Scale for surface tessellation in children NurbsSurface nodes.

SFBool [in, out] visible TRUE

Whether or not renderable content within this node is visually displayed.

Hints

  • The visible field has no effect on animation behaviors, event passing or other non-visual characteristics.
  • Content must be visible to be collidable and to be pickable.

SFBool [in, out] bboxDisplay FALSE

Whether to display bounding box for associated geometry, aligned with world coordinates.

Hint

  • The bounding box is displayed regardless of whether contained content is visible.

SFVec3f [ ] bboxSize -1 -1 -1 [0,∞) or −1 −1 −1

Bounding box size is usually omitted, and can easily be calculated automatically by an X3D player at scene-loading time with minimal computational cost. Bounding box size can also be defined as an optional authoring hint that suggests an optimization or constraint.

Hints

SFVec3f [ ] bboxCenter 0 0 0 (-∞,∞)

Bounding box center accompanies bboxSize and provides an optional hint for bounding box position offset from origin of local coordinate system.

Hints

MFNode [in] addGeometry

Input field addGeometry.

MFNode [in] removeGeometry

Input field removeGeometry.

MFNode [in, out] geometry [ ] [X3DNurbsSurfaceGeometryNode]

The children form a closed loop with first point of first child repeated as last point of last child, and the last point of a segment repeated as first point of the consecutive one.

Hints

  • Children nodes are listed in consecutive order according to topology of the contour.
  • Utilizing USE nodes for geometry can ensure that rendered geometry occurs elsewhere in the model.

Warnings

  • geometry represented in children of this node shall not be directly rendered. It is an informational node only.
  • Surfaces not represented elsewhere in transformation hierarchy shall not be rendered.

Advice

Hint

  • USE nodes for geometry ensure renderable versions occur elsewhere in the model. The bounds information is provided for optimization purposes only. A browser may choose to use this information about when to apply trimming or smooth tessellation between patches based on the bounds information.

Warnings

  • Geometry represented in children of this node shall not be directly rendered. It is an informational node only.
  • Surfaces not represented elsewhere in transformation hierarchy shall not be rendered.

See Also

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