NurbsSweptSurface
Overview
NurbsSweptSurface uses a trajectoryCurve path to describe a generalized surface that is swept by a crossSectionCurve.
The NurbsSweptSurface node belongs to the NURBS component and requires at least level 3, its default container field is geometry. It is available from X3D version 3.0 or higher.
Hierarchy
1
2
3
4
+ X3DNode
+ X3DGeometryNode
+ X3DParametricGeometryNode
+ NurbsSweptSurface
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
SFBool [ ] solid TRUE
Setting solid true means draw only one side of polygons (backface culling on), setting solid false means draw both sides of polygons (backface culling off).
Hints
- Mnemonic “this geometry is solid like a brick” (you don’t render the inside of a brick).
- If in doubt, use solid=’false’ for maximum visibility.
- (X3D version 4.0 ISO.proof draft) accessType relaxed to inputOutput in order to support animation and visualization.
Warning
- Default value true can completely hide geometry if viewed from wrong side!
SFBool [ ] ccw TRUE
ccw defines clockwise/counterclockwise ordering of vertex coordinates, which in turn defines front/back orientation of polygon normals according to Right-Hand Rule (RHR).
Hints
- A good debugging technique for problematic polygons is to try changing the value of ccw, which can reverse solid effects (single-sided backface culling) and normal-vector direction.
- Clockwise
Warning
- Consistent and correct ordering of left-handed or right-handed point sequences is important throughout the coord array of point values.
SFNode [in, out] crossSectionCurve NULL [X3DNurbsControlCurveNode]
Defines cross-section of the surface traced about the trajectoryCurve axis.
SFNode [in, out] trajectoryCurve NULL [NurbsCurve]
Describes the center-line path using a NurbsCurve node, oriented so that it is defined counterclockwise when looking down the −Y axis, thus defining a concept of inside and outside.
Advice
Hint
- Conceptually it is the NURBS equivalent of Extrusion but permits the use of non-closed cross sections.