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.
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).
- 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.
- Default value true can completely hide geometry if viewed from wrong side!
ccw defines clockwise/counterclockwise ordering of vertex coordinates, which in turn defines front/back orientation of polygon normals according to Right-Hand Rule (RHR).
- 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.
- Consistent and correct ordering of left-handed or right-handed point sequences is important throughout the coord array of point values.
Defines cross-section of the surface traced about the trajectoryCurve axis.
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.
- Conceptually it is the NURBS equivalent of Extrusion but permits the use of non-closed cross sections.