SCNTube
A tube or pipe geometry—a right circular cylinder with a circular hole along its central axis.
Declaration
class SCNTubeOverview
[Image]
The outer surface of a tube is a cylinder. Define the size of the cylinder’s cross section in the x- and z-axis dimensions of its local coordinate space with the outerRadius property, and its extent in the y-axis dimension with the height property. A cylinder becomes a tube through the subtraction of a cylindrical volume along its central axis. Define the size of this circular hole using the tube’s innerRadius property. To position and orient a tube in a scene, attach it to the geometry property of an SCNNode object.
Control the level of detail with the radialSegmentCount and heightSegmentCount properties. A higher radial segment count creates a smoother curve for the tube’s circular inner and outer surfaces. A higher segment count in either direction produces more vertices, which can improve rendering quality for certain lighting models or custom shader effects, but at a cost to rendering performance.
A tube contains four SCNGeometryElement objects: one each for its base and top, one that wraps around its outer surface, and one that wraps around its inner surface. SceneKit can render each element using a different material. For details, see the materials property in SCNGeometry.