Class

SCNTube

A tube or pipe geometry—a right circular cylinder with a circular hole along its central axis.

Declaration

@interface SCNTube : SCNGeometry

Overview

Figure 1

A tube and its properties

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.

Topics

Creating a Tube

+ tubeWithInnerRadius:outerRadius:height:

Creates a tube geometry with the specified inner radius, outer radius, and height.

Adjusting a Tube’s Dimensions

outerRadius

The radius of the tube’s outer circular cross section. Animatable.

innerRadius

The radius of the circular hole through the tube. Animatable.

height

The extent of the tube along its y-axis. Animatable.

Adjusting Geometric Detail

radialSegmentCount

The number of subdivisions around the circumference of the tube. Animatable.

heightSegmentCount

The number of subdivisions in the inner and outer surfaces of the tube along its y-axis. Animatable.

Relationships

Inherits From

See Also

Basic Shapes

SCNFloor

A plane that can optionally display a reflection of the scene above it.

SCNBox

A six-sided polyhedron geometry whose faces are all rectangles, optionally with rounded edges and corners.

SCNCapsule

A right circular cylinder geometry whose ends are capped with hemispheres.

SCNCone

A right circular cone or frustum geometry.

SCNCylinder

A right circular cylinder geometry.

SCNPlane

A rectangular, one-sided plane geometry of specified width and height.

SCNPyramid

A right rectangular pyramid geometry.

SCNSphere

A sphere (or ball or globe) geometry.

SCNTorus

A torus, or ring-shaped geometry.