Type Method

newCylinderWithHeight:radii:radialSegments:verticalSegments:geometryType:inwardNormals:allocator:

Generates a mesh in the shape of a right circular or elliptical cylinder.

Declaration

+ (instancetype)newCylinderWithHeight:(float)height radii:(vector_float2)radii radialSegments:(NSUInteger)radialSegments verticalSegments:(NSUInteger)verticalSegments geometryType:(MDLGeometryType)geometryType inwardNormals:(BOOL)inwardNormals allocator:(id<MDLMeshBufferAllocator>)allocator;

Parameters

height

The height of the cylinder along the y-axis.

radii

The radii of the cylinder’s elliptical cross-section (in the x- and z-axis directions, respectively). If both radii are equal, this method generates a circular cylinder.

radialSegments

The number of points to generate around the horizontal circumference of the cylinder (that is, its cross-section in the xz-plane). A larger number of points increases rendering fidelity but decreases rendering performance.

verticalSegments

The number of points to generate along the height of the cylinder. A larger number of points increases rendering fidelity but decreases rendering performance.

geometryType

The type of geometric primitive from which to construct the mesh; must be MDLGeometryKindTriangles.

inwardNormals

YES to generate normal vectors pointing toward the central axis of the cylinder; NO to generate normal vectors pointing outward.

allocator

An object responsible for allocating mesh vertex data. If nil, Model I/O uses an internal allocator object.

Return Value

A new mesh object.

Discussion

This method generates vertex data for a cylinder centered at the origin of its local coordinate system.

The inwardNormals parameter determines the direction of generated vertex normal vectors for the mesh. Specify YES if the mesh will be viewed from inside (for example, for use in a sky effect), or NO if the mesh will be viewed from outside.

The allocator parameter controls vertex data allocation for the mesh. For example, to use the MetalKit framework for loading vertex data into GPU buffers for rendering using Metal, pass a MTKMeshBufferAllocator object. By specifying an allocator, you can ensure that mesh data is copied a minimal number of times between being read from a file and being loaded into GPU memory for rendering.

See Also

Creating Parametric Meshes