# newEllipsoid(withRadii:radialSegments:verticalSegments:geometryType:inwardNormals:hemisphere:allocator:) Creates a mesh in the shape of an ellipsoid or sphere. ``` class func newEllipsoid(withRadii radii: vector_float3, radialSegments: Int, verticalSegments: Int, geometryType: MDLGeometryType, inwardNormals: Bool, hemisphere: Bool, allocator: (any MDLMeshBufferAllocator)?) -> Self ``` ## Parameters `radii` A vector containing the width (x-component), height (y-component), and depth (z-component) of the bounding box of the ellipsoid to generate. If all components are equal, this method generates a sphere. `radialSegments` The number of points to generate around the horizontal circumference of the ellipsoid (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 ellipsoid. A larger number of points increases rendering fidelity but decreases rendering performance. `geometryType` The type of geometric primitive — triangles or quads — from which to construct the mesh. `inwardNormals` to generate normal vectors pointing toward the center of the ellipsoid; to generate normal vectors pointing outward. `hemisphere` to generate only the upper half of the ellipsoid or sphere (a dome); to generate a complete ellipsoid or sphere. `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 an ellipsoid centered at the origin of its local coordinate system. The `inwardNormals` parameter determines the direction of generated vertex normal vectors for the mesh. Specify if the mesh will be viewed from inside (for example, for use in a sky effect), or 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 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. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)