An icosphere creator written in Swift, with a SwiftUI SceneKit view that demos the generated geometries.
Ico generates the indices and vertices required to create an icosahedron or icosphere.
It returns the indices as [Int32] and the vertices as [SCNVector3] so the values can be plugged straight into SceneKit's geometry tools.
Ico's data could, however, be translated into other formats or modified to create stranger geometries.
The accompanying views use that data to render the shapes in a sample iOS app.
The Ico class creates an icosahedron, a polyhedron with 20 equilateral triangles.
It converts this into a sphere by splitting each triangle into four smaller triangles.
This process can be repeated to create progressively smoother spheres.
func generateIcoSphere(recursions: Int = 0) generateIcoSphere calculates the indices and vectors that define the icosphere geometry.
It has a default recursions value of 0, which will produce an unrefined icosahedron.
It returns its data in an Icosphere struct, in types that are compatible with SceneKit.
struct Icosphere {
let indices: [Int32]
let vertices: [SCNVector3]
}Ico was created as part of an iOS project and was designed to return data that could be modified before being used to create SceneKit geometries.
ScenekitView and ContentView render the data without any modification, other than allowing the level of recursion to be adjusted.
The views also add colours and allow toggling between solid/wireframe shapes to make the faces more visible.
These views run as an iOS app in XCode's content previews and simulators.
Fast Icosphere Mesh by Volodymyr Agafonkin https://observablehq.com/@mourner/fast-icosphere-mesh
Creating an icosphere mesh in code by Andreas Kahler http://blog.andreaskahler.com/2009/06/creating-icosphere-mesh-in-code.html
Gradient Meshes in SceneKit by MovingParts https://movingparts.io/gradient-meshes
Custom Geometry in SceneKit by Mike Lucking https://betterprogramming.pub/custom-geometry-in-scenekit-under-swiftui-35a95520e6d9