Added cone and cylinder geometries

Sources/RealityGeometries/CompleteVertex.swift

@@ -0,0 +1,38 @@
+//
+//  File.swift
+//  
+//
+//  Created by Max Cobb on 12/06/2021.
+//
+
+import RealityKit
+
+internal struct CompleteVertex {
+    var position: SIMD3<Float>
+    var normal: SIMD3<Float>
+    var uv: SIMD2<Float>
+}
+
+internal extension Array where Element == CompleteVertex {
+    func generateMeshDescriptor(
+        with indices: [UInt32], materials: [UInt32] = []
+    ) -> MeshDescriptor {
+        var meshDescriptor = MeshDescriptor()
+        var positions: [SIMD3<Float>] = []
+        var normals: [SIMD3<Float>] = []
+        var uvs: [SIMD2<Float>] = []
+        for vx in self {
+            positions.append(vx.position)
+            normals.append(vx.normal)
+            uvs.append(vx.uv)
+        }
+        meshDescriptor.positions = MeshBuffers.Positions(positions)
+        meshDescriptor.normals = MeshBuffers.Normals(normals)
+        meshDescriptor.textureCoordinates = MeshBuffers.TextureCoordinates(uvs)
+        meshDescriptor.primitives = .triangles(indices)
+        if !materials.isEmpty {
+            meshDescriptor.materials = MeshDescriptor.Materials.perFace(materials)
+        }
+        return meshDescriptor
+    }
+}

Sources/RealityGeometries/MeshResource+Cone.swift

@@ -0,0 +1,125 @@
+//
+//  File.swift
+//  
+//
+//  Created by Max Cobb on 12/06/2021.
+//
+
+import RealityKit
+
+extension MeshResource {
+    fileprivate static func coneIndices(_ sides: Int, _ lowerCenterIndex: UInt32, _ splitFaces: Bool) -> ([UInt32], [UInt32]) {
+        var indices: [UInt32] = []
+        var materialIndices: [UInt32] = []
+        for side in 0..<sides {
+            let bottomLeft = UInt32(side)
+            let bottomRight = UInt32(side + 1)
+            let topVertex = UInt32(side + sides + 1)
+
+            // First triangle of side
+            indices.append(contentsOf: [bottomLeft, topVertex, bottomRight])
+
+            // Add bottom cap triangle
+            indices.append(contentsOf: [0, UInt32(side) + 1, UInt32(side) + 2].map { $0 + lowerCenterIndex })
+
+            if splitFaces {
+                materialIndices.append(0)
+                materialIndices.append(1)
+            }
+        }
+        return (indices, materialIndices)
+    }
+
+    fileprivate static func coneVertices(
+        _ sides: Int, _ radius: Float, _ height: Float
+    ) -> ([CompleteVertex], [CompleteVertex], [CompleteVertex]) {
+        var theta: Float = 0
+        let thetaInc = 2 * .pi / Float(sides)
+        let uStep: Float = 1 / Float(sides);
+        // first vertices added will be bottom edges
+        var vertices = [CompleteVertex]()
+        // all top edge vertices of the cylinder
+        var upperEdgeVertices = [CompleteVertex]()
+        // bottom edge vertices
+        var lowerCapVertices = [CompleteVertex]()
+
+        // create vertices for all sides of the cylinder
+        for side in 0...sides {
+            let cosTheta = cos(theta)
+            let sinTheta = sin(theta)
+
+            let lowerPosition: SIMD3<Float> = [
+                radius * cosTheta, -height / 2, radius * sinTheta
+            ]
+
+            let lowerNormal = cross(
+                SIMD3<Float>(-sinTheta, 0, cosTheta),
+                SIMD3<Float>(0, 1, 0) - SIMD3<Float>(cosTheta, 0, sinTheta)
+            )
+            let bottomVertex = CompleteVertex(
+                position: lowerPosition,
+                normal: lowerNormal,
+                uv: [uStep * Float(side), 0]
+            )
+
+            // add vertex for bottom side of cylinder, facing out
+            vertices.append(bottomVertex)
+
+            // add vertex for bottom side facing down
+            lowerCapVertices.append(CompleteVertex(
+                position: bottomVertex.position,
+                normal: [0, -1, 0], uv: [cosTheta + 1, sinTheta + 1] / 2)
+            )
+
+            // add vertex for top side facing out
+            let topVertex = CompleteVertex(
+                position: [0, height / 2, 0],
+                normal: lowerNormal, uv: [0.5, 1]
+            )
+            upperEdgeVertices.append(topVertex)
+
+            theta += thetaInc;
+        }
+        return (vertices, upperEdgeVertices, lowerCapVertices)
+    }
+
+    /// Creates a new cone mesh with the specified values
+    /// - Parameters:
+    ///   - radius: Radius of the code base
+    ///   - height: Height of the code from base to tip
+    ///   - sides: How many sides the cone should have, default is 24, minimum is 3
+    ///   - splitFaces: A Boolean you set to true to indicate that vertices shouldn’t be merged.
+    /// - Returns: A cone mesh
+    public static func generateCone(
+        radius: Float, height: Float, sides: Int = 24, splitFaces: Bool = false
+    ) throws -> MeshResource {
+        assert(sides > 2, "Sides must be an integer above 2")
+        let halfHeight = height / 2
+
+        // first vertices added to vertices will be bottom edges
+        // upperEdgeVertices are all top edge vertices of the cylinder
+        // lowerCapVertices are the bottom edge vertices
+        var (
+            vertices, upperEdgeVertices, lowerCapVertices
+        ) = coneVertices(sides, radius, height)
+
+        vertices.append(contentsOf: upperEdgeVertices)
+
+        let lowerCenterIndex = UInt32(vertices.count)
+        vertices.append(CompleteVertex(
+            position: [0, -halfHeight, 0], normal: [0, -1, 0], uv: [0.5, 0.5]
+        ))
+
+        vertices.append(contentsOf: lowerCapVertices)
+
+        let (indices, materialIndices) = coneIndices(
+            sides, lowerCenterIndex, splitFaces
+        )
+
+        let meshDescr = vertices.generateMeshDescriptor(
+            with: indices, materials: materialIndices
+        )
+        return try MeshResource.generate(from: [meshDescr])
+    }
+}
+

Sources/RealityGeometries/MeshResource+Cylinder.swift

@@ -0,0 +1,143 @@
+//
+//  File.swift
+//  
+//
+//  Created by Max Cobb on 12/06/2021.
+//
+
+import RealityKit
+
+extension MeshResource {
+    fileprivate static func cylinderIndices(_ sides: Int, _ lowerCenterIndex: UInt32, _ upperCenterIndex: UInt32, _ splitFaces: Bool) -> ([UInt32], [UInt32]) {
+        var indices: [UInt32] = []
+        var materialIndices: [UInt32] = []
+        for side in 0..<sides {
+            let bottomLeft = UInt32(side)
+            let bottomRight = UInt32(side + 1)
+            let topLeft = UInt32(side + sides + 1)
+            let topRight = UInt32(side + sides + 2)
+
+            // First triangle of side
+            indices.append(contentsOf: [bottomLeft, topRight, bottomRight])
+
+            // Second triangle of side
+            indices.append(contentsOf: [bottomLeft, topLeft, topRight])
+
+            // Add bottom cap triangle
+            indices.append(contentsOf: [0, UInt32(side) + 1, UInt32(side) + 2].map { $0 + lowerCenterIndex })
+
+            // Add top cap triangle
+            indices.append(contentsOf: [0, UInt32(side) + 2, UInt32(side) + 1].map { $0 + upperCenterIndex })
+            if splitFaces {
+                materialIndices.append(0)
+                materialIndices.append(0)
+                materialIndices.append(1)
+                materialIndices.append(2)
+            }
+        }
+        return (indices, materialIndices)
+    }
+
+    fileprivate static func cylinderVertices(
+        _ sides: Int, _ radius: Float, _ height: Float
+    ) -> ([CompleteVertex], [CompleteVertex], [CompleteVertex], [CompleteVertex]) {
+        var theta: Float = 0
+        let normalizeMult = 1 / sqrt(radius)
+        let thetaInc = 2 * .pi / Float(sides)
+        let uStep: Float = 1 / Float(sides);
+        // first vertices added will be bottom edges
+        var vertices = [CompleteVertex]()
+        // all top edge vertices of the cylinder
+        var upperEdgeVertices = [CompleteVertex]()
+        // bottom edge vertices
+        var lowerCapVertices = [CompleteVertex]()
+        // top edge vertices
+        var upperCapVertices = [CompleteVertex]()
+
+        // create vertices for all sides of the cylinder
+        for side in 0...sides {
+            let cosTheta = cos(theta)
+            let sinTheta = sin(theta)
+
+            let lowerPosition: SIMD3<Float> = [
+                radius * cosTheta, -height / 2, radius * sinTheta
+            ]
+
+            let bottomVertex = CompleteVertex(
+                position: lowerPosition,
+                normal: [lowerPosition.x, 0, lowerPosition.z] * normalizeMult,
+                uv: [uStep * Float(side), 0]
+            )
+
+            // add vertex for bottom side of cylinder, facing out
+            vertices.append(bottomVertex)
+
+            // add vertex for bottom side facing down
+            lowerCapVertices.append(CompleteVertex(
+                position: bottomVertex.position,
+                normal: [0, -1, 0], uv: [cosTheta + 1, sinTheta + 1] / 2)
+            )
+
+            // add vertex for top side facing out
+            let topVertex = CompleteVertex(
+                position: bottomVertex.position + [0, height, 0],
+                normal: bottomVertex.normal, uv: [uStep * Float(side), 1]
+            )
+            upperEdgeVertices.append(topVertex)
+
+            upperCapVertices.append(CompleteVertex(
+                position: topVertex.position,
+                normal: [0, 1, 0], uv: [cosTheta + 1, sinTheta + 1] / 2)
+            )
+
+            theta += thetaInc;
+        }
+        return (vertices, upperEdgeVertices, lowerCapVertices, upperCapVertices)
+    }
+
+    /// Creates a new cylinder mesh with the specified values
+    /// - Parameters:
+    ///   - radius: Radius of the cylinder
+    ///   - height: Height of the cylinder
+    ///   - sides: How many sides the cone should have, default is 24, minimum is 3
+    ///   - splitFaces: A Boolean you set to true to indicate that vertices shouldn’t be merged.
+    /// - Returns: A cylinder mesh.
+    public static func generateCylinder(
+        radius: Float, height: Float, sides: Int = 24, splitFaces: Bool = false
+    ) throws -> MeshResource {
+        assert(sides > 2, "Sides must be an integer above 2")
+
+        let halfHeight = height / 2
+
+        // first vertices added to vertices will be bottom edges
+        // upperEdgeVertices are all top edge vertices of the cylinder
+        // lowerCapVertices are the bottom edge vertices
+        // upperCapVertices are the top edge vertices
+        var (
+            vertices, upperEdgeVertices, lowerCapVertices, upperCapVertices
+        ) = cylinderVertices(sides, radius, height)
+
+        vertices.append(contentsOf: upperEdgeVertices)
+
+        let lowerCenterIndex = UInt32(vertices.count)
+        vertices.append(CompleteVertex(
+            position: [0, -halfHeight, 0], normal: [0, -1, 0], uv: [0.5, 0.5]
+        ))
+
+        vertices.append(contentsOf: lowerCapVertices)
+        let upperCenterIndex = UInt32(vertices.count)
+        vertices.append(CompleteVertex(
+            position: [0, halfHeight, 0], normal: [0, 1, 0], uv: [0.5, 0.5]
+        ))
+        vertices.append(contentsOf: upperCapVertices)
+
+        let (indices, materialIndices) = cylinderIndices(
+            sides, lowerCenterIndex, upperCenterIndex, splitFaces
+        )
+
+        let meshDescr = vertices.generateMeshDescriptor(
+            with: indices, materials: materialIndices
+        )
+        return try MeshResource.generate(from: [meshDescr])
+    }
+}

Sources/RealityGeometries/MeshResource+Planes.swift

@@ -8,19 +8,29 @@
 import RealityKit
 
 extension MeshResource {
-    static func generateDetailedPlane(
+    /// Creates a new plane mesh with the specified values.
+    /// - Parameters:
+    ///   - width: Width of the output plane
+    ///   - depth: Depth of the output plane
+    ///   - vertices: Vertex count in the x and z axis
+    /// - Returns: A plane mesh
+    public static func generateDetailedPlane(
         width: Float, depth: Float, vertices: (Int, Int)
     ) throws -> MeshResource {
         var descr = MeshDescriptor()
         var meshPositions: [SIMD3<Float>] = []
         var indices: [UInt32] = []
-        for x_v in 0..<(vertices.0) { // 5
+        var textureMap: [SIMD2<Float>] = []
+        for x_v in 0..<(vertices.0) {
             let vertexCounts = meshPositions.count
             print(vertexCounts)
-            for y_v in 0..<(vertices.1) { // 4
+            for y_v in 0..<(vertices.1) {
                 meshPositions.append([
-                    (Float(x_v) / Float(vertices.0 - 1) - 0.5) * width, 0, (0.5 - Float(y_v) / Float(vertices.1 - 1)) * depth
+                    (Float(x_v) / Float(vertices.0 - 1) - 0.5) * width,
+                    0,
+                    (0.5 - Float(y_v) / Float(vertices.1 - 1)) * depth
                 ])
+                textureMap.append([Float(x_v) / Float(vertices.0 - 1), Float(y_v) / Float(vertices.1 - 1)])
                 if x_v > 0 && y_v > 0 {
                     indices.append(
                         contentsOf: [
@@ -32,8 +42,7 @@ extension MeshResource {
         }
         descr.primitives = .triangles(indices)
         descr.positions = MeshBuffer(meshPositions)
-        // - TODO: Add Texture Map
-//        descr.textureCoordinates = MeshBuffers.TextureCoordinates([])
+        descr.textureCoordinates = MeshBuffers.TextureCoordinates(textureMap)
         return try .generate(from: [descr])
     }
 }