Add SwiftUI Example

li3zhen1 · Nov 5, 2023 · 1bafb99 · 1bafb99
1 parent 45e96e6
commit 1bafb99
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diff --git a/README.md b/README.md
@@ -8,7 +8,6 @@
   <img src="https://github.com/li3zhen1/Grape/actions/workflows/swift.yml/badge.svg" alt="swift workflow">
   <a href="https://swiftpackageindex.com/li3zhen1/Grape"><img src="https://img.shields.io/endpoint?url=https%3A%2F%2Fswiftpackageindex.com%2Fapi%2Fpackages%2Fli3zhen1%2FGrape%2Fbadge%3Ftype%3Dswift-versions" alt="swift package index"></a>
   <a href="https://swiftpackageindex.com/li3zhen1/Grape"><img src="https://img.shields.io/endpoint?url=https%3A%2F%2Fswiftpackageindex.com%2Fapi%2Fpackages%2Fli3zhen1%2FGrape%2Fbadge%3Ftype%3Dplatforms" alt="swift package index"></a>
-
 </p>
 
 <p align="center">A Swift library for force simulation and graph visualization.
@@ -83,7 +82,6 @@ struct ForceDirectedGraphSwiftUIExample: View {
             for i in 0..<2 {
                 LinkMark(from: i, to: i+1)
             }
-
         } forceField: {
             // Declare forces like you would do in D3.js.
             LinkForce()

diff --git a/Sources/ForceSimulation/Simulation2D/Simulation2D.CenterForce.swift b/Sources/ForceSimulation/Simulation2D/Simulation2D.CenterForce.swift
@@ -5,63 +5,62 @@
 //  Created by li3zhen1 on 10/16/23.
 //
 
-
 #if canImport(simd)
 
-import simd
+    import simd
 
-extension Simulation2D {
-    /// A force that drives nodes towards the center.
-    ///
-    /// Center force is relatively fast, the complexity is `O(n)`,
-    /// where `n` is the number of nodes.
-    /// See [Collide Force - D3](https://d3js.org/d3-force/collide).
-    final public class CenterForce: ForceLike
-    where NodeID: Hashable {
-        public typealias V = simd_double2
+    extension Simulation2D {
+        /// A force that drives nodes towards the center.
+        ///
+        /// Center force is relatively fast, the complexity is `O(n)`,
+        /// where `n` is the number of nodes.
+        /// See [Collide Force - D3](https://d3js.org/d3-force/collide).
+        final public class CenterForce: ForceLike
+        where NodeID: Hashable {
+            public typealias V = simd_double2
 
-        public var center: V
-        public var strength: V.Scalar
-        @usableFromInline weak var simulation: Simulation2D<NodeID>?
+            public var center: V
+            public var strength: V.Scalar
+            @usableFromInline weak var simulation: Simulation2D<NodeID>?
 
-        @inlinable internal init(center: V, strength: V.Scalar) {
-            self.center = center
-            self.strength = strength
-        }
+            @inlinable internal init(center: V, strength: V.Scalar) {
+                self.center = center
+                self.strength = strength
+            }
 
-        public func apply() {
-            guard let sim = self.simulation else { return }
-            // let alpha = sim.alpha
+            public func apply() {
+                guard let sim = self.simulation else { return }
+                // let alpha = sim.alpha
 
-            var meanPosition = V.zero
-            for n in sim.nodePositions {
-                meanPosition += n  //.position
-            }
-            let delta = meanPosition * (self.strength / V.Scalar(sim.nodePositions.count))
+                var meanPosition = V.zero
+                for n in sim.nodePositions {
+                    meanPosition += n  //.position
+                }
+                let delta = meanPosition * (self.strength / V.Scalar(sim.nodePositions.count))
 
-            for i in sim.nodePositions.indices {
-                sim.nodePositions[i] -= delta
+                for i in sim.nodePositions.indices {
+                    sim.nodePositions[i] -= delta
+                }
             }
+
         }
 
-    }
+        /// Create a center force that drives nodes towards the center.
+        ///
+        /// Center force is relatively fast, the complexity is `O(n)`,
+        /// where `n` is the number of nodes.
+        /// See [Collide Force - D3](https://d3js.org/d3-force/collide).
+        /// - Parameters:
+        ///  - center: The center of the force.
+        ///  - strength: The strength of the force.
+        @discardableResult
+        public func createCenterForce(center: V, strength: V.Scalar = 0.1) -> CenterForce {
+            let f = CenterForce(center: center, strength: strength)
+            f.simulation = self
+            self.forces.append(f)
+            return f
+        }
 
-    /// Create a center force that drives nodes towards the center.
-    /// 
-    /// Center force is relatively fast, the complexity is `O(n)`,
-    /// where `n` is the number of nodes.
-    /// See [Collide Force - D3](https://d3js.org/d3-force/collide).
-    /// - Parameters:
-    ///  - center: The center of the force.
-    ///  - strength: The strength of the force.
-    @discardableResult
-    public func createCenterForce(center: V, strength: V.Scalar = 0.1) -> CenterForce {
-        let f = CenterForce(center: center, strength: strength)
-        f.simulation = self
-        self.forces.append(f)
-        return f
     }
 
-}
-
 #endif