Merge pull request #157 from DJBen/solar-touch

Update calculation method of solar systme scene tap handler
DJBen · Apr 5, 2018 · 37febef · 37febef
2 parents a40fe12 + f9dc6e1
commit 37febef
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Showing 3 changed files with 20 additions and 6 deletions.
diff --git a/Graviton/Common/Utils/SceneKit+Util.swift b/Graviton/Common/Utils/SceneKit+Util.swift
@@ -14,3 +14,13 @@ public let flipTextureContentsTransform: SCNMatrix4 = {
     mtx = SCNMatrix4Translate(mtx, 0.5, 0.5, 0)
     return mtx
 }()
+
+extension CGPoint {
+    init(_ vector: SCNVector3) {
+        self.init(x: CGFloat(vector.x), y: CGFloat(vector.y))
+    }
+
+    func distance(toPoint p: CGPoint) -> CGFloat {
+        return sqrt(pow(x - p.x, 2) + pow(y - p.y, 2))
+    }
+}
diff --git a/Graviton/SolarSystem/Scenes/SolarSystemScene.swift b/Graviton/SolarSystem/Scenes/SolarSystemScene.swift
@@ -30,7 +30,7 @@ class SolarSystemScene: SCNScene, CameraResponsive, FocusingSupport {
 
     private var orbitalMotions = [(OrbitalMotion, UIColor, Int)]()
     private var lineSegments = SCNNode()
-    private var spheres = SCNNode()
+    var spheres = SCNNode()
     var celestialBodies: [CelestialBody] = []
 
     var focusedNode: SCNNode?

diff --git a/Graviton/SolarSystem/ViewControllers/SolarSystemViewController.swift b/Graviton/SolarSystem/ViewControllers/SolarSystemViewController.swift
@@ -15,6 +15,8 @@ import MathUtil
 
 class SolarSystemViewController: SceneController {
 
+    static let focusDistanceThreshold: CGFloat = 30
+
     var focusController: FocusingSupport?
 
     var lastRenderTime: TimeInterval!
@@ -122,11 +124,13 @@ class SolarSystemViewController: SceneController {
 
     @objc func handleTap(sender: UITapGestureRecognizer) {
         let scnView = self.view as! SCNView
-        let p = sender.location(in: scnView)
-        let hitResults = scnView.hitTest(p, options: [.boundingBoxOnly: true])
-        let objectHit = hitResults.map { $0.node }.filter { $0.name != nil && $0.name!.contains("orbit") == false }
-        if objectHit.count > 0 {
-            let node = objectHit[0]
+        let point = sender.location(in: view)
+        let distances = solarSystemScene.spheres.childNodes.map { (sphere) -> (SCNNode, CGFloat) in
+            let screenPoint = CGPoint(scnView.projectPoint(sphere.position))
+            return (sphere, point.distance(toPoint: screenPoint))
+        }.sorted { $0.1 < $1.1 }.filter { $0.1 < SolarSystemViewController.focusDistanceThreshold }
+
+        if let (node, _) = distances.first {
             SCNTransaction.begin()
             SCNTransaction.animationDuration = 0.25
             focusController?.focus(atNode: node)