HitTestApp

SwiftUI & Scenekit hit testing example.

This example application is written for macOS, though with minor changes it should be able to be changed to an iOS app fairly quickly.

Many people have run into the issue that the SwiftUI SceneView doesn't appear to have any hit testing ability.
After much searching and working on this problem, I have discovered how to get the hit testing working. It involves using a small NSViewRepresentable (or UIViewRepresentable if on iOS) to get an SCNView which does conform to the SCNSceneRenderer protocol.

The ScenekitView class in this repo creates an SCNView for use by SwiftUI, replacing SceneView.

There are a number of other things in the contentView that are used as well. Such as using a DragGesture(minimumDistance: 0.0, coordinateSpace: .local).onEnded() in order to get the location of a tap, since a TapGesture() does not provide a location value, which is needed for feeding to the hitTest().

An example of using the DragGesture() to rotate the view is given.

I've also included a TapGesture() to double click on an object for centering the view on it. The camera system uses a camera node attached as the child of a camera orbit node in order to get the entire view to rotate around. the selected object.

Finally, there is a SwiftUI overlay on top of the Scene.

Comments

hit test is unreliable

first off, thank you for this example, it's incredible and well organized and documented! Would've taken forever to figure this out on my own.

One issue though, the raycasting doesn't seem to be reliable. Tried a bit of debugging and strangely, even if you're tapping on one of the circles, but you were previously rotating the camera, it doesn't always return any hits, resulting in no changing of the camera view.

Any ideas? Maybe it's due to some change in the latest xcode or something?

opened by edwonedwon 2