I'm using ARKitSession and PlaneDetectionProvider to detect planes. I have a basics process to create an entity for each detected plane. Each one will get a random color for the material.
Each plane is sized based on the bounds of the anchor provided by ARKit.
let mesh = MeshResource.generatePlane(
width: anchor.geometry.extent.width,
depth: anchor.geometry.extent.height
)
Then I'm using this to position each entity.
entity.transform = Transform(matrix: anchor.originFromAnchorTransform)
This seems to be the right method, but many (not all) planes are not where they should be. The sizes look OK, but the X and Y positions off.
Take this large green plane on the wall. It should span the entire wall, but it is offset along the X position so that it is pushed to the left from where the center of the anchor is.
When I visualize surfaces using the Xcode debugging tools, that tool reports the planes where I'd expect them to be.
Can you see what I'm getting wrong here? Full code below
struct Example068: View {
@State var session = ARKitSession()
@State private var planeAnchors: [UUID: Entity] = [:]
@State private var planeColors: [UUID: Color] = [:]
var body: some View {
RealityView { content in
} update: { content in
for (_, entity) in planeAnchors {
if !content.entities.contains(entity) {
content.add(entity)
}
}
}
.task {
try! await setupAndRunPlaneDetection()
}
}
func setupAndRunPlaneDetection() async throws {
let planeData = PlaneDetectionProvider(alignments: [.horizontal, .vertical, .slanted])
if PlaneDetectionProvider.isSupported {
do {
try await session.run([planeData])
for await update in planeData.anchorUpdates {
switch update.event {
case .added, .updated:
let anchor = update.anchor
if planeColors[anchor.id] == nil {
planeColors[anchor.id] = generatePastelColor()
}
let planeEntity = createPlaneEntity(for: anchor, color: planeColors[anchor.id]!)
planeAnchors[anchor.id] = planeEntity
case .removed:
let anchor = update.anchor
planeAnchors.removeValue(forKey: anchor.id)
planeColors.removeValue(forKey: anchor.id)
}
}
} catch {
print("ARKit session error \(error)")
}
}
}
private func generatePastelColor() -> Color {
let hue = Double.random(in: 0...1)
let saturation = Double.random(in: 0.2...0.4)
let brightness = Double.random(in: 0.8...1.0)
return Color(hue: hue, saturation: saturation, brightness: brightness)
}
private func createPlaneEntity(for anchor: PlaneAnchor, color: Color) -> Entity {
let mesh = MeshResource.generatePlane(
width: anchor.geometry.extent.width,
depth: anchor.geometry.extent.height
)
var material = PhysicallyBasedMaterial()
material.baseColor.tint = UIColor(color)
let entity = ModelEntity(mesh: mesh, materials: [material])
entity.transform = Transform(matrix: anchor.originFromAnchorTransform)
return entity
}
}
